If all drive signals look OK, are running the same temperature and there is no problem when twisting the inductors, it's likely OK. One of the biggest problems is damaging the drivers when installing them. If they survive being installed and you find all of the other defective parts, the amp is generally safe to power up normally.
Keep that low-voltage supply. It can save a lot of headaches on amps that need rail voltage for their drive circuits. I think you'll see that the little bit of time it takes to install are worth the effort.
As a side note, more windings (than the starting 5 turns) will produce enough voltage to burn out the 12v lamps if something causes excessive current draw. That's why I use sockets.
Keep that low-voltage supply. It can save a lot of headaches on amps that need rail voltage for their drive circuits. I think you'll see that the little bit of time it takes to install are worth the effort.
As a side note, more windings (than the starting 5 turns) will produce enough voltage to burn out the 12v lamps if something causes excessive current draw. That's why I use sockets.
Yes the LV supply is a great tool and I will definitely use it whenever it's needed thanks for your patience and knowledge
I'm going to put rectifiers back in and check drive signals again an I'll have an update asap
I don't know if all defective parts are found but everything tested so far seems fine maybe it's a protecting circuit issue cause amp seems ok with it disabled
I'm going to put rectifiers back in and check drive signals again an I'll have an update asap
I don't know if all defective parts are found but everything tested so far seems fine maybe it's a protecting circuit issue cause amp seems ok with it disabled
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You can reliably check most all parts on the board with your meter and check for proper operation at low voltage.
The only thing you can't do is check for insulation issues on the inductors. Obvious problems, broken insulation can generally be found (by twisting/pushing/pulling) but weak insulation problems may only show up at high voltage when it arcs through.
The problem with that is that an intermittent short at high voltage can undo all of the hard work you just did and put you back at square-one. That's why I hate these amps.
The only thing you can't do is check for insulation issues on the inductors. Obvious problems, broken insulation can generally be found (by twisting/pushing/pulling) but weak insulation problems may only show up at high voltage when it arcs through.
The problem with that is that an intermittent short at high voltage can undo all of the hard work you just did and put you back at square-one. That's why I hate these amps.
Ok Perry here's an update so after trouble shooting I found C13 on the power supply driver board (pic below) it had a lifted/snapped trace so I fixed it and with dmm on continuity mode it went from the positive side of that cap to pins 13-15 On the tl494.
I put R21 back in it still powered up fine and played audio so then I placed Q226 back in an the amp seems to be ok it's staying on drive waves look great on all fets no heat issues still alil whine but otherwise seems ok!
Any thoughts or worries on your end I should look at?
I put R21 back in it still powered up fine and played audio so then I placed Q226 back in an the amp seems to be ok it's staying on drive waves look great on all fets no heat issues still alil whine but otherwise seems ok!
Any thoughts or worries on your end I should look at?
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I'm not 100% sure Perry I guess what I'm saying is I've checked everything else I can pull off the board and everything reads good and the C13 capacitor was the only issue I had found
I thought maybe the lm393 was at fault for the protection circuit but maybe it was the C13 cap on pin 15 of the EA2 ?
Amp is on playing fine other than a little whine so what I'm trying to say is do you think that cap could have been the culprit it was a intermittent connection when pad pulled up it appeared to sever the trace but it was close enough to where if you would wiggle the board it would connect
I thought maybe the lm393 was at fault for the protection circuit but maybe it was the C13 cap on pin 15 of the EA2 ?
Amp is on playing fine other than a little whine so what I'm trying to say is do you think that cap could have been the culprit it was a intermittent connection when pad pulled up it appeared to sever the trace but it was close enough to where if you would wiggle the board it would connect
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I think I found the main issue one of the old output fets was reading 215 ohms from drain to source so when the old fets were in I think that's why it kept going in protect and when I took them out and did only one per bank it fixed the problem because it wasnt in the group used to test
I feel like a goober for over looking that I thought I had tested them all in the amp but could have read all the others were fine and skipped it idk if it had went bad while trying to test though but thought I would tell you what I found when tested the old fets on my transistor tester so it may help someone else to slow down and make sure you test everything before all this
I feel like a goober for over looking that I thought I had tested them all in the amp but could have read all the others were fine and skipped it idk if it had went bad while trying to test though but thought I would tell you what I found when tested the old fets on my transistor tester so it may help someone else to slow down and make sure you test everything before all this
Thanks you so much Perry for all the help im still kind of a noob and as much as I hate making noob mistakes it's part of learning and i appreciate all the patience and knowledge from you it was a great learning experience for me.
Do you have a PayPal so I can donate a little money for your time?
Do you have a PayPal so I can donate a little money for your time?
Still having the squealing noise issue amp plays good but has a noticeable squealing noise so I've been trouble shooting and have found 2 smd transistors that may be shorted but can't tell or find out what they are I've tried Google and the smd code book but can't seem to find it any help would be greatly appreciated
AND TRANSISTORS READ (W6P 0) pic below
AND TRANSISTORS READ (W6P 0) pic below
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