On Sun, Oct 25, 2015 at 10:46:54PM +0000, Lee Borrell templarser@... [CZsynth] wrote: > Yes - The main CPU is operating and producing signals as it should on the oscilloscope with the PSU at the power pin.Everything works - including the backbone connector between the circuit boards. There is just no LED response and a weak output from the MIDI socket. > The processor seems to be producing MIDI ok and producing the LED signals from the addressing pins. > To me it looks like the MIDI output stage tranny is not doing its job - and something is either wrong with the LED power source (which is separate from the analogue and digital sources) or the whole LED driver stage has failed (which does not seem likely). I am pretty certain there is a working AZ in there waiting to come back to life. > Right, but what's the actual supply to the MIDI driver tranny and LED drivers looking like? -- Gordonjcp MM0YEQ
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Re: [CZsynth] AZ1 repair
2015-10-25 by Gordonjcp