Perry,
Will the 4080 show a wave form if I have a signal driving the input? I havent seen a waveform that I would expect on the ps our output side. But the ps still seem to be producing the proper rail voltages. There is an interesting dip8 chip on a vertical riser board. What is it? seems to get warm as compared to everything else .
Will the 4080 show a wave form if I have a signal driving the input? I havent seen a waveform that I would expect on the ps our output side. But the ps still seem to be producing the proper rail voltages. There is an interesting dip8 chip on a vertical riser board. What is it? seems to get warm as compared to everything else .
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Okay will check. Funny about the output fets. paperwork says STP50NE10 were replacing the with the 3710Z and the silkscreen on the board says RFP40N10's which didn't seem very unavailable or expensive. Does the resistance value stay the same for either of the substitutes. This amp has been worked on before wonder why the RFP40N10 were phased out in the first place? Never looked at the ps fets as it seems to work but it is noted that the fets there are RPF70N06's
like the same call numbers as the silkscreening there.
like the same call numbers as the silkscreening there.
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When I go from any original output FET to the 3710Z, I leave all resistor values the same.
I can't explain why but the new (original part number) FETs won't work as the old ones. I thought it might be changes in the 4080 but pulling 4080s out of amps working with the old FETs and installing them in amps with the new FETs wouldn't work.
I can't explain why but the new (original part number) FETs won't work as the old ones. I thought it might be changes in the 4080 but pulling 4080s out of amps working with the old FETs and installing them in amps with the new FETs wouldn't work.
Perry,
I ruined a pin on insertion so I wait for another Hip. Should be here Monday. Im a bit nervous this isn't the problem. I hope I didn't get bogus 3710z from the german supplier. Always trying to cut a dollar should have just gone IR direct but until now hadn't had any issue with bogus fets.
I ruined a pin on insertion so I wait for another Hip. Should be here Monday. Im a bit nervous this isn't the problem. I hope I didn't get bogus 3710z from the german supplier. Always trying to cut a dollar should have just gone IR direct but until now hadn't had any issue with bogus fets.
Hi Perry,
I manage to get the new 4080 installed without any mishaps. The amp now light with only the left led in photo. But it still seems something is not right. I haven't checked for audio but the power supply seems to get warmer than id expect just sitting at idle.Not on fire but warmer than id think for idle.I do notice the toroids seem exhibit an audible screeching sound while powering up up. Where would you go from here? Can you tell me exactly what each led represents? The lettering has been long gone. Did I get stuck on the 3710Z's you think?
Hugh
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