to make the 39 volt voltage rise slowly... this will save your VU meter lamps
and will stop loud pops in the audio system on Turn On.
Parts required:
1 each MJE2955 transistor
2 each 1N4004 diodes
1 each 100uf/100 volt small size radial lead cap
1 each 22k ohm resistor
1 each circuit board - Radio Shack has small ones
a 1 inch or so, 2 watt resistor lead, cut off from any 2 watt resistor
Small wire to connect board points to machine
NOTE: You must be able to solder well and know how to find the correct
transistor and diode pins !!!
1) There is on the inside rear of the main power supply a small Terminal Strip
and soldered onto this is a 82uf cap, usually silver in color
(TS3 on schemaitcs and parts locator, the cap is C3)
On the circuit board build the following circuit:
Remove the 82uf cap (C3) Note the Positive and Negative cap connections !!!
Solder in the connecting wires to the old 82uf cap points
and find the large screw terminal Cap C1, attach wire to C1 Positive
Cut off and Bend a piece of a large watt resistor lead
and loop this long enough so you can solder the two ends
to the circuit board and have enough length to solder the loop
to the Free lug on TS3 to hold the circuit board in place.
Make sure there is no connection to the circuit - this is just
a simple way to mount the circuit board.
Now once you turn ON the machine, the 39 volt power should
slowly ramp up - you will see the VU meter lamps slowly turn on
which indicates you've done the correct procedure.
Please check and adjust the 39 volt voltage system
more tricks will be added from time to time, so check back now and then!