he should invest in a low
cost esr meter from mat electronics
ive had one of theirs for
several years and its very usefull when going
through a piece of equipment
just remember that a
shoted lytic shows a low esr so i test
lytics in circuit with a low power ohmmeter
too.
----- Original Message -----From: Frank SimonSent: Wednesday, June 30, 2010 6:56 AMSubject: Re: [vintagesynthrepair] Re: Prophet 10
OK, That's what I'm after. Mine does hum but the Regulated voltages are all correct. I did make a comment on ripple but not so sure that is an issue. I would like to move on to the computer board after I bless the PSU. Can anyone guess why sometimes the the LEDs light and and somtimes they don't? Does that seem to be Processor related? I would rather chase audio. Also can I unplug all the boards off the Computer board except power for troubleshooting?----- Original Message -----From: Miguel MendozaSent: Wednesday, June 30, 2010 4:59 AMSubject: Re: [vintagesynthrepair] Re: Prophet 10
I don't hear any hum in my Prophet 10From: Frank SimonSent: Wednesday, June 30, 2010 5:30 AMSubject: [vintagesynthrepair] Re: Prophet 10
Are there any Prophet 10 owners that can answer a question for me? Can you hear your transformer hum when you power up?Frank----- Original Message -----From: Frank SimonSent: Monday, June 28, 2010 11:24 PMSubject: Prophet 10My P10 is wacko. Sometimes I turn it on it lights up and acts like it wants to work but if I cycle the power nothing will light except the tune LED as if it is in tune mode but doesn't time out. If I cycle power something different may happen. I think the PCB3 board has issues would anyone agree? All Power supplies are good with DVM but I see noise ripple on supplies with .2 to .5V that seems high to me. It is not 60 cycle ripple but very random noisy ripple. Not sure of best trouble shooting approach of this board. My P10 shematic is freeby with poor zoom in ability. My P5 is better but refernce designators and power supplies seem different. Anybody got a good service manual or advice?Frank