AC-201 Sound System
The AC-201 sound system was manufactured between July 1989 and January 1999. The following repair sheets are designed to help repair technicians and qualified owners repair and maintaining the AC-201.
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REMOVING THE AC-201 OR AC-205 AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws near each of the spring feet. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
AC-201 OR AC-205 TURNTABLE MOTOR REPLACEMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the chassis upside down on the padding with the controls toward you.
Note which wires go where and then unsolder the three leads, the two going to the motor and the one brown ground lead.
Locate the tension spring which provides the spring tension to hold the motor assembly up so that the drive wheel contacts the underside of the platter. Remove the two nuts and washer from this bolt, remove the spring and the motor assembly will swing out so that you can get at it. Remove one of the hex bolts holding the motor mount to the bracket, slide the rubber grommet off the other bolt and the motor assembly will come out.
Install the replacement motor by following above instructions in reverse order.
After reassembly you might have to readjust the spring tension and this can be done without disassembling the system. Lift off the platter and locate the slotted adjustment screw, about 1/4 inch from the rim of the drive wheel. Loosen the locknut, and turn the screw clockwise to decrease the spring tension, or counterclockwise to increase tension. Tighten the spring no more than necessary. When the tension is correct, tighten the locknut and replace the platter and the turntable is ready for use.
AC-201 OR AC-205 LIFTER REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The lifter electronics are contained on the printed circuit board located on the left side of the set. Check the cables to be sure they are in place. There are two plugs on the board, the 8 pin control /voltage and the lifter motor. Inspect these cables and note the orientation of the plugs.
BOARD REPLACEMENT
Remove the control / voltage cable from the lifter board. Unscrew the 4 screws on the left side of the chassis that secure the lifter board. Remove the lifter motor cable and slide the tie-downs off the spacers. CHECK THE LENGTH OF THE SPACERS. Two sizes were used in production. If they are different change them. Remount the board insuring the on/off switch is free to operate. Connect the control / voltage cable with the wires pointing to the front of the set.
SERVO REPLACEMENT
Turn the set right side up. Remove the two screws holding the lifter cover, and remove the cover. On the right side of the set there are two screws in slotted holes. Remove the screws and pull the servo upward. Put the new servo in place and get both screws started. Adjust the servo so that the top of the motor is 3/4" above the top deck and level. Replace the cover. Plug in the motor wire, black wire closest to the edge of the board. Use the tie-downs to hold the wire in place.
INSPECT THE PLUG PLACEMENT. BEING OFF BY ONE PIN WILL CAUSE PERMANENT DAMAGE. The motor plug should have the black wire closest to the topdeck for the set (bottom as viewed). The extra two pins on the connector should be in the middle of the board. The control / voltage plug should have the wires pointing to the front of the set and no pins showing on either side of the plug
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 OR AC-205 LIFTER REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The lifter electronics are contained on the printed circuit board located on the left side of the set. Check the cables to be sure they are in place. There are two plugs on the board, the 8 pin control /voltage and the lifter motor. Inspect these cables and note the orientation of the plugs. Check the plug that connects the control / voltage cable to the main board also.
BOARD REPLACEMENT
Remove the control / voltage cable from the lifter board. Unscrew the 4 screws on the left side of the chassis that secure the lifter board. Remove the motor cable and slide the tie-downs off the spacers. CHECK THE LENGTH OF THE SPACERS. Two sizes were used in production. If they are different change them.
Plug in the motor wire, black wire closest to the edge of the board. If you can slide the tie-downs on the spacers on the bottom of the board (away from the switch). Remount the board insuring the on/off switch is free to operate. Connect the control / voltage cable with the wires pointing to the front of the set.
INSPECT THE PLUG PLACEMENT. BEING OFF BY ONE PIN WILL CAUSE PERMANENT DAMAGE. The motor plug should have the black wire closest to the topdeck for the set (bottom as viewed). The extra two connectors on the board should be in the middle of the board. The control / voltage plug should have the wires pointing to the front of the set and no pins showing on either side of the plug.
ADJUSTMENTS
Turn the set right side up with the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 LIFTER ADJUSTMENT
Newer 201's have a plastic plug on the right side of the case. If your set has this plug, remove it and skip to "adjustments" as it does not have to be removed from the case.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off, manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj. (lower) so the needle is about 1/8" off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However, it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 DIAL READOUT LIFTER INSTALLATION
CHANGING ARMS
With a #0 phillips screwdriver (or a new #1) remove the black screw from the center of lifter arm cam. Turn the dial readout on the new arm so that the outer ring 0 is at the index line. Using an allen wrench remove the dial knob from the new arm. Turn the set and the lifter on to allow the motor to return to its rest position. Place the new arm on the motor as close to the horizontal as possible. Replace the black phillips screw. With the dial knob still off adjust the stop so the needle will come down in the lead-in section of the record. Replace the dial knob insuring that the little pin goes into the slot inside the center section.
Newer 201's have a plug in the right side of the case to provide access to the lifter adjustments. IF YOURS HAS THIS REMOVE THE PLUG AND SKIP TO TAKING THE SET OUT OF THE CASE.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading groove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
POWER ENTRANCE MODULE
The power entrance module contains the power off/on switch, fuse holder, voltage selector and power cord receptacle.
To open the power entrance module to replace the fuse or change voltage use a small screwdriver, ball point pen or similar device. Remove the power cord, insert tip of tool at a 45 degree angle into notch between the power cord receptacle and power module cover, apply pressure towards cover while prying upward.
To change the fuse, the fuse holder is attached to the cover and the fuse is easily removed and replaced. If the fuse again blows almost immediately, unplug the amplifier and do not attempt to use it until the cause of the problem has been determined. Refer to the trouble shooting section of this manual.
To change from 120 to 240 volts pull the voltage selector card straight out of the housing using the indicator pin. Orient the selector card so that the desired voltage is readable at the bottom of the card. Orient indicator pin to point up when desired voltage is readable at the bottom. Insert voltage selector card into the housing with edge showing selected voltage entering first and printed side of card facing the fuse compartment. Reinstall cover and verify the indicator pin shows the desired voltage.
If required the fused holder may be changed to take European standard fuses. Remove the Phillips head screw holding the fuse holder to the cover, turn the holder over and reinstall with the screw. The European arrangement requires two fuses..
CHANGING AN AC-201 OR AC-205 TURNTABLE FROM 60Hz TO 50Hz AC CURRENT OPERATION
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other soft material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of the case, lifting the front first so as to clear the jacks on the rear panel.
Turn the AC-201 chassis up side down, control panel away from you, on a pillow or soft foam to protect the tone arm. Locate the speed control transport, the throwout (which disengages the motor in the off position), and the microswitch that turns off the motor when the speed control is in the off position (see drawing). Loosen the 2 nuts holding the throwout and slide it all the way to the right, out of the way.
Set the unit on its side, so you can see and reach both the top and underside of the system. Move the speed control so that the knob is pointing at 54 R.P.M.. Note the position of the motor and speed control transport; this is the position you want the motor and speed control transport to be in when the knob is pointing at 45 R.P.M.
Holding the motor in place, loosen the 2 screws on the sped control transport and move the knob to 45 R.P.M. and then lightly retighten the 2 screws.
Now you can plug in the power cord, put on the platter, and check if the speed is set correctly. (A unit adjusted for 50HZ current will play a 45 RPM record at 37 1/2 on 60HZ current).If more adjusting is necessary be sure to unplug the power cord before readjusting the 2 screws on the speed control transport. Do this as many times as necessary to get the speed set correctly. Only when the speed is correct should you firmly tighten these 2 screws.
BE SURE THE SPEED IS ADJUSTED CORRECTLY BEFORE PROCEEDING!
Now that the speed is set correctly unplug the unit, move the knob to the off position, and turn it over again on the pillow or foam. Loosen the screw on the fiberglass plate (see drawing) and rotate the brown microswitch until there is about 1/16 inch of clearance between the leaf and the body of the switch. Retighten the screw.
Keep the speed control in the off position, and lift the motor so that you can slide the throwout back under the motor mount (metal piece) so it rests on the ledge shown in the drawing. This holds the drive wheel away from the platter in the off position. Retighten the nuts so that they are firm but not extremely tight. If you overtighten them the speed control will bind and not move freely.
Turn the unit right side up, plug in the power cord, and turn it on. Check to be sure that the turntable strobes correctly; that the motor turns off when the speed control knob is in the off position, that the speed control moves freely, and that the drive wheel disengages from the platter when the speed control knob is in the off position.
MOTOR NOISE AT 50HZ
Turntable motors that are adjusted to run properly at 60HZ often produce more noise when run at 50HZ. This extra noise is easily lowered by adding extra capacitors to the motor. The exact capacitance is often written on the motor itself from when we did the original checking of the motor. Either one or two .022 mfd. capacitors will bring the motor back to the original noise level. In most cases it will take both capacitors in parallel to make the motor run its most quiet. The capacitors are soldered onto the terminal strip as shown in the drawing.
Reinstall the chassis in the case and the job is finished.
AC-201 EQUALIZER JACK INSTALLATION
Installing an equalizer jack in your amplifier could reduce the resale value of your unit. Hilton Audio Products will not accept for trade-in a unit that has been so modified. You must be familiar with proper soldering technique and working with shielded cable.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material. Be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four black screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSTALLING EQUALIZER JACK
A 3/8" jack mounting hole must be drilled in the chassis between the phono treble control and mic 1 tone control. Carefully mark and drill the hole from the front. It must be in line with the center of the controls and in the black area of the label. Mount the jack with the hardware provided.
Turn the set upside down with the controls toward you. Locate the three shielded cables that are harnessed and go from the left side of the control panel to the main amplifier board. Two wires of the three are together. The third single one is the one we will work with. It connects to the P2 MUSIC control and runs along the front of the chassis with the other wires. Allowing some slack on both ends, cut the wire where it would cross the new jack.
Refer to the diagram below. Place a small jumper wire from (X) to ring of jack. Both shields will be connected to the ground lug (see diagram). The center wire of the shielded cable going to the MUSIC control connects to the ring, and the one going to the main board connects to the tip.
EQUALIZER JACK
(bottom view)
AC-201 CONNECTING BOTH MIC INPUTS TO TAPE OUT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Remove the 1 inch plastic reset access cover from the right side of the case. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the 201 on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
MODIFYING
5. Check the values of the following resistors and replace if needed.
R42, R36. R34 should be 33 K
R28 should be 39 K
6. Remove R38 and discard.
7. Tack one end of 100 K resistors to the intersection of:
R28 and R29 (pin 1 of Z2)
R34 and R33 (pin 7 of Z2)
R42 and R43 (pin 14 of Z2)
8. Connect the other end of all 3 resistors to the solder hole furthest from the edge of the board where R38 was connected (pin 10 of Z2)
REASSEMBLY
Place the 201 upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3 being carful to properly align the plug so all pins are connected. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
INSTALLING AC-201 TRANSFORMER HUM SHIELD
Remove the cover from the unit, lift out the platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws near each of the spring feet. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
Locate the power transformer mounted at the rear of the chassis. Remove the nuts from the two screws holding the top of the transformer laminates together. Place an "L" bracket over both screws pointing away from the center (see photo) and replace the nuts and tighten. Insure that the side with the threaded holes is level with the bottom of the set.
Re-route the Yellow and Red wires straight back to the back of the set, under the transformer windings if possible, to ensure clearance around the shield.
Place shield over the transformer, as shown in second photo, check that the wires are not pinched and secure with the two 6-32 x 1/4"screws.
Re assemble by placing the bottom of the case over the set, it may be necessary to press in on the front center of the chassis. Put the front two screws in the bottom first. If necessary to line up the back two screws turn the set so it is upright on the back panel where the power cord connects.
AC-201 4 VOLTAGE TRANSFORMER
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. MAKE CAREFUL NOTE OF HOW THE WIRES TO THE POWER MODULE AND TRANSFORMER ARE ROUTED. There are two slotted screws holding the left side of the main board in place. On the right hand side of the chassis, on the outside, there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT
1. Remove the two slotted screws on the outside right of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable at the center edge and the small plug next to it.
4. Unplug P6 from J6, the cable going to the transformer.
REPLACEMENT OF POWER MODULE/TRANSFORMER
1. Remove the hum shield from the transformer, held in place with two screws.
2. Remove the transformer being careful not to scratch the top deck when removing the 4 screws and nuts.
3. Remove the green chassis ground wire from under the nut and standoff.
4. Remove the power entry module.
5. Unsolder the small black wire from terminal F. and the small white wire from terminal D.
6. Cut the plastic ties to separate the wires in step 5 from the transformer wires. Set the old module and transformer aside.
INSTALL THE NEW MODULE/TRANSFORMER
1. Solder the black wire to terminal F of the new module and the white wire to terminal D.
2. Install the power entry module, insuring the switch is toward the transformer location. Route the wires to the transformer under the power module.
3. Install the green ground wire under the nut and standoff.
4. Install the transformer being sure the wires from the power module run between the transformer and the back of the set.
5. Reinstall the transformer hum shield.
REASSEMBLY
1. Plug in J6 and swing the circuit board into place temporally. Route the wires from the transformer to J6 along the top of the power module.
2. Reconnect the other two cables, BE SURE THE MULTI COLORED CABLE IS IN PLACE CORRECTLY, PERMANENT DAMAGE WILL RESULT IF IT IS ONE PIN OFF EITHER WAY.
3. Replace the 4 screws holding the circuit board in place, two in the board and 2 on the right side of the chassis.
4. SET THE POWER SELECTOR TO PROPER VOLTAGE.
5. Check the unit for proper operation.
6. Put the set in the case and secure with 4 screws.
INSTALLING A 4 VOLTAGE TRANSFORMER IN OLDER 201'S
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. MAKE CAREFUL NOTE OF HOW THE WIRES TO THE AC POWER INPUT MODULE (CORCOM) AND TRANSFORMER ARE ROUTED. There are two slotted screws holding the left side of the main board in place. On the right hand side of the chassis, on the outside, there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT
1. Remove the two slotted screws on the outside right of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable at the center edge and the small plug next to it.
4. Unplug P6 from J6, the cable going to the transformer.
REMOVAL OF THE TRANSFORMER
1. Remove the hum shield from the transformer, held in place with two screws.
2. Identify the 2 wires going to the motor and switch assembly and check the color of the wire going to the switch (probably white or red) and the one going to the motor (probably black or yellow) . Mark the schematic with the appropriate color. And remove them. From the power input module (Corcom)
3. Identify the two wires going to the strobe bulb. And remove them.
4. Unsolder the transformer wires.
5. Remove the transformer being careful not to scratch the top deck when removing the 4 screws and nuts.
6. Remove the jumper from terminal L to J
INSTALL THE NEW TRANSFORMER
1. Verify that the two wires coming from the (motor / strobe / switch assembly) are connected to either F & D or (C & E as on the schematic).
2. Reconnect all wires to the Corcom AC power input module as shown on the schematic
3. Install the transformer being sure the wires from the power module run between the transformer and the back of the set.
4. Reinstall the transformer hum shield.
REASSEMBLY
1. Plug in J6 and swing the circuit board into place temporally. Route the wires from the transformer to J6 along the top of the power module.
2. Reconnect the other two cables, BE SURE THE MULTI COLORED CABLE IS IN PLACE CORRECTLY, PERMANENT DAMAGE WILL RESULT IF IT IS ONE PIN OFF EITHER WAY.
3. Replace the 4 screws holding the circuit board in place, two in the board and 2 on the right side of the chassis.
4. SET THE POWER SELECTOR TO PROPER VOLTAGE. Insert the new power selector chip.
5. Check for proper fuse, 3A for 100-12v and two 1.6A for 220-240V. See the instruction manual.
6. Check the unit for proper operation.
7. Put the set in the case and secure with 4 screws.
AC-201 OR AC-205 I.C. REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the 201 on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
REPLACING THE I.C.
The 8 pin remote volume chip (829 or SK3891) is on the main board near the flat ribbon connector. Note the index marking on the package drawing and on the I.C. in the set. Remove the old I.C. and replace it insuring that the index is closest to the ribbon connector. Inspect to insure all pins are properly in place.
REASSEMBLY
Place the unit upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
AC-201 OR AC-205 MIC. DIODE REPLACEMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connect to the board and are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the unit on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
REPLACING MIC DIODES
The microphone input diodes are designed to limit the input signal to normal levels, less than 1v. If a strong signal, ie. line or speaker level signal is put into the mic jacks the diodes may short in order to save the rest of the circuit resulting in a "dead mic channel."
The 8 diodes are located near the mic input jack J2. D1 - D4 are for mic 1 and D5 - D8 are mic 2's. Remove and replace the diodes using vacuum or solder-wick techniques. If you have not worked on 2 sided plated-through pc boards you can cut the leads and tack the new diode on the old leads.
REASSEMBLY
Place the unit upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3. INSPECT THE PLUGS AND INSURE THAT THERE ARE NO PINS LEFT VISIBLE. FAILURE TO PROPERLY ALIGN THE PLUG WILL RESULT IN PERMANENT DAMAGE TO THE LIFTER CIRCUITS. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
Remove the cover from the unit, lift out the platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws near each of the spring feet. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
AC-201 OR AC-205 TURNTABLE MOTOR REPLACEMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the chassis upside down on the padding with the controls toward you.
Note which wires go where and then unsolder the three leads, the two going to the motor and the one brown ground lead.
Locate the tension spring which provides the spring tension to hold the motor assembly up so that the drive wheel contacts the underside of the platter. Remove the two nuts and washer from this bolt, remove the spring and the motor assembly will swing out so that you can get at it. Remove one of the hex bolts holding the motor mount to the bracket, slide the rubber grommet off the other bolt and the motor assembly will come out.
Install the replacement motor by following above instructions in reverse order.
After reassembly you might have to readjust the spring tension and this can be done without disassembling the system. Lift off the platter and locate the slotted adjustment screw, about 1/4 inch from the rim of the drive wheel. Loosen the locknut, and turn the screw clockwise to decrease the spring tension, or counterclockwise to increase tension. Tighten the spring no more than necessary. When the tension is correct, tighten the locknut and replace the platter and the turntable is ready for use.
AC-201 OR AC-205 LIFTER REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The lifter electronics are contained on the printed circuit board located on the left side of the set. Check the cables to be sure they are in place. There are two plugs on the board, the 8 pin control /voltage and the lifter motor. Inspect these cables and note the orientation of the plugs.
BOARD REPLACEMENT
Remove the control / voltage cable from the lifter board. Unscrew the 4 screws on the left side of the chassis that secure the lifter board. Remove the lifter motor cable and slide the tie-downs off the spacers. CHECK THE LENGTH OF THE SPACERS. Two sizes were used in production. If they are different change them. Remount the board insuring the on/off switch is free to operate. Connect the control / voltage cable with the wires pointing to the front of the set.
SERVO REPLACEMENT
Turn the set right side up. Remove the two screws holding the lifter cover, and remove the cover. On the right side of the set there are two screws in slotted holes. Remove the screws and pull the servo upward. Put the new servo in place and get both screws started. Adjust the servo so that the top of the motor is 3/4" above the top deck and level. Replace the cover. Plug in the motor wire, black wire closest to the edge of the board. Use the tie-downs to hold the wire in place.
INSPECT THE PLUG PLACEMENT. BEING OFF BY ONE PIN WILL CAUSE PERMANENT DAMAGE. The motor plug should have the black wire closest to the topdeck for the set (bottom as viewed). The extra two pins on the connector should be in the middle of the board. The control / voltage plug should have the wires pointing to the front of the set and no pins showing on either side of the plug
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 OR AC-205 LIFTER REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The lifter electronics are contained on the printed circuit board located on the left side of the set. Check the cables to be sure they are in place. There are two plugs on the board, the 8 pin control /voltage and the lifter motor. Inspect these cables and note the orientation of the plugs. Check the plug that connects the control / voltage cable to the main board also.
BOARD REPLACEMENT
Remove the control / voltage cable from the lifter board. Unscrew the 4 screws on the left side of the chassis that secure the lifter board. Remove the motor cable and slide the tie-downs off the spacers. CHECK THE LENGTH OF THE SPACERS. Two sizes were used in production. If they are different change them.
Plug in the motor wire, black wire closest to the edge of the board. If you can slide the tie-downs on the spacers on the bottom of the board (away from the switch). Remount the board insuring the on/off switch is free to operate. Connect the control / voltage cable with the wires pointing to the front of the set.
INSPECT THE PLUG PLACEMENT. BEING OFF BY ONE PIN WILL CAUSE PERMANENT DAMAGE. The motor plug should have the black wire closest to the topdeck for the set (bottom as viewed). The extra two connectors on the board should be in the middle of the board. The control / voltage plug should have the wires pointing to the front of the set and no pins showing on either side of the plug.
ADJUSTMENTS
Turn the set right side up with the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 LIFTER ADJUSTMENT
Newer 201's have a plastic plug on the right side of the case. If your set has this plug, remove it and skip to "adjustments" as it does not have to be removed from the case.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading grove of a record. With the power off, manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj. (lower) so the needle is about 1/8" off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However, it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
AC-201 DIAL READOUT LIFTER INSTALLATION
CHANGING ARMS
With a #0 phillips screwdriver (or a new #1) remove the black screw from the center of lifter arm cam. Turn the dial readout on the new arm so that the outer ring 0 is at the index line. Using an allen wrench remove the dial knob from the new arm. Turn the set and the lifter on to allow the motor to return to its rest position. Place the new arm on the motor as close to the horizontal as possible. Replace the black phillips screw. With the dial knob still off adjust the stop so the needle will come down in the lead-in section of the record. Replace the dial knob insuring that the little pin goes into the slot inside the center section.
Newer 201's have a plug in the right side of the case to provide access to the lifter adjustments. IF YOURS HAS THIS REMOVE THE PLUG AND SKIP TO TAKING THE SET OUT OF THE CASE.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
ADJUSTMENTS
Adjustments are made with the set right side up and the platter in place. On the right side of the set there is a 1 inch square opening with access to three screwdriver adjustments. The top left sets the low or rest point. The bottom center sets the high or up point. The top right is a factory set adjustment of the cycle speed, this should be the last adjustment made and then only if needed.
Set the lifter arm stop point so that the arm would drop in the leading groove of a record. With the power off manually move the reset arm to find the proper setting.
Place the tone arm on its rest and turn the set and the lifter on. Adjust the low (top left) so that the lifter arm is just above the top deck. Press and hold the reset button and adjust the high adj (lower) so the needle is about 1/8 inch off the record. Release the reset button and reset the low point. The low and high adjustments interact slightly and you must work back and forth a couple of times.
REFINING THE ADJUSTMENTS
Most callers never reset to the start of the record. You may place the stop to the point you are going to use for your records and reset the high point. This will result in a lower setting off the record and a softer needle drop. However it will have to be reset if the stop is moved.
If necessary the speed may be adjusted to your desires. If the tone-arm bounces when lifted from the center of the record, the speed is TOO FAST. If the high point is correct and the needle slides across the record the speed is TOO SLOW.
POWER ENTRANCE MODULE
The power entrance module contains the power off/on switch, fuse holder, voltage selector and power cord receptacle.
To open the power entrance module to replace the fuse or change voltage use a small screwdriver, ball point pen or similar device. Remove the power cord, insert tip of tool at a 45 degree angle into notch between the power cord receptacle and power module cover, apply pressure towards cover while prying upward.
To change the fuse, the fuse holder is attached to the cover and the fuse is easily removed and replaced. If the fuse again blows almost immediately, unplug the amplifier and do not attempt to use it until the cause of the problem has been determined. Refer to the trouble shooting section of this manual.
To change from 120 to 240 volts pull the voltage selector card straight out of the housing using the indicator pin. Orient the selector card so that the desired voltage is readable at the bottom of the card. Orient indicator pin to point up when desired voltage is readable at the bottom. Insert voltage selector card into the housing with edge showing selected voltage entering first and printed side of card facing the fuse compartment. Reinstall cover and verify the indicator pin shows the desired voltage.
If required the fused holder may be changed to take European standard fuses. Remove the Phillips head screw holding the fuse holder to the cover, turn the holder over and reinstall with the screw. The European arrangement requires two fuses..
CHANGING AN AC-201 OR AC-205 TURNTABLE FROM 60Hz TO 50Hz AC CURRENT OPERATION
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other soft material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of the case, lifting the front first so as to clear the jacks on the rear panel.
Turn the AC-201 chassis up side down, control panel away from you, on a pillow or soft foam to protect the tone arm. Locate the speed control transport, the throwout (which disengages the motor in the off position), and the microswitch that turns off the motor when the speed control is in the off position (see drawing). Loosen the 2 nuts holding the throwout and slide it all the way to the right, out of the way.
Set the unit on its side, so you can see and reach both the top and underside of the system. Move the speed control so that the knob is pointing at 54 R.P.M.. Note the position of the motor and speed control transport; this is the position you want the motor and speed control transport to be in when the knob is pointing at 45 R.P.M.
Holding the motor in place, loosen the 2 screws on the sped control transport and move the knob to 45 R.P.M. and then lightly retighten the 2 screws.
Now you can plug in the power cord, put on the platter, and check if the speed is set correctly. (A unit adjusted for 50HZ current will play a 45 RPM record at 37 1/2 on 60HZ current).If more adjusting is necessary be sure to unplug the power cord before readjusting the 2 screws on the speed control transport. Do this as many times as necessary to get the speed set correctly. Only when the speed is correct should you firmly tighten these 2 screws.
BE SURE THE SPEED IS ADJUSTED CORRECTLY BEFORE PROCEEDING!
Now that the speed is set correctly unplug the unit, move the knob to the off position, and turn it over again on the pillow or foam. Loosen the screw on the fiberglass plate (see drawing) and rotate the brown microswitch until there is about 1/16 inch of clearance between the leaf and the body of the switch. Retighten the screw.
Keep the speed control in the off position, and lift the motor so that you can slide the throwout back under the motor mount (metal piece) so it rests on the ledge shown in the drawing. This holds the drive wheel away from the platter in the off position. Retighten the nuts so that they are firm but not extremely tight. If you overtighten them the speed control will bind and not move freely.
Turn the unit right side up, plug in the power cord, and turn it on. Check to be sure that the turntable strobes correctly; that the motor turns off when the speed control knob is in the off position, that the speed control moves freely, and that the drive wheel disengages from the platter when the speed control knob is in the off position.
MOTOR NOISE AT 50HZ
Turntable motors that are adjusted to run properly at 60HZ often produce more noise when run at 50HZ. This extra noise is easily lowered by adding extra capacitors to the motor. The exact capacitance is often written on the motor itself from when we did the original checking of the motor. Either one or two .022 mfd. capacitors will bring the motor back to the original noise level. In most cases it will take both capacitors in parallel to make the motor run its most quiet. The capacitors are soldered onto the terminal strip as shown in the drawing.
Reinstall the chassis in the case and the job is finished.
AC-201 EQUALIZER JACK INSTALLATION
Installing an equalizer jack in your amplifier could reduce the resale value of your unit. Hilton Audio Products will not accept for trade-in a unit that has been so modified. You must be familiar with proper soldering technique and working with shielded cable.
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material. Be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four black screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSTALLING EQUALIZER JACK
A 3/8" jack mounting hole must be drilled in the chassis between the phono treble control and mic 1 tone control. Carefully mark and drill the hole from the front. It must be in line with the center of the controls and in the black area of the label. Mount the jack with the hardware provided.
Turn the set upside down with the controls toward you. Locate the three shielded cables that are harnessed and go from the left side of the control panel to the main amplifier board. Two wires of the three are together. The third single one is the one we will work with. It connects to the P2 MUSIC control and runs along the front of the chassis with the other wires. Allowing some slack on both ends, cut the wire where it would cross the new jack.
Refer to the diagram below. Place a small jumper wire from (X) to ring of jack. Both shields will be connected to the ground lug (see diagram). The center wire of the shielded cable going to the MUSIC control connects to the ring, and the one going to the main board connects to the tip.
EQUALIZER JACK
(bottom view)
AC-201 CONNECTING BOTH MIC INPUTS TO TAPE OUT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Remove the 1 inch plastic reset access cover from the right side of the case. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the 201 on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
MODIFYING
5. Check the values of the following resistors and replace if needed.
R42, R36. R34 should be 33 K
R28 should be 39 K
6. Remove R38 and discard.
7. Tack one end of 100 K resistors to the intersection of:
R28 and R29 (pin 1 of Z2)
R34 and R33 (pin 7 of Z2)
R42 and R43 (pin 14 of Z2)
8. Connect the other end of all 3 resistors to the solder hole furthest from the edge of the board where R38 was connected (pin 10 of Z2)
REASSEMBLY
Place the 201 upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3 being carful to properly align the plug so all pins are connected. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
INSTALLING AC-201 TRANSFORMER HUM SHIELD
Remove the cover from the unit, lift out the platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws near each of the spring feet. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
Locate the power transformer mounted at the rear of the chassis. Remove the nuts from the two screws holding the top of the transformer laminates together. Place an "L" bracket over both screws pointing away from the center (see photo) and replace the nuts and tighten. Insure that the side with the threaded holes is level with the bottom of the set.
Re-route the Yellow and Red wires straight back to the back of the set, under the transformer windings if possible, to ensure clearance around the shield.
Place shield over the transformer, as shown in second photo, check that the wires are not pinched and secure with the two 6-32 x 1/4"screws.
Re assemble by placing the bottom of the case over the set, it may be necessary to press in on the front center of the chassis. Put the front two screws in the bottom first. If necessary to line up the back two screws turn the set so it is upright on the back panel where the power cord connects.
AC-201 4 VOLTAGE TRANSFORMER
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. MAKE CAREFUL NOTE OF HOW THE WIRES TO THE POWER MODULE AND TRANSFORMER ARE ROUTED. There are two slotted screws holding the left side of the main board in place. On the right hand side of the chassis, on the outside, there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT
1. Remove the two slotted screws on the outside right of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable at the center edge and the small plug next to it.
4. Unplug P6 from J6, the cable going to the transformer.
REPLACEMENT OF POWER MODULE/TRANSFORMER
1. Remove the hum shield from the transformer, held in place with two screws.
2. Remove the transformer being careful not to scratch the top deck when removing the 4 screws and nuts.
3. Remove the green chassis ground wire from under the nut and standoff.
4. Remove the power entry module.
5. Unsolder the small black wire from terminal F. and the small white wire from terminal D.
6. Cut the plastic ties to separate the wires in step 5 from the transformer wires. Set the old module and transformer aside.
INSTALL THE NEW MODULE/TRANSFORMER
1. Solder the black wire to terminal F of the new module and the white wire to terminal D.
2. Install the power entry module, insuring the switch is toward the transformer location. Route the wires to the transformer under the power module.
3. Install the green ground wire under the nut and standoff.
4. Install the transformer being sure the wires from the power module run between the transformer and the back of the set.
5. Reinstall the transformer hum shield.
REASSEMBLY
1. Plug in J6 and swing the circuit board into place temporally. Route the wires from the transformer to J6 along the top of the power module.
2. Reconnect the other two cables, BE SURE THE MULTI COLORED CABLE IS IN PLACE CORRECTLY, PERMANENT DAMAGE WILL RESULT IF IT IS ONE PIN OFF EITHER WAY.
3. Replace the 4 screws holding the circuit board in place, two in the board and 2 on the right side of the chassis.
4. SET THE POWER SELECTOR TO PROPER VOLTAGE.
5. Check the unit for proper operation.
6. Put the set in the case and secure with 4 screws.
INSTALLING A 4 VOLTAGE TRANSFORMER IN OLDER 201'S
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. MAKE CAREFUL NOTE OF HOW THE WIRES TO THE AC POWER INPUT MODULE (CORCOM) AND TRANSFORMER ARE ROUTED. There are two slotted screws holding the left side of the main board in place. On the right hand side of the chassis, on the outside, there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT
1. Remove the two slotted screws on the outside right of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable at the center edge and the small plug next to it.
4. Unplug P6 from J6, the cable going to the transformer.
REMOVAL OF THE TRANSFORMER
1. Remove the hum shield from the transformer, held in place with two screws.
2. Identify the 2 wires going to the motor and switch assembly and check the color of the wire going to the switch (probably white or red) and the one going to the motor (probably black or yellow) . Mark the schematic with the appropriate color. And remove them. From the power input module (Corcom)
3. Identify the two wires going to the strobe bulb. And remove them.
4. Unsolder the transformer wires.
5. Remove the transformer being careful not to scratch the top deck when removing the 4 screws and nuts.
6. Remove the jumper from terminal L to J
INSTALL THE NEW TRANSFORMER
1. Verify that the two wires coming from the (motor / strobe / switch assembly) are connected to either F & D or (C & E as on the schematic).
2. Reconnect all wires to the Corcom AC power input module as shown on the schematic
3. Install the transformer being sure the wires from the power module run between the transformer and the back of the set.
4. Reinstall the transformer hum shield.
REASSEMBLY
1. Plug in J6 and swing the circuit board into place temporally. Route the wires from the transformer to J6 along the top of the power module.
2. Reconnect the other two cables, BE SURE THE MULTI COLORED CABLE IS IN PLACE CORRECTLY, PERMANENT DAMAGE WILL RESULT IF IT IS ONE PIN OFF EITHER WAY.
3. Replace the 4 screws holding the circuit board in place, two in the board and 2 on the right side of the chassis.
4. SET THE POWER SELECTOR TO PROPER VOLTAGE. Insert the new power selector chip.
5. Check for proper fuse, 3A for 100-12v and two 1.6A for 220-240V. See the instruction manual.
6. Check the unit for proper operation.
7. Put the set in the case and secure with 4 screws.
AC-201 OR AC-205 I.C. REPLACEMENT AND ADJUSTMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connected to the board are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the 201 on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
REPLACING THE I.C.
The 8 pin remote volume chip (829 or SK3891) is on the main board near the flat ribbon connector. Note the index marking on the package drawing and on the I.C. in the set. Remove the old I.C. and replace it insuring that the index is closest to the ribbon connector. Inspect to insure all pins are properly in place.
REASSEMBLY
Place the unit upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
AC-201 OR AC-205 MIC. DIODE REPLACEMENT
REMOVING THE AMPLIFIER FROM THE CASE
Remove the cover from the unit, lift out the turntable platter and set it aside. Turn the unit upside down onto a pillow, foam or other material, be sure it is thick enough to support the amplifier and protect the tone arm. Remove the four screws, one near each spring foot. AT THIS POINT THE CHASSIS IS FREE FROM THE CASE AND EXTREME CARE SHOULD BE USED TO PREVENT DROPPING EITHER THE CASE OR CHASSIS. Holding the chassis and the case together, carefully turn the entire unit over to its upright position. The chassis can now be lifted out of its case, lifting the front first so as to clear the jacks on the rear panel.
INSPECTION AND FAMILIARIZATION
Turn the unit upside down on the padding with the controls toward you. The main circuit board is on the right hand side, note how the wires connect to the board and are routed. There are two slotted screws holding the left side of the main board in place. On the right side of the chassis there are 4 slotted screws holding the heat sink in place.
HINGING THE MAIN BOARD OUT FOR SERVICE
1. Remove the two slotted screws on the right side of the chassis closest to the top deck.
2. Remove the two slotted screws on the left side of the main board.
3. Tip the board slightly upward from the left end and unplug the multi-colored cable and the small plug next to it.
4. Place the unit on it's side, with the heat sink down. Hinge the board down un-tucking the remaining cables as needed.
REPLACING MIC DIODES
The microphone input diodes are designed to limit the input signal to normal levels, less than 1v. If a strong signal, ie. line or speaker level signal is put into the mic jacks the diodes may short in order to save the rest of the circuit resulting in a "dead mic channel."
The 8 diodes are located near the mic input jack J2. D1 - D4 are for mic 1 and D5 - D8 are mic 2's. Remove and replace the diodes using vacuum or solder-wick techniques. If you have not worked on 2 sided plated-through pc boards you can cut the leads and tack the new diode on the old leads.
REASSEMBLY
Place the unit upside down on the pad with the controls toward you. Reconnect the two cables removed in step 3. INSPECT THE PLUGS AND INSURE THAT THERE ARE NO PINS LEFT VISIBLE. FAILURE TO PROPERLY ALIGN THE PLUG WILL RESULT IN PERMANENT DAMAGE TO THE LIFTER CIRCUITS. Tuck the other cables in and replace the 4 screws.
Turn the unit over and test it before putting it back in the case.
