The only ones I could find that the board was slightly burnt light brown around solder joints on the 2N5401 all other drivers appear to be ok A06 A56 A93
Replaced the 3 2N5401 drivers today but did not seem to do any good they appear to be running really hot idling which could be normal
also in lined with 8099 like in your picture Perry 4 resistors in this circuit appear to be stressed discolored but not completely burnt like one of the resistors in the picture you provided in this post the other 3 resistors appear to be the same ones in your picture that are discolored same exact locations but for some reason I have tested all bjts in this area and I just don't seem to find any issues with them they are not shorted the readings appear to be within spec as well
Is there a possible defective ic that controls the preouts for the subs that could be defective you wouldn't happen to know where that would be located would you Perry
Also I have replaced the sub outputs with the irf3415 fets I can sometimes messing with one of the freq pots get the littlest sound coming from the speaker when the pot is turned
Also after replacing the 2n5401 I noticed there was a pulsing sound coming from all channels even the working channels but that could be like you said the sub and full range portion of this amp is tied together
With the IRF3415 removed also I noticed the drivers 8809 2n5401 and the resistors mentioned were still getting hot just running channels 1-4
Do you know if the drivers also are tied together with all 5 channels Perry?
also in lined with 8099 like in your picture Perry 4 resistors in this circuit appear to be stressed discolored but not completely burnt like one of the resistors in the picture you provided in this post the other 3 resistors appear to be the same ones in your picture that are discolored same exact locations but for some reason I have tested all bjts in this area and I just don't seem to find any issues with them they are not shorted the readings appear to be within spec as well
Is there a possible defective ic that controls the preouts for the subs that could be defective you wouldn't happen to know where that would be located would you Perry
Also I have replaced the sub outputs with the irf3415 fets I can sometimes messing with one of the freq pots get the littlest sound coming from the speaker when the pot is turned
Also after replacing the 2n5401 I noticed there was a pulsing sound coming from all channels even the working channels but that could be like you said the sub and full range portion of this amp is tied together
With the IRF3415 removed also I noticed the drivers 8809 2n5401 and the resistors mentioned were still getting hot just running channels 1-4
Do you know if the drivers also are tied together with all 5 channels Perry?
Also I do remember before switching the output fets 65n06 with the 3415 the speaker was making a pulsating sound through all channels even the sub channel not sure if that says there was oscillation or not Perry I will have to test that this weekend when I have time to hook up my scope
HF? If you're referring to the timebase, you'll have to set it to either 5 or 10uS to see individual pulses but you'll see the r-r oscillation on any setting.
sorry Perry I was referring to the coupling setting that has
AC
LP Rej
HF Rej
DC
Do I need to set that to LP rej
AC
LP Rej
HF Rej
DC
Do I need to set that to LP rej
The signal is large enough that it should not matter if the trigger level is set correctly. If you cannot get a lock and you can see that there is rail-rail oscillation, try the various trigger coupling settings, adjusting the trigger level after each change.
Ok thank you Perry ill check that out this weekend soon as I get the chance and see what I come up with
Not sure if I have something hooked up wrong Perry I just get the trace line when set to 5us and 10us probe on middle pin of the 3415 and ground is attached to the amps ground terminal I have tried various settings but still no wave
Do I need to make a resistor load like in part of the post you sent me?
Do I need to make a resistor load like in part of the post you sent me?
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Touch the probe to the tabs of the power supply FETs to confirm that you have the correct settings on the scope.
The r-r oscillation will be on leg 3 of half of the outputs and leg 2 of the other half of the outputs in the class D section.
The r-r oscillation will be on leg 3 of half of the outputs and leg 2 of the other half of the outputs in the class D section.
there is only 2 3415 Perry for outputs in the class D section so would that change the pins to probe ?
also do I still need the ground on the ground terminal of the amp ?
also should I still get oscillation through the outputs if I am not playing music
also do I still need the ground on the ground terminal of the amp ?
also should I still get oscillation through the outputs if I am not playing music
It doesn't matter if it's half of 10 or half of two.
If your scope and 12v power supply both have 3-prong plugs, their grounds should already be connected unless the ground is faulty in in one or both. I only VERY rarely use the ground clip on my probe. Actually, the probe I use isn't shielded and has no ground.
Some amps won't reliably oscillate until the amp sees a signal.
If your scope and 12v power supply both have 3-prong plugs, their grounds should already be connected unless the ground is faulty in in one or both. I only VERY rarely use the ground clip on my probe. Actually, the probe I use isn't shielded and has no ground.
Some amps won't reliably oscillate until the amp sees a signal.
Thanks for your help Perry problem has been resolved you was right I double checked all values of each BJT in the driver side of the sub outputs and one of the A06 bjt's voltage values was seemed low so I swapped that out and the sub output works great now the 3415's seem to work perfect they don't even get hot hot
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