just another note to add...... Great Video by the way!!but when I clean the face on these old Aluminum face units I try to wipe/clean/steel wool in the SAME direction as the grain in the aluminum, not cross grain as shown around 17:00...... you will scratch it and will change the reflection when the light hits it...... I'm cringing to watch that part.
thulinp, the noisy transistors are quite common in several old pioneer and Marantz units. In the Marantz units its the 2SC458 chips that are really noisy, they are easily subbed with KSC1845. If you noticed, I had recapped the entire phono board and the noise still existed, that's when I knew it was the transistors. Here is an entire thread on these noisy transistors in the Pioneer SX series phono stages on audiokarma. There are several other threads on the web about them too. It sure fixed the issue on this one. Hope this helps shed some light that it is somewhat common. I know I run across it a few times a year but then again, I probably work on a dozen units a month. www.audiokarma.org/forums/showthread.php?t=518421
Blueglow Electronics wow it kinda looks like the pioneer reciever i sold 7 yrs ago when i lived in mass! and yes it also had those same etchings on face plate when i got it. btw im a member of ak as well :)
I had static on my phono input also. When I checked out the phono board there was a blow resistor on it. Turned out that one of the power supply inputs was 30 volts higher than the spec. I had to replace a transistor on the power supply board. I then replaced the blown resistor on the phono board and the static is gone. I really should rebuild the phono board.
Thanks for the post. I was able to detox my pioneer SX850 following your directions. You made the disassembly and re-assembly easy to understand. I would never have tackled this without your video. My reciever sounds crisp and clear. Thank you for your time and sharing your knowledge.
Enjoyed your process. I do the same sort of thing for the same reason. Always good to find out how others approach a project. Always learn something. Townes! Nice!
Tried to find something more recent to ask this question. Can you recommend what cleaner to use on faceplates Marantz, Pioneer and Sansui and others. Don’t want to damage lettering and stencils thank you!
I have an sx-850 I just purchased. Any idea what can cause the sound to not work, and the work again. Happens intermittently. Will not work, then I can turn on later and it works.
Was wondering how I can figure out my pioneer Receiver or if someone can lead me in the right direction.when I power the sx-850 up the signal gauge works and the FM stereo light also comes on but yet no sound out of the speakers.all fuse's inside the stereo are good. Wordering how to check the amp. Would the stereo not work if amp is not working? Thanks for any help..
I have this same SX850. The volume intermittently gets real quiet and then loud again. I have tried working with speaker wires and it still does it. Any idea what would cause this so I know where to start?
I have the same receiver where the right speaker is intermittent until I play with the muting switch on the right side of the unit. Would that be just a dirty switch causing that? I am now considering cleaning my receiver after watching your video. Thanks
I live in Washington state I have an SX 850 it needs a rehab like that I think what does the price like that rent is there any money in Washington state or are you much to state that could do it
It looks like somebody is forcing you to speak or you are highly introverted...it doesn't look that you enjoying what you r doing...this is my impression...your r breeding heavily and sounds like having really sort of permanent pain...my impression...sorry...
Thanks for documenting this nice restoration. One thing though... my schematic for the SX850 shows 4 ea. 2sk1313 (npn) and 2 ea. 2sa725p (pnp) on the phono eq board. But did you just put in six of the same type, all npn? And it worked? Or did I miss something... ??
I have a SX-1250 that's in need of a restoration. I hate to ask a ballpark figure on what that would cost because hidden issues could pop-up but could you give me a figure that the price could fall between. (Like would it be between $500 to $1000 or is it more?)
Nice video! I love electronics and stereo repair. I just started a 1060 Marantz... Haha I have a wife who leaves half drunk drinks all over the house! M Very nice stereo there. Subscribed!
I like cleaning the entire component first. It shows any issues on the boards and is great for motivation in repair in seeing it's cosmetic condition markedly approved. Microfiber cloth is my preferred cleaning method especially on the faceplate.
That solder sucker is one of the best tools I own. Worth every penny. Little silicon tube at the end gets torn up, but it works great without it. Awesome tool. I highly recommend it as well. Money well spent.
I just tackled the same problems on the SX 950 and that's typical - but how long have you had YOUR Fluke 8062A? My other meter resembles your orange sheath model, which I bought for added functions like cap and gate tester. Talk about parallel mindsets!
Mine is a garage stereo and the pots started getting scratchy and the turn tables 1&2 were dirty. I had to push them in and out to pick up both channels. Took me about 2 hours, but it works great now. thanks for the video. I just have to send my 1250 to a shop to get it rebuilt.
Just got one of these and one channel wasnt working right so I cleaned all the switches and potts and works fine until I tried the phono and guess what, exactly what yours did. Did you only replace the six transistors on that board, were they all the same type.
The last one I repaired was Pioneer SA-6300 (changed driver transistors ) but the pioneer board was poorly marked, took me 15 minutes to locate the transistors - bec was arranged differently so used Chinese tester to work pin out. Sansui's and Marantz are marked well.
I have a sx850 amplifier. It crackles and pops when you turn it on. Some times I wonder if its going to bust the speakers. One time I just kept it on and let it alone for a while and it played well on all functions. The next time I tried it, but it crackle, pop then no more sound. What circuit do you think it might be in. My father in law took it to a repair shop earlier for the same problem. I know your busy so if you can't respond , I understand. Thank you.
Any tips on how I can replace or fix the volume control on my old Pioneer SX508? I'm assuming the volume control is the problem because many years ago the right side watt meter and speakers would cut out. I'd jam a matchbook behind the volume control knob and the watt meter and speakers would come back on. As time went by the matchbook trick wouldn't work anymore. The right side watt meter doesn't move at all, the left side only moves a little, and I can't get any sound outta it at all. I called Pioneer and a I got the response I expected, obsolete part, can't help you, and can't help you find a compatible replacement. But at least Pioneer had the belt drive for my 70's PL-A35 turntable which saved it from turntable heaven...
Hi Blueglow electronics my name is ted i have question, i am working on a vintage 1980 to 81 pioneer sx-780 receiver i have to replace both power packs and two resistors, now the resistors that are in the receiver are square and say "0.22 ohm k" at "02 watt" with two squiggly connectors that go into the board next to the power packs witch are the stk-0050 darlingtons the ones i found are .22 ohm 2 watt Sprague they are the round type "will these work" in place of the originals please let me know i would really appreciate it, i can't find the original type that are in the receiver, thanks ted
Good job. I am currently working on a late 80's Kenwood KA-109 receiver, I'm replacing every cap and trying to figure out why its dropping input channels. I only have phono now and it bypasses the IC which selects inputs. I dont think I Can solder a new chip because it is 28 pin and lugs are too close. I cant find a used board. I may just rewire the phono channel to CD level input because thats all I use.
Hey, Love your videos! I'm just down the road from you in Greenville, SC! I'm restoring a Pioneer 1280 atm and was wondering what I should charge? I'm replacing all the electrolytic caps, and de-oxidizing all the switches and relays, and basic dust removal. thanks and keep up the great videos!
Beyond getting it plugged in and playing music, I know nothing such as you were doing but I was so fascinated I watched the entire video. It made me think of my old Pioneer SX-939 that I bought while in Okinawa in 1976. Having "learned" so much from your tutorial video I suspect there are several bad caps and the push buttons on the front need some cleaning. Don't really know what to do with it. From the posts taking it to a Pioneer service center is hit or miss. Years back I called one and they wanted $75 just to open it. Hate to see it RIP after yielding so good times. You need some spare parts? Great post.
Hey mark! I just picked up a pioneer sx430 and need to replace the FM indicator lamp. The manual says it needs a 6v 30ma bulb. All i could find is a 8v 20ma bulb. Will this work? Love the channel! shane
I really don't get why you switched phono amp transistors. The noise you got is very typical of bad caps. I've never heard of a transistor going noisy like you said.
I'm wondering if you can helpe me pioneer sx-580, i was replaceing 5 pin transistor on the left channel affter i turn it on there was a hum and left meter max out. I found out that i put in the 5 pin transistor backward. I dont know if something blowout or if smoething happen to the to the transformer. Do you know where i could start troubleshooting at ? REPLY
Great video just got a Sx-850 and you provide great detail on the inner workings of a classic receiver. Not many appreciate the details of the old components. Mine had bad caps and one of the switches needed cleaning.
I have a Pioneer Stereo Amplifier Model SA-6200. I did some repairs to this amp over the past few years.I need to replace the output transistors and some of the other transistors in the main board.I will like to obtain the schematic diagram.
I think you’re better off replacing the wiring for the bulb entirely. The solid core wiring in these amps is pretty brittle and can break internally... as neat and pretty as the original wire wraps are, I recently replaced a fair amount of wiring with new stranded hook up wire and soldered it, the amp had been worked on a couple of times before and came to me with various issues, a few of which were due to broken wires. It’s singing beautifully now and sounds way better than I’d expected, the customer is over the moon with the results.
I use 0000 steel wool on any Glass Face and the glass shines like new.. This is how high end detail shops clean glass on cars. Just make sure it's Glass and not cheap plastic.
from guadalajara mex.i need repair my amp sx 950 ,please where i can find the pieces the preamps. if you know where i do it send me the information tank you
on the steel wool I use 00000 - this is the finest that i have found- if it does scratch - its so fine the naked eye can not see it --- at the very end of my repairs _ I use a fine wax for metal and it keeps dust and dirt down off of it
Thank you for these videos, these educational videos are one of the things that the internet is supposed to be used for. I hope to get my SX-950 left speaker fixed soon.
i found a receiver like it fool of nikatean from a smoker i sprayed it with oxy wash then hosed it out came out spotless like ney dried in front of a fan for days befor turning on sounds good will that hurt it i have another one wear the power caps swlen on the top but sound good i can push the top down flush with the inside is it just the plastic top cover thanks
i find many conponents dont have a fuse from the factory so i put one in with parts from radio shack see in my chanel i show how i do that is it istaped decks and cd players i find that in thanks
Nice! very educational, good tips on the phono stages would love to see you demo how to align a tuner properly. something I've yet to try. good luck with you projects.
Theft was a huge problem back in the 70's, but some people went berzerk with the etch pens.. really.. the glass? (hate to see that anywhere) Blowing out the chassis carefully is ok, but makes a lot of dust. Much more tidy is to vacuum with a soft brush, smaller brushes for the boards. Likewise I am not a fan of deoxit. Regular contact cleaner does a great job IME, never a problem, and NO acid to cause potential oxidation later on. (why introduce it to valuable OEM parts?) For the most part, switch contacts and pots are not oxidized, but just have a layer of dust and decades of resin deposit from the air. The faceplate can be cleaned with 3M finesse-it, about $60.00 per bottle, outstanding for cleaning metal and gloss painted surfaces. It is gentle and will remove tape residue too, without use of chemicals or steel wool. The cosmetic part can be challenging to restore to near mint, without appearing "worked on". The right cleaners and chemicals and procedure are critical. Some of the procedures in auto-body detail can be applied to electronics cosmetic restoration.
The preserver in some types of deoxit contains a conductive additive to enhance electrical contact. This same additive can also leak resistance to ground, and change the value of the pot, switch (which should be fully open when "off") ... another reason to not use it. (only as a last resort if contact cleaner does not work... which it does 99%+)
I have 2 980 SX. Want to do a proper cleaning and go through. I won't lie I am a tad intimidated. What is the best way to deoxit and clean all the switches? I have the faceplate off, can I just spray them and work the switches to get them cleaned up?
