I'm always amazed at how long you leave a device switched on despite a short circuit. OK, currents and voltages are lower when a light bulb is connected in between, but a short circuit is a short circuit.

I picked mine up 20 years ago at a yard sale for 20 bucks, I recapped it this winter, I found a service manual from an old technician that had a service bulletin for that hot transistor problem, if you send me an email address or post office box I’ll send you a copy of two ways they fix this problem, it involves relocating it, pretty easy to do, keep up them videos 👍🏼

Excellent job on a beautiful amp! Thank you for showing your thoughtful procedure.

Another gem Joe. Gold standard for audio equipment repair channels as far as I'm concerned. Camera work is excellent. Zooming in on the exact test points for various components is so appreciated. Most other repair videos put you in the ballpark, but you can never quite see what they are doing. You are so good at explaining everything as you go. Very helpful for someone like me that's trying to learn this stuff as I own quite a bit of vintage HiFi equipment. Look forward to the next tutorial! I wish you were located in my area.

Nice to see discreet transistors for the outputs instead of those dam darlington packs.

Nice video. i must adjust my Bias on my Marantz 2238B after that i replaced all old capacitors. i see that its necessary after all years

Thank you for your time, you straightened out a very god receiver for another run at life.

When you don't have the exact replacement part, you should swap the other transistor too, even if it's good. These guys work better with their respective complementary transistors.(MJE15030 and MJE15031 in your case)

Thank you great vid, love them old pioneers.

I've seen this on a couple of your videos. You can and should also check emitter to collector on those outputs. The diode check will just show zero if shorted or open if good, probably give a continuous tone on a short, though I'm not sure about that on your meter. I've seen E-B and B-C junctions appear to test fine and still be shorted E-C.

Joe that Pony tshirt brings me memories from the 80's....

Great work again Joe....I'm awarding you the Pioneer SX-Series Award for this month...lol

You get to work on some beautiful units , this one especially. Hope you’re well, keep it up.

I usually add additional self adhesive heat sinks available on Amazon.

excellent troubleshooting Joe. the experts on Audio Karma recommend beefing up the heat sinks on the regulator transistors on the 780 for the same reason you have on the one thats extra hot. a very common problem it seems.

Nice job on this! I've got one as well and it's a nice unit with lots of power. Love the black meters on this series, though I do feel the x2x-x5x sound a bit warmer. Still, no complaints!

Really I love to see your videos olways I learn something. So professional work god bless you

Muchas GRACIAS 👌☺️

hi Joe, I like your vids it would be helpful to show on the schematic what you test and why, And what is the logic behind it... so that way all the green-horns like me could understand what you do and why... without explaining on the schematic what you do only the "experts" understand your explanations... And those don't need to listen to videos about how to fix amps...

Hi! Tomorrow i have a plan to do the adjustment and also make a note too you 👍

Merci for this video. Very well explain!

I may have missed it, but did you check the same transistor in the other channel as a reference with your temp checker? Also, maybe check after bias adjustment to see if still hot? A screenshot of this transistor as shown in schematic would help those of us not familiar, just a suggestion for future vids. Cheers!

I'd really like if you explain what and why you're doing while you're doing it. That would educate us a lot. Now I hardly understand what is going on.

Beautiful work, but then again, I’m biased because I have the same receiver.

easy amp to fix this one

Nice job Joe ! I'd like to have seen the bias tested after adjusting t eliminate the dc. Just wondering how much it affected. great receiver there I love that series.

❤❤❤🎉

Just found your channel great repair those old amps from Pioneer are beasts and it has the same output transistors as my old HK 870, and I noticed you have pretty much the same magnifying glass on the arm as me :) can it also switch color temperatures? I had the little controller on the cord, but i replaced it with a 2ch rf dimmer unit, and I also 3d printed a new triangular bracket that is closest to the lamp part now I can hook up a small camera to the light. And I think you might have the same variac as me too it looks pretty much identical.

If you don't mind me asking... What source did you use to cross the old transistor to a Motorola MJ? Thanks

Great job, i would like to see someone work on MAC1900 receiver on you tube. My Mac's lef channel went up a little puff of smoke it had been running a little hot before it quit on me .

Hello Joe, Working on a sx-1500td given to me. Missing the power transistors and six others plus two were replaced with 1845's. I think they were in wrong. the emitter resistors were missing also. Blowing the fuses when I replaced everything. Did you say you powered the 880 up to test the emitters ? On the dim bulb tester? Thanks for your time brother.

Where can i get schematics of my sx880? Also love the turntable killer idea.

You should have changed the transistor itself .. and caps around it

how can the heatsink be hotter than the source of the heat , the transister ?

You know when heat sink has higher temp. than the transistor it's cooling there must be something really wrong with the lows of Physiks in this transistors sorounding space 🙂

We're are you located?

The heck is "RMP"? Don't you mean RMS?