Sequential Circuits Prophet-5 Service Manual - Audiofanzine

4-9 FINAL TEST1. Check that the back panel RECORD switch is DISABLEd.2. Press RECORD. It should not light.3. If necessary, load custom or factory programs through the Cassette Interface.4. Select a program.5. Patch SEQUENCER VOLTAGE OUTjack to FILTER CONTROL VOLTAGE IN and check for increasedbrightness across entire keyboard.6. Move connector from FILTER CONTROL VOLTAGE IN to AMPLIFIER CONTROL VOLTAGE IN.Volume should increase as you play up from the bottom of the keyboard.7. Move connector from AMPLIFIER CONTROL VOLTAGE IN to SEQUENCER VOLTAGE IN.8. Patch SEQUENCER TRIGGER OUT to SEQUENCER GATE IN. Check for function and offset.9. Remove both SEQUENCER INTERFACE cords.10. Connect footswitch to RELEASE FOOTSWITCH jack.11. With factory program 1-4 or similar selected, play and check for footswitch function, (SwitchRELEASE off.)RELATED TRIMS: 4-14DAC GAIN, ADC GAIN, AND SEQ INTERFACE4-21 FINAL VGA BALANCE4-22 VOICE VOLUME4-10 POWER SUPPLY TRIMGENERALLY, THE POWER SUPPLY SHOULD NOT BE ADJUSTED UNLESS ITHAS BEEN REPAIRED,READJUSTMENT WILL OFFSET ALL OTA BALANCES, WHICH WILL THEN HAVE TO BE RE-TRIMMED.1. With power off, unscrew the box and slide the top panel assembly forward as discussed inparagraph 1-2, but do not raise to service position.2. For component location see PP531. For schematic, see SD531.3. Switch power on.4. Probe +15V where marked on PCB 5 and adjust R508 to read +15.000V.5. Probe -15 where marked on PCB 5 and adjust R501 to read -15.000V.6. Repeat steps 4 and 5 as required. (It is probably not possible to make these settings perfect.)ITO TRIM, THE SUPPLY MUST BE FULLY LOADED.AFTER REPAIR, CHECK POWER SUPPLY OUTPUT BEFORE INSTALLING, BUT DO NOT OPERATE THEUNLOADED SUPPLY FOR LONG PERIODS WITHOUT HEAT-SINKING THE REGULATORS. NEVEROPERATE THE SUPPLY UNDER LOAD WITHOUT HEATSINKING.WHEN INSTALLING, BE SURE REGULATOR TABS ARE FLAT AGAINST THE HEATSINK AND THE MICAINSULATOR IS WELL-COATED ON BOTH SIDES WITH THERMAL COMPOUND. BEFORE APPLYINGPOWER, CHECK REGULATOR INSULATION FROM BACK PANEL WITH OHMETER. ALL OUTPUTSSHOULD READ "INFINITE" RESISTANCE.4-9