Black Jupiter 2000 Function generator circuit.

[johnmcgivern]

I notice from the datasheet that the service manual didn't come with the Jupiter but was listed as an optional extra, so might not be very commonplace, but hopefully one will turn up. Without a circuit, a few preliminary checks could at least be made - for example, the voltages/ground connections of the ICs. Given the era in which it was made, though the blurb refers to it using a 'microprocessor' I wonder if it used the then popular but long since obsolete 8038 waveform IC? If so, they do sometimes turn up on internet (eBay etc). Any electrolytics may by now have high ESRs but whether that would stop it working is debatable.

There is a schematic available FOC from this site, but you have to register to get it, but I know nothing about the site - 'ride at your own risk'!:

http://documentsearch.org/pdf/black-star...matic.html

Best of luck in your quest John.

Thanks for replying Yorkie there is no 8038 chip but these are the chips on board.
CA 3089 NPN transistor array.2 off.
DM74LS37N Quad 2 input nand buffers. 1off.
NE527 Voltage comparator. 1off.
071CDP Op amps. 4off.
072CDP Opamp 1off.
Variable resistor15 off ha ha.
I,ll have a go at checking voltages and gnds.
T/F centre tapped 18v either side 36 in all no markings on T/F to check specs.
I am just a novice I was using the generator to do rf alignment on a Pilot u650 1936 radio resoration nothing seemed to be happening so hooked up to scope and there was no amplitude on signal I had bought the scope on ebay hardly ever used it sods law I only bought it to try and learn how to use it not repair it ha ha.
I tried the site for schemeatic registered then they asked for money I hate it when they make out its free so never bothered. I started this Pilot restoration about 9mths ago was warned about the bug but I am afraid I got it can,t leave it alone now ha ha. Learning all the time wish I had started 50years ago.
Many thx, John.