Ok I just want to double check with some of the experts on here. I have the PCB 100006 Rev 3 version. I tried to put all the info I could down.
I have discovered a 2 of the outputs are fried which in turn fried other stuff. I just want to double check, and make sure I'm ordering the correct parts. I found the power supply FETs. I need to measure the gate resistors for their physical size although I do know they are 47 ohms (47R0), and I believe they are 1/4w... I think... Also discovered a few output resistors are bad as well. Thanks to the other threads I came across on this site! Awesome information out there, but these 2 items I have not came across yet.
Starting with the outputs I noticed the outputs are IRF540's, but there is 2 different ones. The right one is hard to see. IRF540 048E on the left, and IRF540 1055 on the right. Is there a big difference between the 2? I've came across lots of IRF540's, but not these 2 exactly. Maybe I'm just not searching correctly or something.
Then I've read on multiple threads different part numbers for these the driver transistors... which I can not seem to locate by the printed part letters/number on my own. I've seen the part numbers KTA1666, 2SB1260, 2SD1898, etc. But everyone just shows the UY and UW. Not the numbers. So I figured I'd ask to make sure I'd get the correct compatible ones. Also then which ones which as one is a PNP and the other is NPN correct?
I have discovered a 2 of the outputs are fried which in turn fried other stuff. I just want to double check, and make sure I'm ordering the correct parts. I found the power supply FETs. I need to measure the gate resistors for their physical size although I do know they are 47 ohms (47R0), and I believe they are 1/4w... I think... Also discovered a few output resistors are bad as well. Thanks to the other threads I came across on this site! Awesome information out there, but these 2 items I have not came across yet.
Starting with the outputs I noticed the outputs are IRF540's, but there is 2 different ones. The right one is hard to see. IRF540 048E on the left, and IRF540 1055 on the right. Is there a big difference between the 2? I've came across lots of IRF540's, but not these 2 exactly. Maybe I'm just not searching correctly or something.
An externally hosted image should be here but it was not working when we last tested it.
Then I've read on multiple threads different part numbers for these the driver transistors... which I can not seem to locate by the printed part letters/number on my own. I've seen the part numbers KTA1666, 2SB1260, 2SD1898, etc. But everyone just shows the UY and UW. Not the numbers. So I figured I'd ask to make sure I'd get the correct compatible ones. Also then which ones which as one is a PNP and the other is NPN correct?
An externally hosted image should be here but it was not working when we last tested it.
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2SD1898T100R and 2SB1260T100R should work as Perry has used the PNP with no issues.
The fets are like that from the factory batches...I've seen it on plenty of new untouched amplifiers (not the same batch).
When replacing them make sure you match them and replace all of them (all four).
Yes its a 47ohm resistor.
The fets are like that from the factory batches...I've seen it on plenty of new untouched amplifiers (not the same batch).
When replacing them make sure you match them and replace all of them (all four).
Yes its a 47ohm resistor.
Awesome! Thanks for the links even! Now is the UY a PNP or NPN... that way I know which is which.
With the output fets it doesn't matter that each side has 2 different "model" or "version" numbers? IRF540 048E and IRF540 1055
Yeah I know how to tell which part is PNP and NPN... I'm asking about the factory driver transistors thay are still on the board. The UY 112 and WY 111 or will the new parts have the same stamping? The part I don't know is if the UY 112 is a PNP or NPN, and if the WY 111 is a PNP or NPN. Maybe I'm just being special?
/\ ignore that post... I can't edit it to delete it or I would.
In the picture below this is only for "1 side" there is actually 2 more of those same part numbers (not pictured). I took this close up for the letters/number on the transistor itself so it was visible. I can upload a picture of that section of the board and try to highlight all 4 if needed. Also don't be afraid to tell me i'm being an idiot. It's been about 5 years since I've messed with circuitry lol! I do see which part on mouser is the PNP and which one is the NPN, but still does not answer my question. When I get these parts I don't know which to replace what with.
Maybe this will help clarify what I'm asking.
2SD1898T100R is the replacement for UY 112?
2SB1260T100R is the replacement for WY 111?
or vise versa?
In the picture below this is only for "1 side" there is actually 2 more of those same part numbers (not pictured). I took this close up for the letters/number on the transistor itself so it was visible. I can upload a picture of that section of the board and try to highlight all 4 if needed. Also don't be afraid to tell me i'm being an idiot. It's been about 5 years since I've messed with circuitry lol! I do see which part on mouser is the PNP and which one is the NPN, but still does not answer my question. When I get these parts I don't know which to replace what with.
Maybe this will help clarify what I'm asking.
2SD1898T100R is the replacement for UY 112?
2SB1260T100R is the replacement for WY 111?
or vise versa?
An externally hosted image should be here but it was not working when we last tested it.
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alright so... it's done for. I pulled up the pad on one of the driver transistors. 
damn. well thanks for the help. looks like my desoldering skills are horrible. the iron was only 500* too. ugh. well thanks for the help. I might try another amplifier I have, but it sucks that I just bought 60 dollars worth of parts then this to happen. I'm saddened by my error.
damn. well thanks for the help. looks like my desoldering skills are horrible. the iron was only 500* too. ugh. well thanks for the help. I might try another amplifier I have, but it sucks that I just bought 60 dollars worth of parts then this to happen. I'm saddened by my error.Its not too late...if your pretty handy with a soldering iron you could jump a wire to the smd driver.....but then again you did say you damaged it yourself
Post pic of the damage and we might be able to tell if its repairable or not.
SMD parts are best to be removed with a SMD rework soldering station which using hot air to heat up the SMD component leads and solder pads. Once you got it hot enough you can easily pick it up with a fine pair of tweezers. Take it as a lesson learned, buy a SMD rework station (only if your serious about doing future repairs, because they are NOT CHEAP unless their knock offs) and practice on a scrap board.
.....but then again you did say you damaged it yourselfPost pic of the damage and we might be able to tell if its repairable or not.
SMD parts are best to be removed with a SMD rework soldering station which using hot air to heat up the SMD component leads and solder pads. Once you got it hot enough you can easily pick it up with a fine pair of tweezers. Take it as a lesson learned, buy a SMD rework station (only if your serious about doing future repairs, because they are NOT CHEAP unless their knock offs) and practice on a scrap board.
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the long leg that goes under the driver transistor the whole thing was pulled up trying to fix a bridge I did when my hand twitched. I remember this being easier before.... then again I also had an air soldering iron for this small stuff. I'll take a picture, but no idea how well it will turn out.
An externally hosted image should be here but it was not working when we last tested it.
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That's easily repairable buddy, so don't even trip or worry about it. You see that via hole that has the trace you damage? Remove any solder present there, and clean it up real good, flux and slide a small strand of wire...solder it then leave enough to solder the other end to the smd transistor.
Check the continuity of the trace you repaired and if its good them no need to worry about it, if its not making proper connection see where that trace leads to (hopefully a through hole component so you can jump a wire from there to the smd transistor.
Check the continuity of the trace you repaired and if its good them no need to worry about it, if its not making proper connection see where that trace leads to (hopefully a through hole component so you can jump a wire from there to the smd transistor.
I don't have any wire that small... that's a TINY hole. I think I'm going to give up on this one. There's 2 holes on the power supply that are iffy... I think I royally screwed this one up. I can solder (put it together) pretty well, but desoldering I can't seem to do without screwing everything up. ugh. Thanks for your help though.
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See where that trace leads to...double check it with your dmm in continuity mode (or beep/diode) then add a jumper from the nearest component it leads to....to the smd transistor.
I have one laying in the back, I'll check it out and confirm a good place to add the jumper wire... just let me know exactly which driver it is (Q***)
I have one laying in the back, I'll check it out and confirm a good place to add the jumper wire... just let me know exactly which driver it is (Q***)
May be too much heat....or you pulled the transistor too soon and caused damaged to the pads. Either way its repairable but will be a PITA. Good luck and let me know if you want those locations for jumpers, lol.
If your really patient and careful you could scrap off a bit of that green enamel off those traces and use 1/16th solder wick to jump those traces. its possible just have to be very patient and have a nice small fine iron tip.
If your really patient and careful you could scrap off a bit of that green enamel off those traces and use 1/16th solder wick to jump those traces. its possible just have to be very patient and have a nice small fine iron tip.
Call it a day and take a break, don't sweat it. You can always use it for parts (RCA's, heat sink clips, if chassis is mint then I might be interested it in).
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