Hey all Im working on an eclipse amp and having trouble finding the problem. Powers on, no sound. Verified DC voltage on output @ 42v with variations in the wave form, not sure if thats normal as Im still learning and I know the O-scope is cheap garbage. I checked the NPN and PNP both are good but needed to be soldered back in the board for some reason they were both lose. I don't see anything visibly burned.
Yep, Ill follow the traces again but oddly there's nothing. Ill try a different source to be sure. Thanks Perry.
Is the ground/non-bridging speaker terminal connection broken? It should read 0 ohms to the secondary ground.
Yea this has me stumped. I can see signal on the outputs of all 4 speaker terminals while playing tones or music showing at 30v but when adding a speaker to it I get nothing. I checked the input signal its good and the speaker being used is good. The npn/pnp get warm nothing else does, fets are cold like everything else..
Nothing shows? What does that mean?
If there is rail voltage on the center output terminal, you should read 0 ohms from the third terminal of those outputs to one of the speaker terminals.
Start at the speaker terminals and work backwards towards the outputs to see where the connection is lost.
If there is rail voltage on the center output terminal, you should read 0 ohms from the third terminal of those outputs to one of the speaker terminals.
Start at the speaker terminals and work backwards towards the outputs to see where the connection is lost.
Sorry yes there's 0 ohm (using continuity DMM) from speaker outputs to the third legs of the output fets.
If you have output on the third leg and it's reaching the speaker terminal, that would tend to indicate that there is a broken connection on the ground/non-bridging speaker terminal. What'e the resistance from those terminals back to the secondary center-tap of the transformer?
Yep, I did this and traced back to some NEC K3057 which appear to working with 80v on the left and middle legs and 68v on the 3rd leg. I didn 't see any melted traces.
You should read 0 ohms from the non-bridging speaker terminals to the point indicated by the green arrow. Are you saying that you read 0.8 ohms to that point?
What do you read when you touch the probes together?
The 2SK3057s are the PS FETs. You should't read 80v on any terminal. The expected readings are about 6v, 14v and 0v reading with a multimeter on DCV.
What do you read when you touch the probes together?
The 2SK3057s are the PS FETs. You should't read 80v on any terminal. The expected readings are about 6v, 14v and 0v reading with a multimeter on DCV.
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Probes touched on continuity read .000, touching the spot you pointed to and the non bridging reads 0.
Don't use continuity mode. It gives meaningless results unless you're testing a fuse or incandescent lamp. .
What were the readings you previously posted 0.7... and 0.9.,..?
What were the readings you previously posted 0.7... and 0.9.,..?
I'm trying to ensure that the numbers you're posting are reliable. Unless you have a high-end meter, it's not going to read places to the right of the decimal. If your meter isn't auto-ranging, set it to the lowest range and check again.