[sdiy] Schematics for Peavey Spectrum Synth

[Music ARTxTEK]

Greetings


I am wondering if anyone has schematics for the Peavey Spectrum Synth.

I just replaced the memory backup battery and did a memory reset/initialisation and the unit was working fine, then I noticed that the 5V voltage regulator was starting to heat up, then the display and LEDs started to flicker and the unit was no longer working.


I tested PSU, +15V is ok , but -15V is running at -7V and the +5V is reading 0.3V - all measurements from the voltage regulator output pin.


As I understand it from other synths, the 5V is for the logic chips and the +/-15V is for the audio side.


At the moment I am thinking that either capacitor(s) have failed or one (or more) of the 74HC or HCT  have failed and are shorting the 5V PSU, although the -15V issue maybe capacitor failure.


Anyway, if anyone has schematics I would be grateful.


Regards Tony.

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