Elenco Digital / Analog Trainer Kit Version - Manual (Page 18)

VOLTAGE ANALYSIS OF POWER SUPPLY
Proceed with the voltage analysis only if the resistance readings were satisfactory.
Place the top panel on the unit. If any capacitors are inserted backwards, the panel will shield you if
they explode. Make sure that the ON/OFF switch is in the OFF position. Plug the line cord into the 120VAC
power source. Turn the unit on and let it sit for a few minutes. Turn OFF the ON/OFF switch and remove the
top panel, placing it along the left side of the trainer. Turn ON the ON/OFF switch and measure the voltage point
as listed in the chart below. The values given are approximate.
See Figure O for locations of the testing points.
From To Circuit Volts Volts Measured
15 GND +12V Regulator Input +21V
B3 GND +12V Regulator Output +12V
16 GND –12V Regulator Input –21V
B2 GND –12V Regulator Output –12V
17 GND +5V Regulator Input +12.5V
B4 GND +5V Regulator Output +5V
18 GND +20V Regulator Input +28V
25 GND Voltage ADJ +20V Regulator CCW 0V CW +18V
+20
5-pin connector
GND +20V Output CCW +1.25V CW +20V
19 GND –20 Regulator Input –28V
26 GND Voltage ADJ -20V Regulator CCW 0V CW –18V
–20
5-pin connector
GND –20V Output CCW –1.25V CW –20V
15VAC 15VAC 30VAC 30VAC
5-pin 5-pin
connector connector
left right
+30% CCW - Counter-Clockwise CW - Clockwise
Turn unit off.
-17-
FUSE REPLACEMENT
1. Turn the trainer off and unplug it from 120VAC power source.
2. Unscrew fuse holder cap and remove fuse.
3. Use only a 1.25A fuse. Larger fuses or other fuse bypass will void the
warranty of the trainer.
4. Place the new fuse into the fuse holder cap and screw it back into the holder.
5. Plug trainer into 120VAC power source and turn the unit on.
Place the top panel on top of the unit.