ONKYO TX-SR502 RECEIVER "SHORTED CHANNEL REPAIR"

ONKYO TX-SR502 RECEIVER "SHORTED CHANNEL REPAIR"

[@jamesatkinson6480]

Nice de-soldering toy; I want one for Christmas! It looks like those transistors are of the bi-polar type. There is now research on insulated-gate bi-polar transistors, where the benefits of each type (mosfet & bipolar) are enjoyed; I would be checking/comparing the driver stages prior to the installation of the new parts; even if it means de-soldering another power stage's ok power transistors.. Thanks for the post, and hope your neighbor continues to enjoy its use!! A real head-scratcher for myself was one of these where the protection circuitry was activating after a long period of the amplifier being 'on'. I ended up replacing all of the small-signal plastic transistors on the protection circuit, and fixed the problem..

[@adammeway6310]

Picked up a Onkyo HT-RC260 for $20 on craigslist that was stuck on standby mode. Tested the same parts in this video and they where bad, ordered new parts, some on ebay and the others from local radio repair shop. When all was said and done i repaired it and it now works. Thanks for the helpful video.

[@jimholloman4457]

When working on any AV Receiver, I recommend using a Variable Transformer to restrict the AC current or else run the AC thru a 75-100 watt incandescent light bulb. It can help prevent another power transistor from being popped if something else in the circuit is bad and overloads an output transistor.

[@robertcrawford7737]

As long as you're changing the power output transistors and the emitter bias resistor, you better change the driver transistors too or you'll be opening that beast up again soon. ALWAYS change the drivers when you change the outputs.

[@solveityourself2158]

Robert Crawford sir..i m having same problem.. could u please tell which are drivers.. so that i can change them too

[@tracystratton1375]

Where can I order transistors from

[@habsrepariert]

This post is a little older, but for those that look for the driver parts that need to be changed, have a look over here : kzbin.info/www/bejne/o5rWpmeXq9ySjNU

[@swrzesinski]

There is only one option: resistors dont open up by no reason. There must be collector-emiter breakdown of the output stage transistors, excesive current flowed thru emiter resistors that burnd them.

[@brettlong8952]

Really appreciate this video. I bought a "broken" Onkyo TX-NR636 with the "check sp wire" error earlier this week. After scouring the internet I found this video and isolated the issue and removed the transistors and the receiver works great! Now I only need to order the replacement transistors and install. Great tutorial video!

[@thersten]

I have what looks like a burned noble resistor, but how did you figure out which transistors were bad?

[@justinberry3991]

​@@therstenmultimeter

[@lcagee]

Awesome video. I've been trying to repair a subwoofer plate amplifier. 200 watt. I saw 2 fried transistors that I replaced. Didn't even think about a fried resistor. And I didn't even know there were 3 pronged resistors. Also there was a ceramic disc that looked cracked. Finally figured out it was a current limiting thermistor. Will replace that. It was still blowing fuses so I'll look for a blown resistor. My guess is the volume was turned up too high for too long, the transistors shorted leading to a current surge frying the thermistor.

[@RYENZRO]

I repaired a blown channel on my TX-SR806 thanks to your video. I'm having one hell of a time finding the right power resistor, though. For the time being I stole one from an unused channel. Works like a charm.

[@RYENZRO]

+land otter1 thanks for the reply. I ended up finding a component re-seller out in California and bought a small lot of these components. So if anyone needs dual emitter 5W 2ohm MPRs to repair their Onkyo send me a PM.

[@jasoneyes01]

Thanks Mark! Actually working on an M504. A numb head decided to leave some screws out of the heat sink support. During shipping the board was cracked. When I recieved it I turned it on and BANG! I saw flares inside the cover. Lost one of the output transistors and about 10 components on the driver section on the left channel. Anyways I epoxied the board and ran about 5 jumpers. The 2SK389 is a temp componsation transistor which was on fire during the incident.Im almost done with the repair...

[@robinbywater679]

The

[@larryfardy1956]

Great video. I have an Onkyo HT-R570. I checked all the r22k dual resistors for continuity while on board and found 1 dead. I checked them by using the outer posts of the dual resistors for continuity since if 1 side was bad it would not beep. No need to check both with the middle post. I pulled it out and checked again to verify it was bad and it was. I also did the same for the audio power amps high current switching and found 2 that beeped because they are shorted. If anyone had questions as to my steps feel free to respond to this post. Thanks again.

[@GenerationXT]

Looks good but a couple of points, never use the old heat sink compound. Start with a clean surface. You can use a small plastic scraper to remove the bulk then get the rest with some alcohol. Something that will help your de-soldering is to apply some flux. Something like kester 186 is good. It can be had in a dispenser pen so as not to buy large quantities. Applying extra solder to the joint can help, but it still burns up most of the flux. Also make sure to clean up the flux left over...

[@dricklorenz9340]

My Onkyo HT-R570 receiver popped a few weeks back and went into protect mode (flashing red power light only, no display). I stumbled upon Kev's video, did the same troubleshooting using my Fluke multimeter and, based on the results, I decided to order a transistor set and 5W noble resistor in order to attempt the repair. Well, i was floored when the receiver came back to life after the repair! Although I'm a DIYer who has worked on cars and home repairs for much of my life, it took Kev's guidance to help me through my first real electronics repair, not the normal, simple swapping out of pieces and parts but actually changing out electronics components on a PCB! Kev, now I can help pitch in to reduce electronic waste from our landfills. Now where do I send the repair fee?

[@The_Active_Region]

Great job! I am glad it worked out for you. Another device saved from the landfill.

[@davidroque9841]

my speaker wires was touching and something pop then it smoked

[@Landotter1]

Your solder looked ok but I would have cleaned all of the manufacturers solder and resoldered them. Just saves you the trouble later.... Since you already had it open and disassembled, right there. Don't be afraid to reflow any questionable joints. You'll be glad you did! Good to see that you cleaned up with alcohol or acetone... Good repair man...

[@jasoneyes01]

Nice job. Always love watching amplifier repairs.

[@1c0n0fs1n]

Nice video. Found it because I have "Check SP wire" message on my Onkyo HT-R990. Two days ago, while watching Fury Road, suddenly the receiver shuts itself down. Trying to turning on again, it displays the damn "Check SP wire" for a fraction of a second and then shut itself down again. I had already replaced the capacitors on the HDMI board some months ago, and now this. Infortunately, even by following this video, all my noble resistor seems OK (still attached to the board they all indicates 0.6 when measured) and the transistor on the heatsink have been replaced by some Sanyo IC STK443-530 and two STK442-730. Dunno what to do except avoindg Onkyo products in the future, because I have found tons and tons of people with the same , unsolved problem.

[@DanielFreeman1]

Great video. I had used this to fix my HT R570. Same transistors and noble resistor went bad. Thanks.

[@mdzacharias]

That was a really good job though. Lots of guys' knees turn to jelly with this stuff. Keep it up and stay in touch if you need any info on Denon, Marantz Yamaha receivers, maybe I can help.

[@tonym.9930]

Excellent video and explanation with the ohm meter. I just had a channel blow on my Integra when I put a drywall screw through a wire in the wall. Looked this up, looked in the stereo and there was the charred transistor. Hopefully I can fix it but even if I have to bring it to Pinnacle at least I know what's wrong and I won't get snowed.

[@niwatuwayasaratne6246]

A Very good repair

[@eduugr]

That was fun, thanks!

[@jdn3744]

Thanks for the advice. I'm just a hobbiest with some successes with electronic repairs. I picked this receiver up on ebay for $45 as is including shipping so I figured ,what the heck. Nothing ventured nothing gained. Anyway after closer examination I could see no bulging caps but the 2SA1930-2SC5171 power transisters are showing overheating on the board from one end to the other of the board on all 7 pairs. Think I'll replace them and go from there.Thanks for you help.

[@1959Berre]

Put the desoldering gun upright at 90° to the board, so it will suck all the solder at once. Give it sufficient time to melt the solder pad completely.

[@jasoneyes01]

Mark or Kev, Seeing you troubleshoot/repair an Onkyo M504, M508, Sansui B2101....would be awesome!

[@The_Active_Region]

Just make sure you get all the metal debris out if you use a rotory tool. you may be able to use a sheet metal sheer but its going to be ulgy no matter what. If you got nothing to lose I would try to disassemble it piece by piece and take pictures or a video of the disassembly. and take note and mark connectors and cables where they went,

[@The_Active_Region]

Sometimes there is an access panel on the bottom of the receiver. if not you have to disassemble the whole unit to remove the main board. No way around it.

[@mdzacharias]

Been years since I've seen a 2101. On the Onkyo's, if an amp channel isn't blown, it's usually the 2SK389 FET's in the front end causing an offset. Very difficult for access, though...

[@charlestaylor9499]

To bad there's not more of you repair guys around, my Integra av receiver went out, now i am looking at spending 600 to 3000 dollars. Sucks, Maybe its time to upgrade anyways. Charles Taylor out.

[@The_Active_Region]

I would think there is a problem on the amp board you pulled out, test the components for shorts and the resistors for open continuity like in the video. and also look for burst or bulged capacitors

[@rodolfogomez382]

Thanks for your answer, but there is something wrong in the measured resistance, the fluke 116 multimeter terminals in ohms position gives a reading of 0.1, not 1 ohm.

[@The_Active_Region]

No problem. But if the amp going into protect there will be a problem or short somewhere compare your readings to other outputs

[@magichat1053]

Diagnoses Round 1 I used a multimeter to find the 2 shorted transistors and the matching dual resistor. Like kev31779 did in his video, I clipped the leads on the 2 bad transistors prior to ordering my parts. After clipping the leads, the unit was able to power on and stay on without automatically going into the protected standby mode like it was before. Ordered my parts from mouser.com (links at the bottom) Repair I was able to replace 2 "shorted" transistors (A1962 & C5242) and 1 "opened up" dual resistor. I ended up using 2 single resistors and soldering/bridging the middle prongs together for the middle hole. While I had the receiver apart, I went ahead and replaced the 5 bad 100uf caps on the HDMI board as well. Testing First bootup with everything plugged back in, I blow 2 10a/125w fast blow glass fuses next to the power supply attached to the main board. Buy a package of replacement fuses same rating from mouser to try again after re-seating all ribbons, connectors, and shaking the unit upside down in case any clipped leads or metal were shorting the board out somewhere (nothing came out). Put 2 new fuses in tried again, both fuses blow again. Disconnected the antenna/coax board, HDMI board, and ipod/iphone dock board, put in 2 more new fuses to test - same results - both fuses blow again after about 2 seconds of the unit being turned on. Attempted to disconnect the other board where all speaker wires attach to (the board with the 5 G5PA-28-MC DC24 relays attached to it) but with this disconnected I no longer get the red standby light on the receiver to come up nor does it powerup when turned on. Diagnoses Round 2 Used multimeter to test the leads on the underside of this "relay board" to check the readouts of these 5 relays. 2 out of the 5 were measuring in the 500's while the other 3 were steady at ~1ohm. My Question to the more knowledgeable electronics people out there...... Seeing as though the unit will not power on with this relay board disconnected, this would then mean that the current flow of power goes from the power supply to this board and THEN to the main board where those fuses are located. Is it possible these 2 relays are bad and thus causing some sort of power surge which is blowing these fuses or is it more likely that the actual power supply is bad??? Mouser has these relays for $3.50 apiece, just not sure if I want to keep at this and try this one last thing before calling it quits. Parts Used A1962 - Transistor www.mouser.com/ProductDetail/Toshiba/2SA1962-OQ/?qs=sGAEpiMZZMshyDBzk1%2fWi39v8mPI4jPHIOVN8C5K9gE%3d C5242 - Transistor www.mouser.com/ProductDetail/Toshiba/2SC5242-OQ/?qs=sGAEpiMZZMshyDBzk1%2fWi39v8mPI4jPHoIMIqujz2qg%3d .22ohm, 5w Resistors www.mouser.com/ProductDetail/KOA-Speer/BPR58CR22J/?qs=%2fha2pyFaduiHbb7zzJ6cb2el9G%252bgwVRdHFTcZBFBJdjgVGcjXZFCyQ%3d%3d 10a/125w Fast Blow Fuses www.mouser.com/ProductDetail/Eaton/BK1-GMA-10-R/?qs=%2fha2pyFadujmM0Q8l%2fgOi%252b4YzR5Ibqb2fAtF6nhzU%2fIQdKJLaUFapQ%3d%3d 10a/24v Relays www.mouser.com/ProductDetail/Omron-Electronics/G5PA-28-MC-DC24/?qs=sGAEpiMZZMtSzCF3XBhmW6rmK3VUQy7ZulImHcGuIxw%3d

[@Brian_C_6436]

***** Hey, any luck? I have the exact same problem you have (or did).

[@themostaveragegamer8512]

Hi Kev. Great video. I've got a similar problem with my amp going into standby mode. I've tested all the transistors and resistors that you did in the video but there fine. I know it's he right channel as that's the one that was making a crackling sound and I left it as it went away and then pop into standby. There is a board next to the transistors which has the channels written on it. It's the green board behind your hand. If I pull that board the amp turns on. Could it be something to do with the resistors or transistors on the right channel on that board. Also how would I go about clipping out the power to that right channel so I can get the amp working again for the mean time. I also have the service manual if that helps. Any reply would be great full thanks chi

[@mdzacharias]

The .22 ohm was a casualty, not a causation. Nice job but I've worked on a number of these; there is a small transistor between the drivers that goes bad, a small 100 ohm resistor next to them goes bad, a small resistor to the base of an output usually goes. Contact me if you need help.

[@ktos8468]

I can't buy transistor names 2SC1740S-S between the drivers. What is the replacement for this transistor or where can i buy it?

[@optics4062]

Great video. My onkyo txnr1010 receiver makes a loud static popping noise from the right channel only. Once it warms up it stops and sounds fine. Any idea what would be going out? I love this receiver and would like to fix it myself. Thanks

[@jimholloman4457]

How did you manage to disassemble the unit enough to get the bottom of the circuit board? How many screws did you remove? I have a TX-R820THX with a similar layout and I have yet to figure out how to get to the bottom of the circuit board (that has the 0.22 resister and the ouput power transistors). And, I have an 'Exploded View'

[@pvanb2]

kev, get some alligator clips hook up to mater, then turn camera on...

[@jgarmer]

The bomb thanks got me going again.

[@JamesCutlervk2tim]

Nice multimeter, I have one of those and it is excellent.

[@buonafede1]

Is it possible to just clip out the transistors from the heat sink and solder the new ones in place. Could save on some dismantling.

[@praestant8]

Buonafede No. You’d have to clip the leads of the transistor package and then try to get under it to solder. It would be a mess. When it comes to electronics work it should always be clean and proper with surgeon like precision.

[@jimholloman4457]

Would need to do the same for the resistor.

[@thajubb1]

Great video..informative,,, thanks sir...

[@izzzzzz6]

Hi there. Any ideas where I should look in an Onkyo TX-DS 696? It powers up and goes straight into protect. Thanks.

[@ThatGuyKappa]

love the desolder gun woo hooo

[@nickfatsis9607]

Just a suggestion, if you're having camera focus issues, you need to isolate the subject, like when you tried to focus on the resistor, the camera was focusing on your keyboard. a black background and some light on the subject will fix that, or when you tried to focus on the model number, the face of the amp was too dark and you had objects in the background, splash some light on the subject, this will fix most focusing issues.

[@PS4PROGAMER5456]

Bro camera is old

[@Faddablack]

was able to troubleshoot and fix an old hitachi amp which was outputing dc on the speaker output, being an old unit it did not contain a protection circuit. Thanks for the pointers on what to check.

[@Faddablack]

+land otter1 the amp belongs to a friend of mine, I did check the drivers and they seemed ok though I never did check the op amp. As far as restoration goes, I don't think he cares for it that much, it's an old unit from the 70s, and I noticed it had had some diodes changed in the past, on the rectifier circuit. Thanks for the info. Much appreciated.

[@regulobarajas7162]

Learned and enjoyed from viewing your video. I had the same issue with my Onkyo TX-8522, replaced output transistor and resistor and does not go on standby any longer. I do have another issue now on the channel I repaired, the sound is a bit distorted and the other channel works fine. I switched speakers and got the same results, could you please advise what may be causing this, I would appreciate your assistance and thanks for this video for those of us that need help from people like yourself!

[@42guitars]

have a onkyo nr 757 has a blown side what is blown it happened when it was on and I touched the the speaker wire on the back of amp then smoke cake out of it

[@steveboyd314]

How does one "clip the transistor out of circuit" please. Thanks for a very well done educational video.

[@ssadeghin]

I have the same question.... I just want to use as a preamp

[@mest1589]

My onkyo powers up gets video on all ch but NO Sound at all. One transistor on a ch blew/cracked c4468 everything else tests good. I noticed all white resistors read .17 ohm instead of the .22ohm.

[@jasoneyes01]

Kev, you might want to check On Semi's website for substitute output devices. Just enter the Sanken number such as 2SA1386. Have heard nothing but good thing about their quality. They are the apparent manufacturer for Motorola I believe.

[@duaneslemko2]

I have an ONKYO TX-NR708 Receiver that had the HDMI board replaced and now it went crazy again. I just had optical plugged into it to stabilize it, but it finally went black screen now with a constant clicking noise. Don't want to recycle, just want to fix it. Thanks, Duane

[@abelabner]

TY Kevin for the video, I have an Integra TDR 7.7 And it appears the sound channel transistors attached to the heatsink failed. The noble resistors seem fine. It still doesnt get out of protect mode. Where would you or any viewers go next?

[@thersten]

Thank you so much! I found a burned resistor & 2 faulty transistors thanks to your video. I removed them and brought my Onkyo receiver back to life minus the left speaker channel. I'm waiting for replacement parts now, but does anyone have any idea why this failure occurred? Should I get different manufacturer parts or could it be a cooling fan failure?

[@user-wh4uv2xk3p]

I have a TX606 that has this issue. Would really like it up and running as it was the secondary reciever for my gaming setup. Would you be able to fix it

[@tej262]

Bro teac 8800 av receiver only front lift right chanels not sound bro centre back sorrounding is good work but problem plz reply me

[@The_Active_Region]

I will check that out thanks..

[@nevetsreyd4688]

Nice fist close ups

[@anthony2010707]

very informative video, i have a Marantz nr1602, there is a problem with the sound, some of the surround modes seems to be acting up, mainly losing audio from the centre channel, as well as a strange noise in the audio as well, any ideas as i was wondering whether the filter capacitors were getting bad.

[@shaunmills4611]

I have an Onkyo HT-RC160 and something odd happened recently. My right rear speakers volume output is a lot weaker compared to the left. My receiver just switched off one day. When I calibrate it does not set it according to proper distance which is same as the left. I have switched over speakers and wires and same thing so it has to be the channel itself. Calibration raises the level to try to match the left but the left is still louder. I also ran fingers across tweetere to check air flow and it all looks good. Very confused.

[@donnieanderson7950]

What part did you clip so u coukd use it until new parts came in? How do u do that?

[@jmkcornel]

will also be working on my onkyo r560. just waiting on the outputs unfortunately it also took the drivers out. saw some pots on the board. did you bias yours? can't find bias info

[@coondogtheman]

I have one of these but it's the SR505 and it started smoking and sound was cutting out. Saved it from going to the dump. Haven't opened it up yet. Are these output transistors a common failure on these? Would it be that easy to change the bad ones out and have this set work again.

[@phillipdonovan3157]

This video was excellent even a beginner would be able to follow along. I just wish I had confidence in soldering, still a beginner my luck I would wreak further havoc on my Onkyo than Ive already done by stupidly bridgeing the Rear Speakers to the B Channel thinking Id be able to swap between for boosted volume when listening to music, and 5.1 Effect for movies. Learned alot from this video great job, But still not touching anything i dont know about haha, Off to repair shop I go I suppose, How much do you think they would charge for my situation?

[@fratiee]

Thanks for video !

[@sokoloft3]

I have a TX-DS494. As of the past year or so its right channel on output A sometimes works. As of yesterday it wouldn't output at all. If I turn up the volume it would sort of crackle, thats it. That has been happening for a while but it'd normally come out of it and work. Any suggestions? Thanks. I switched to channel B for now. However I don't have as much functionality on A and it does sound slightly different. I'm going to try channel A again tomorrow and see if it'll come out of it. However I'd really like to fix it.

[@jensmarr3162]

Hi, i have the same model and its looks like i have the same prob. Can you explain what the receiver was doing when you press the standby button. My its wakes up and after 1-2 sek its going back in standby and the red light is flashing. Thanks.

[@7ngaf]

very good video thanks

[@dble0seven]

I just acquired an Onkyo 606 that is exhibiting the same issues. I'm curious if you could give me some pointers to troubleshooting to figure out what is wrong. I am currently getting some mixed results metering the parts you discussed in this video. I would greatly appreciate the help. thank you.

[@garybeckham8055]

I have a Onkyo HT-R560 Receiver doing the same thing ... i haven't used it in almost two years and i took it to electricians and they couldn't fix it because they couldn't get the parts for it that is so crazy to me... i just want to send it somewhere and get it fixed i called Onkyo myself and they wouldn't even help me with my problem .. i can buy a new one for what it would cost me to ship it to MI.. to their guy they use to fix all their crap.. so i called him 75$ to just open it up.. take the top off.. and he didn't tell me how much an hour after that so i figure it would all come to around 300$ or more to fix it going threw Onkyo... Heck i can go buy a newer one alot better than mine for that much money so why would i want to fix mine if im going to have to spend that much money..idk.. I do know i wouldnt recomend Onkyo to anyone that was in the market for a receiver!!

[@bautistaconcon5719]

I have also the same problem about my amplifier, its big help for me that I see your video, may be you have some more videos to upload,thank you and God bless.

[@FATBOY1340]

very usefull video.

[@The_Active_Region]

Same here .. Thanks

[@berglerlemur]

I was afraid of that. I'm seriously considering using a nibbler or a dremmel to make my own access panel...

[@The_Active_Region]

it was lucky thats all that was wronge with it. From what i know it is in service right now. Thanks for the comment ive watched a few vids of yours before. i aslo was a tv vcr repair tech about 13 years ago

[@NelsonBigGunP200Fan]

so question. If you test audio output transistors with a meter, and you can test them both ways. that means they are dead right? I heard they only test one way.

[@GenerationXT]

Yes, there are other devices which can sub the originals just fine, without using NTE. They will be better quality and cheaper to boot.

[@Synthematix]

onkyo are pretty decent im treating myself to an onkyo CR-N755

[@master9716]

Where are you located I need my Pioneer Elite fixed. Heard a loud POP and then the protection light came on wont turn on anymore, I tried the little trick where you hold down 2 buttons it came back on for a couple seconds then the protection light comes on again .

[@anthonygibbs5624]

Hi and thanks for the Vid, I have a similar fault with a NR609 that was dropped, i have tested and there are shorts on one of the C5242 and A1962 transistor sets, but the resistors appear to test okay, is it possible for the transistors to go faulty but the resistors to remain okay, p.s there was a crackle and a pop and a burning smell when trying to get off standby initially, any info would be greatly appreciated...cheers

[@joeh.6262]

what a pain to get to and replace. I ended up trashing the thing.

[@madman216fpv]

Hello. I have a peculiar problem with my Onkyo TX-NR515. Everything seems to work, except for a single output channel, the front right. Now, I get no protect mode issue at all, in fact I even tried to heat gun the dts chip, and installed a fan and heatsink for it just in case. HDMI video and menu comes up on screen fine. All audio out works...except for that one channel. I tried testing the emitters, and they seem to check out fine all across...(no protect, of course). All the NPN and PNP's seem to check out fine, but of course they are still in-circuit. On that model, it looks like the drivers are on a seperate board. There is not static or other noise...clean sound all around except for the front right...strange...Thank you for any suggestions.

[@jdn3744]

I have the Onkyo TX-SR607 that goes into protect mode within a few seconds of turning it on. If I remove the Driver Amp. PC Board it stays on. Would that indicate there is a component failure there? Removing the HDMI board makes no difference. Also would this rule out a power supply problem ?

[@lacey397]

nice job...

[@justinberry3991]

Sweet compound? What's the name of the stuff you put between that one part and the other part? The white plastic tube with white goo? I wish you were my neighbor. I shorted one of my only two out of five. You'd be my favorite neighbor. I loath circuitry lol

[@justinberry3991]

I found it. Heat compound

[@jesuswong7154]

HI Kev. I have an ONKYO HT-R420. The computer was lightning-free and shut down and not working. The relay is not activated and probe the transistors C5242 are not shorted and the resistances of .22 kohm are well. Which component may be damaged?

[@familytimes6031]

Hello great job with the repair. I have a question... I have an Onkyo TX-NR535 that has stopped working. Recently I had to turn off my breakers repeatedly while installing a smart light switch. Since then my receiver has been making a clicking sound and won't power on. The sound is coming from the Power/Stanby button. Any suggestions as to what the issue might be?

[@The_Active_Region]

I usualy do all that in most my other videos but i was just a bit lazy on the details in this vid.

[@vinha916]

I have kenwood AR 304. It turn on and work only Speaker channel B. Channel A is silent. what do you recommend I should check?

[@aharami]

I have a Onkyo TX-SR876. The fornt left channel doesn't work. Receiver turns on and works ok,except that one channel. Made sure its not the wire or the speaker. Do you think it could be a similar problem?

[@davidst489]

I have the same problem on my TX NR-509. It comes on click....shuts off click. I was playing around with some new speakers and I guess the wires touched. Now I would think the protection circuit would do it's job but noooooo! Anyway where do you go to for these parts?

[@mikeunivers]

How do you check the BIAS?

[@markprince3341]

Hi, great video. I have an Onkyo TX-SR576 that was working well but now started turning itself off after a few seconds and standby light blinking. I have tried clearing the memory, unplugging everything, and leaving it unplugged from power for hours, but its still in protection mode. When I opened the case I noticed a large blob of black tar like material on the PCB right next to the large capacitors, and a smaller on on the board below that one next to a smaller cap. If that stuff has leaked from those capacitors would that cause the same result (as in protection mode activating) as in your video? and can i just try to find parts and replace these to fix it, or should I be testing the transistors and resistors that you replaced?. It cost me nothing, it was a rubbish dump find that someone had cut the power cord off. I took it home and wired a new power cord and it had been working perfectly for last 6 months. I really like this unit and would be keen to fix it again if it costs a few dollars for parts and a bit of time fiddling around, but not willing to pay someone hundreds to fix. I do have a little experience with soldering, building kits and other things but have never really fixed stuff before. Also, will i have to drain voltage from the old cap before playing around with it? Any help or advice appreciated. Thanks

[@The_Active_Region]

I cant tell you if the capacitors are the only problem but it is a good place to start. Yes drain the capacitors. Some will drain by themselves with bleeding resistors in the circuit some will not. Check with multi meter. If caps are charged after being unplugged for a min then use a bleeding resistor. If caps are not the issue well it is a bit more in depth of a repair.

[@Luke-12V]

Hello, when the transistor is changed to the same one, it is necessary to set the block current, or in what case to adjust it, thanks for the possible explanation

[@The_Active_Region]

Sometimes there is no bias adjustment. If you put the correct part in it, it should be good to go.

[@Luke-12V]

Thanx

[@lezbriddon]

What I dont understand is this is supposed to a 7.1 amplifier, or... a 7 amplified 1 (sub) phono out amp. but surely for 7 amplified channels you would need 7 pairs of output transistors, and these only have 6.....

[@JonathanDKearney]

Those massive caps are kind of scary to be poking around near. Did you discharge the caps before doing this work? If so, how? If not, how do work around them?

[@The_Active_Region]

I don't remember what I did It was so long ago. But the procedure would be is to check them with a meter and if they still have a charge you can use a resistor like a 10k may be a good place to start but will drain slow. If you go down it resistance the resistor will be hotter because the cap is trying to discharge faster causing more current across the resistor. Never touch the resistor as you hook it up, use a set of clip leads. I wouldn't try to work around them charged unless you have a reason to.

[@calarco68]

Thank you!! GREAT VIDEO. I did the repair. Now my tape output and my MD tape output are not working. Did i forget a step or is that a whole separate issue. THANKS AGAIN

[@The_Active_Region]

+cc cally Sounds like you may have other issues or may have caused another. or a cable had become disconnected,

[@calarco68]

+kev31779 thank you. I'll probe around.

[@The_Active_Region]

I am sorry I dont do internet repairs These videos I make are a just guide or demonstrations for diy. But it sounds like you blew a final amplifier or capacitor.

[@bautistaconcon5719]

Thank you for your reply, I apprisate your kindness.

[@DaCamoGrower872002]

Which one is the sub woofer channel on the htr 560? I don't have a voltage meter and if I just remove it til I get the parts will my system work

[@galindofelix8585]

Hi, I have the same receiver, turns on fine but no audio, I measured the .22 ohms resistor and all of them were good is there something else i can check for?

[@purplehaze6t9]

hello, I have the same ONKYO TX-SR502 RECEIVER but when I turn the power on it shuts off right away I'm wondering if its the same problem as yours. the caps all look really good no bulging or leakage one good sign is the fuses are not blowing I have not got into it and tested anything yet I thought I would get some advise as where to start. I repair CB radios so I am very familiar with a lot of these parts, and what they do you think I should start testing the outputs first, and take it from there I noticed you left your in the board so I don't have to remove them. if you can give me a few pointers I would be very grateful. thank you. "god bless" ben..

[@Kennynva]

There is a 2SD1047 right, that replaces it the B817?