Pioneer SX-950 Repair

Back after a long absence! This video shows the steps taken to fix a Pioneer receiver stuck in protection mode.

[@DavidOMart]

He’s back!! Really missed your videos. Thank you for taking the time to put this together Ray.

[@scossa_vr]

Welcome back Ray, finally see you again.

[@valperiandri6055]

Glad you're back!!

[@diogenescaruaru]

Nice tip about the Ten Worst Transistors list. Glad to hear from you again.

[@raygianelli3612]

It's a great resource. I'm sure as time goes by there will be more to add.

[@knifeswitch5973]

Welcome back Ray. Every 1318 I come across goes byebye. Good to see you again and thanks as always.

[@scrappy7571]

Hi Ray! Glad your back. I have replaced many of the 1313 in my Sansui's. Some were so bad, that tapping on them was inducing noise in the output.

[@capriracer351]

I have an SX-5570, which is the black faced version of the SX-950. In the 6 years I've had it, I have had to go in and make repairs about every 6 to 8 months. While I am no advocate of shotgunning components, I finally did that this past spring. It was just a cascading chain of different failures over and over again otherwise. Part of the problem may be the fact that this unit was in a shed for the past 15 years before I acquired it, so it would have gone through extreme heating and cooling cycles here in Pennsylvania. It could be as cold as 10 to 20 degrees below zero in the winter at times and as warm as 100 degrees in the summer on occasion. It is running much cooler and the sound is very good now that I "shotgunned" it. There are many transistors in these that are on the naughty list. I replaced almost all of them. Did not do the pass transistor and it's opposite polarity equivalent in the power supply that you replaced in this video though. My voltages were still spot on through the entire power supply. Hopefully it will be many more years before I have to repair this again.

[@Traci_S_Aaron]

Hi there again, it's good to see you.

[@mdzacharias]

Glad to see you back! For future reference, the 150 Ohm resistor in series with that 1318 is also a common failure, and the blue (sometimes white) Sanyo coupling caps are notorious. In the SX-828 they cause big problems in the tone circuit but I think on the 850 they used Elna for that.

[@josephlalock8378]

always nice to see a video from you ray. glad to see you back. i found an updated kos (kill on site) list awhile back. about 50 transistors are on it. i do not have a link but it's on ak somewhere.

[@g.fortin3228]

Another awesome one, Ray :- ) I'm sure this will be helpful in the future when i have one of mine act up or am checking out something for someone.. the little bits of info are super valuable to us fairly new to troubleshooting. I'm happy things are well with you and you are back. Rock on dude ! I have some light hum in my Nikko NR-1415 that needs to be addressed at some point (probably over the cold season when i'm indoors more!) and all these little bits of info help!

[@Edisson.]

Hi Ray, very nice to see you again, nice work congrats on the win over the machine 👍. It happened to me that I forgot to measure a part of the circuit, but if you measure everything, you also write down the values ​​and during the testing, the source will lose 7V and you will only find out when the parts burn, which is annoying. That's why I made this multi-channel voltmeter and I constantly monitor all voltages during testing. Thanks for the link 🙂 to the list of problem transistors, I was just looking for them, I have one problem amp on my desk right now with a random glitch in one channel. Nice day 🙂 Tom

[@stirlingschmidt6325]

Thanks Ray! Well done, as always! The process is the most interesting thing of all. Somebody needs to write a book like "The Inner Game of Electronic Repair"...

[@raygianelli3612]

How's this for a title? "Zen and the Art of Stereo Repair". 😁

[@stirlingschmidt6325]

@@raygianelli3612 I might take it as a challenge! Went to college to be a music teacher, but took a different path…

[@Douglas_Blake_579]

Good to see you back at the bench! Nice diagnostics and, yeah, every Pioneer I've touched has had a real maze of a power supply.

[@raygianelli3612]

Hindsight being 20/20, I should have just checked all of them after deducing a power supply issue.

[@Douglas_Blake_579]

@@raygianelli3612 I think you got it right... you followed the evidence to a reasoned conclusion. I've never been a big fan of the "shotgun" approach.

[@1320pass]

Nice, Mr. G is back! Thanks for taking the time to share your knowledge and technique. 👌💪

[@raygianelli3612]

Thanks! There was a bar here named Mr. G's. Had a huge stage and a great house sound system. Gigged there several times, what a great place. Sadly no longer open.

[@bluesryder1]

Good job as usual Ray. You explain your diagnostics and trouble shooting very well. Look forward to more. I also have realized that accumulation occurs much easier than decumulation 😉, but I’m getting it done…moving soon too. Good luck with the strike…CWAStrong!

[@raygianelli3612]

Thanks for the shout out. Moving is for sure a pain, but it's time. Hopefully the strike doesn't drag out too long. Many of the younger folks can't afford to miss one paycheck, let alone more.

[@bill_p2074]

Glad you’re back online. I seriously doubt it will be a long strike nobody can afford a strike any more. I survived three strikes. Metro Atlanta is a good area. Climate is reasonable year round. Housing is no where as high as the area you live in.

[@TB-nz4kf]

Good to see back.

[@roroseppel2077]

Nice to see you back Ray ! 😀

[@jefftobin4034]

Ray, so glad you're back.

[@petercornell2002]

Thanks Ray, good to see you back

[@andymouse]

Howdy Ray ! great to have a repair vid, so what's up with Florida ? I thought it was a utopia !

[@herbward5240]

Ray, check the pnp input differentials , the blue caps on the amp driver board, and the pnp devices in the phono preamp and line stage. I do not remember the pnp device numbers . Also cracked solder joints in the PS on the dropping resistors.

[@robfors]

Welcome back!

[@willievivanco1]

nice to see you back ray,a d hope you get things done soon with your life my friend.first thing first, we always be here waiting for your excellent videos. ray one question do you have a nice distortion analizer for sale If you do please let me know tk in advance.

[@poormanselectronicsbench2021]

I hope your strike is a short one. I was on strike against Illinois Bell for a week and a half in 1983, but I was young and still living at home, so it was just an extended vacation. I can't see managers taking techs spots nowadays, especially in a CO environment or working on customer network equipment, as, very few, if any, know the requirements to even access the info needed to troubleshoot, resolve or install new new circuits or equipment. It's different to see how Pioneer powered some of the input amplification with a separate power supply, as most every amp powers that part with the same rail as the rest of the amp section, so I could see how that would throw troubleshooting the DC offset for a loop.

[@Wil_Bloodworth]

Welcome back Ray! Been hoping to see some more of your videos and I'm glad you put this one out. Sorry about your job! Why are you wanting to leave Florida? I bet those hurricanes can be a lot to deal with for sure.

[@raygianelli3612]

Wil, I'm concerned about the affordability/availability of windstorm insurance. Many companies are raising rates, or just leaving Florida entirely. My coverage has been rising by double digits for the past 5 years.

[@Wil_Bloodworth]

@@raygianelli3612 wow. Sorry to hear that is the case. Good luck with your next location! I continue to look forward to your videos and learning from them.

[@RPike-bq3xm]

Great video.

[@alanvandusen76]

I really dislike moving so don’t envy what you are thinking about doing. Good luck.

[@raygianelli3612]

Ugh, me too. I used to joke about having a "cleansing fire" instead. Now I pray I never have a house fire; I've made that joke so many times on line the insurance company is bound to find it. 😁 I had an elementary school teacher on Long Island named Mrs. Van Dusen. That I still remember her says volumes.

[@atw4321]

Please move to east Tennessee we need a good tech around here

[@garygranato9164]

good vid

[@kellyhubbard7952]

Thanks! I like to go to Florida, but if I stay too long??

[@Silent-Lucidity]

I think we work for the same company! :)