That would be the good outcome, albeit with some crossover distortion. If there's no recurring fault protection, then focus shifts to Q35 and nearby components.
I confess I was hoping for more.
What are voltages across C39, C40? And amp output voltages? Earlier, you reported 1.3V across C39. What was different then versus now?
If you happen to be testing without speaker, you might load output with 10K to absorb any off-state leakage currents.
What are voltages across C39, C40? And amp output voltages? Earlier, you reported 1.3V across C39. What was different then versus now?
If you happen to be testing without speaker, you might load output with 10K to absorb any off-state leakage currents.
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The DC is about 5mv on *left and about -18mv on right after a few seconds. Right is faulty.
yes audio comes after power off briefly
yes audio comes after power off briefly
Please correct me if I'm wrong:
Left chanel shows better behavior than right channel.
C39 has 1.3V. C51 has not been fitted with a short.
Output is about +5mV.
Right channel has C40 0.1V. C52 has installed short for test.
Output is about -18mV. With speaker as load
I was/am expecting audio on left channel but fault on right only. Still perplexed.
On the working left channel, would measure the voltage across C51?
Left chanel shows better behavior than right channel.
C39 has 1.3V. C51 has not been fitted with a short.
Output is about +5mV.
Right channel has C40 0.1V. C52 has installed short for test.
Output is about -18mV. With speaker as load
I was/am expecting audio on left channel but fault on right only. Still perplexed.
On the working left channel, would measure the voltage across C51?
Must be very late in London. I'll look for an update in morning here in the states.
I'll likely be absent around a month. By the time I return, you'll have it fixed!
Good luck!
I'll likely be absent around a month. By the time I return, you'll have it fixed!
Good luck!
Yup 2:30am. Im a night owl LOL
I cant even follow instructions and nearly blew myself up. Unless someone else offers help I'm not really left with much options but wait 🙂
I cant even follow instructions and nearly blew myself up. Unless someone else offers help I'm not really left with much options but wait 🙂
I may have very occasional connection, but can't predict.
If C39 has 1.3V, it suggests the amp is active and ought to pass audio. I would estimate about 1.8V across C51 if active. A few mV across R107A per page 27 in the manual would be another sign of health. Try to confirm audio is present at amp input if still no sound.
Similar comments should apply to the other channel.
If C39 has 1.3V, it suggests the amp is active and ought to pass audio. I would estimate about 1.8V across C51 if active. A few mV across R107A per page 27 in the manual would be another sign of health. Try to confirm audio is present at amp input if still no sound.
Similar comments should apply to the other channel.
So you're using phono section as signal source to test output stages?
I'm trying to refresh my memory. I believe I was thinking left channel (odd number Ref Des) might be working and should deliver audio, but that right channel was in fault shutdown. I was looking for evidence of nominal bias on left channel, i.e. items in #57. If these looked nominal, audio should be delivered to speaker.
I'm trying to refresh my memory. I believe I was thinking left channel (odd number Ref Des) might be working and should deliver audio, but that right channel was in fault shutdown. I was looking for evidence of nominal bias on left channel, i.e. items in #57. If these looked nominal, audio should be delivered to speaker.