You WILL NOT BELIEVE What The Tech Before Me Did To This PIONEER SX-737

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One of my favorite things is being the first person to work on a piece of vintage gear. Unfortunately, sometimes one of my least favorite things happens: gear shows up because of someone else's work! I really couldn't believe what I saw here and I'm so glad I was able to correct it and make it right for the owner of this Pioneer SX-737.

[@PioneerGuy581]

how long did it take you to get that board out to swap those transistors?? i bet loooonngggg time. i have a 737 in route - cant wait to dip into it - I am doing a 828 now - much harder then the SX-880 i just did, i have not done repairs in a long time, these old beasts are a challenge. I have been soldering for 40 years. Probelm when you get old is your eyes get bad - I have maginfiers and microscopes and i still cannot see.

[@Silent-Lucidity]

You're a good man! Keeping the community on the right track!! Nice work sir!

[@fredericraynal6664]

You've done a very good job, as usual. I've been following u for quite sometimes now. Especially for marantz stuffs, you gave me lots of tips for m'y marantz 2245 which i restored completely a couple of weeks ago. Carry on dude. By the way i'm from France, if whenever u need some advices or gears we use in France u are welcome.

[@williammitchell3271]

I'm sitting here listening to my Sansui thinking how close I came to giving up and replacing it. I could not find a qualified tech to do the service. Took it to a little shop in FL. Luckily the guy realized he was in over his head and gave the unit back without throwing junk into it, so all I lost was three weeks. Now I know better. Thanks for your work on this channel and help.

[@ChudGippity]

Can you please help me ??? I gave my luxman lv 103 to technician and I Got it back by force and mosfets all burned out plus many more burned parts that I don't know what are... Anyway can you please tell me where to get gets or how to mod it ??? I'm not from USA BTW so maybe you can send me a link of a solution ??? If not I will end up in jail for murder

[@spacemissing]

Someone screwing up a vintage receiver is a travesty not to be excused, but at least it can usually be restored by a "better" technician. Vintage watches that were once incredible timekeepers are sometimes irreversibly damaged by hack-artists. THAT is a crime which Should be punishable by years of unending, merciless torture.

[@wendellporter4875]

i have seen this alot, just lazy people that work on them, i repair these correctly

[@MrDoneboy]

As an old school tech, it thrills my heart to leave this art, in the hands of capable younger hands, like yourself!

[@davewallace8219]

the tech....couldn't repair a lawn mower!

[@waynewayne3709]

I've been a electronics tech for 30ys and seen some sorry full sights over this time. Some forget the basic fundamentals of logical fault finding. Great job there..

[@allenscamaro2816]

This is exactly why I haven't shipped my SX737 to get repaired yet. Not only do I not have a clue who to send it too, but I also have trust issues like this right here. Same thing with muscle cars, I build my own because of watching the industry rob people for decades.

[@geomorphdog]

To be fair, it is getting harder and harder to find transistors, especially matching npn-pnp pairs. Mouser just ran out of KSC1845's and might have them again in July. Digikey hasn't had them for a year or so. And now KSC1815's are out of stock in both places. Still no excuse for using the wrong transistors, but I could understand using salvaged transistors as long as they were good and correct. I'm having a hell of a time with my latest parts order.

[@PhuckHue2]

We're in the shortage plague. For those KSC's I get free samples from Onsemi

[@FRUITNERD]

Wow....... But not surprising, by no means am I defending the poor so-called technicians but a lot of times I have noticed that people get what they pay for. An actual qualified reputable person doesn't exactly work for free. We have all seen the marketplace and craigslist ads for "I can repair your vintage audio gear for $30" I give free estimates and have been told that they can get it done cheaper only to have them bring it back to me later after someone installed cheap Chinese capacitors that aren't even of the proper value. Good people there is a difference between a $1 capacitor and One for 5 cents.

[@Blowncapacitor84]

Woooowwww!!! Those are definitely out of a scrap parts bin for sure! Absolutely unacceptable!!! Heck of a way to add resistance to a resistor🤣🤣🤣 The KLH's sound great!!! Thank you!!!

[@reinkansman1081]

It is amazing the people and businesses that are collecting money as qualified customer service professionals and treat customers like this. Nice find Aidan. I appreciate your passion for doing the right thing.

[@drakefallentine8351]

Great job repairing this disaster. One big take away is when you find this type of poor workmanship, the "debris field" is usually localized to one area. These guys tend to get mired down on one point and focus all destructive activities there.

[@glenz1975]

I've seen this many times, muppet technicians creating havoc inside a lovely piece of equipment like this. Have serviced and restored a few of the models in this range. Currently doing an SX939 and last week fixed an SX434 that had been got at like this, the soldering was awful. You're doing some good work and keeping these great receiver's going. 😊

[@emiliobercial]

I've got a SX-737 and almost cried when I saw the mess that "technician" had done. And write "PNP" or whatever scratching the heat sink... no words. I would send him to jail :)

[@PhuckHue2]

He shouldn't work on any equipment. As a safeguard I always write N or P right above the transistor before I replace them all as a safeguard. When I'm done remove the letters with alcohol

[@karaDee2363]

Fortunately you know what you're doing and do a great job

[@wb8cxo]

Great Job! IDK why tech's feel it's necessary to use substitute parts. Doing it right (as u did) takes just a little more time than a botched repair and results in a happy customer! Thanks... 73, Mike

[@officialmikethompson]

Just did a Sansui G-3000 where someone put the outputs in the wrong places (NPN/PNP). Sucks when you have to tear more apart just to fix a screw-up.

[@TJET737]

Interesting video. You should make a video that list all known transistors that are troublesome in receivers of that era. I know you mention them every once in a while. Maybe AK has a comprehensive list. Thanks for all you do!

[@g.fortin3228]

I had watched this one before doing my 737 restore to my dad's.. as a primer. Nice job and I learned a few things. Still made a couple goofs although I was able to take my time, fix them and get it really right. Also watched your relamp vid. Nice stuff. keep this channel going it's quite interesting !!

[@Bob_C]

I'm a little late with this comment, but I just discovered your channel and subbed. I still have my Pioneer SX-770 Receiver that I purchased in Japan around 1971 while I was serving in the Navy. It still works fine after 50 plus years, but I realize that I should have the caps, transistors, etc., replaced, so it will last until I croak. I also still use the original Pioneer CS-66E 40 watt speakers that I bought with the receiver. They still sound great without any distortion. I hope I can find a qualified repair tech that I can trust to do the work correctly. I have tinkered with electronics and done quite a bit of soldering since I was a kid (back in ancient history lol), so I could probably do the work myself and save some money (and worry). Btw, I believe the reason my receiver still works is because I periodically blew the dust out of the unit and kept it in a fairly dry environment most of the time, with one exception when I had the receiver with me onboard ship for one cruise. I also never cranked up the volume past 50%. I don't know if that made a difference or not. I'm learning a lot from your channel. Thanks.

[@JamesE707]

Although inconvenient, sometimes it's worth isolating the main power amp and use a dual power supply to supply power to it, prior to that - attach some 50W 8-16ohm resistive loads to the speaker outputs. Then you can apply voltage sources incrementally and slowly and watch for incorrect current surges on either channel. Anyway, that's just me sounding off. ;o)

[@ryanfaris5106]

Although not as bad, my girlfriends dad just gave us an old pioneer sx1050 that he had been "restored" a few years ago from a very recommended local audio shop. I flashed a light into the chasis and saw original caps, so I opened it up and this shop literally only replaced 4 caps on the surge suppressor pcb and nothing else. He said he paid $500!!! The unit was unenjoyable at low volumes due to white noise. A recap removed 90% of hiss and now it's an amazing center piece in our home. At some point I'll go through and check the transistors but I didn't have any good replacements on hand, but really surprised what shops consider acceptable these days and the prices they charge for nothing.

[@JamesE707]

After seeing this, I know that you'll simply have to go through the whole circuit again! What's more, if the service manual is incorrect (and that happens), or there was a late substitution by Pioneer, then you've got your work cut out. While it is easy to mock someone's previous work, there are sometimes outstanding and idiotic individuals who do not know what they are doing, and by that I don't include those who realise they've made an educated error, no - I'm referring to those who should not be in that business.

[@relvintageelectro2425]

What is the voltage on base output pin ? Because i measure on that 0.49-0.50volts

[@dougbaker9473]

Where are you located ? I want my SX-1080 redone . Excellent videos 📹 !!!

[@jetsonIFY]

Very nice work!!

[@b.powell3480]

WD-40, maybe?!

[@relvintageelectro2425]

What number you replace those round transistor 1451

[@Zhorellski]

is it safe to plug Tube preamp Bluetooth (dc 12v) device on the back of this Amp?

[@johnny7254]

Just writing to say that your taste in music (jazz in particular) is superb. It's almost enough to make me forget that you once power-washed a receiver.

[@JamesE707]

Now that I've finally watched the whole thing through - well done, nice work there!!!

[@johncunningham5435]

What a hack job, one of the worst I have ever seen. Trouble is, there are to many bad repair shops out there, giving the rest of us a bad name.

[@tigerbalm666]

I has 737, and this looks so different from mine...my 737 sounds great after replacing with ceramic fuses...

[@FortyTwoAnswerToEverything]

I was forced to leave behind my 636 when I moved from central america. I miss it!!

[@davidbradford8542]

Story of my life a hour to fix the damage caused by some previous attempt and then 15 mins to fix the original fault. The ones that really get to me is when a customer swears blindly no one has been inside, those fuses must of wrapped themselves in kitchen foil lol.

[@dontcare563]

Good job but why didn't you do a good visual inspection inside before you powered it up with the Dim Bulb? I would think that would be pretty much standard operating procedure when working on anything this old.

[@canadavey]

I'm getting more and more "disaster repairs" that were done by "technicians" that were KZbin certified and found on Facebook Marketplace. I haven't see anything quite so bad as this yet, but this was ridiculous. Great work as usual. Sounds like you have a little head cold or something? Feel better soon bro.

[@davewallace8219]

I wonder if the bogus tech... sold the 2 ...good ..transistors out of the unit

[@zulumax1]

I have one of those basket case bodge jobs as a project now. Wish I could send you pictures of how it was when I got it. I was working on it for a local record shop that sells used hifi, it is a Sansui G-8700DB. Both channels were shorted T03 devices with only 1 transistor good out of 8. Original Toshiba's in the right channel and mix and match different branded wrong transistors in the left channel. They increased the bias resistor on that left channel just to make their bodged job function. Half a dozen resistors on the driver boards on both channels overheated so bad they are off value, and two of the 390 ohm ones got so hot it melted the solder on the circuit board and the lead fell out and opened the circuit. The 3.9 ohm soft start resistor is open. The driver transistors have had so much current running through them that even if they test good, they should probably be replaced. The owner of the shop I was working on this for said "keep it". (edit: changed bias transistor to bias resistor, was in error) If anyone out there buys a used old receiver, have it looked at by a competent service person before you start using it.

[@JCSoundr]

Man thats some nasty work, Good job cleaning that up. Yes definitely a good idea to replace all the old trimmer pots with multi turns👍

[@herbb8412]

It would be entertaining to watch you interview the guy who made this mess.

[@peterwikvist2433]

Good work in restoring that unit! Yes it is difficult to find reliable technicians.

[@doctorcircuit5338]

Where's the duct tape 🤔😨😜

[@williamcobb6322]

Outstanding work as always! Would have taken all the parts in a bag that we're bogus and the customer receipt to the shop that did the "fixin" and requested a refund! If no go on the refund, then a call to the state consumer protection bureau or better business bureau. Better yet, interview your customer that gave you the unit to repair on your channel and have them identify the shop of horrors.

[@alexkay1874]

Good KZbin Drama But your Childlike Overreaction was a bit much

[@danmackintosh6325]

People, we have found the original "tech" lol (joking of course, but I do think the reaction was justified. If this was an owner-attempted fix its one thing but when somebody pays money for a professional repair and gets back something like this....

[@alexkay1874]

@@danmackintosh6325 Your statement is Nonsense

[@danmackintosh6325]

@@alexkay1874 I'm glad you believe as Much. Shows all the more likely that you were in fact somehow involved in the butchery of this set...

[@alexkay1874]

@@danmackintosh6325 Your Silly And your statement is more Nonsense

[@TrevorsBench]

The shop isn't stocked for repairing these old stereos. Lazy substitutions and a 'good enough' attitude. Not very good work, they were hoping to get it out the door before something else blew in the amp

[@stereovintage770]

Your genius bro! keep up the good work👍👍👍

[@larryshaver3568]

that technician didn't know what he was doing

[@theaveragesimmer4780]

I cant imagine what would make him want to replace the transistors in the first place, let alone not even replace them with the same kind.

[@insolentstickleback3266]

Customer sends up “Bat Signal,” AHfixit responds, saves the day! 💥👍🏻

[@ericschleppegrell4467]

Yeah someone had NO clue what they were doing other than replacing parts with similar looking parts. I'm surprised they were actually soldered and not hot-glued.

[@tomstrum6259]

Yeahhh.....There's some vintage equipment Butchers out there !!! .....Those Asian oem hi-gain, driver-output semi's have always been difficult to replace correctly.....When your Pioneer is Burning a quart every 100 hrs,.....something wacked there ! Thx for sharing..

[@davewallace8219]

good work! by you! thank you!

[@robertdavis5714]

This has been my Life with a Kenwood 9000G and power transistors, at least the last idiot (asked him to do 4 hour burn-in and claimed not required and 90 minutes later SPARKS) refunded my money. But, my search continues to find someone that can replace my power transistors and that will function longer than 90 minutes.

[@ReyciclismoMTB]

My fisher 2015, is a bigger disaster no way to figure out what was someone thinking or planning. I saw a bit of smoke in mine as well, a cooked resistor. Been collecting parts for the future restoration. Can’t find the broken eq slider board.

[@jessepaul9774]

Wish I knew your location. I have a pioneer sx 680 that needs to be fixed. All I know is the left channel quit working and it blew the woofer driver in my left speaker.

[@joerico9461]

I don't know anything about the repairs that you do best I could do is get the dash lights working on a old Buick. But I do have a old Fisher receiver from 77 if I ever have trouble with it I know who to call . You do awesome work my friend ✌

[@Mrsteve4761]

Well done. I dare to say it's despicable that it should be returned to the owner in that condition (no less having taken money for it!). And to think this technician is "still-at-large" wreaking havoc on audio equipment of other unsuspecting owners. SMH.

[@DoNaSbaR]

8:10 maybe... PNP ???

[@davewilliams5932]

Hi AH-FIX-IT, do the transistors on the power supply board get hot when the unit is working properly?.

[@AHFixIt]

Certain transistors on certain receivers will get quite hot to the touch under normal conditions.

[@davewilliams5932]

@@AHFixIt ok thanks, but these are the ones on the pioneer sx-737 power supply board.

[@davewilliams5932]

Even though I change the transistors on the power amplifier board, there is still popping and static on the right channel.

[@marka1986]

Would have thought that the previous tech would have bench tested and realized that their repair wasn't going to make it.

[@ahmadalawadhi538]

you are professional reper person god bless you. I olways respect people who know thim work

[@chadfrench955]

Are you still local to KC I’d like to pick your brain.

[@ericschleppegrell4467]

Cab you please share the part number on the bournes pot you used? I've never had to replace a VR that I didn't have a NOS one in stock but I'd love to start using those. Thx!

[@AHFixIt]

3386F-1-101LF

[@tylerjezowski5633]

Transistor, I thought you said RESIStor

[@greatreset3]

I wonder if that's not oil, but lighter fluid all over it?? Amazed it didn't blow the transformer!

[@danmackintosh6325]

Wouldn't be surprised if that's what the monkey "soldered" with tbh looking at those joints... wow.

[@chipsarver6994]

Great video- great save - fun to watch

[@erichimes3062]

Dooooooooood.

[@Frank_nwobhm]

Nice work. Now if we could just teach you left from right we'll be cookin' with gas. LOL. I'm kidding of course. This is all way above my pay grade but I admire your work and thoroughly enjoy your presentations.