You are the absolute master of switch repair. Love watching you work. Overall, this one makes me desire the simplest equipment possible. This was quite a project.
That was a job. I admire your patience. I would have sprayed the hell out of that switch from the outside, or dunked in a vat of DeOxit before I attempted to take it apart...
Some jobs are satisfying and some jobs are a chore, this one was a bit of both. My biggest fear is something I might have missed or something that crops up later because I didn't test it long enough. I like to listen to the piece for a couple of weeks before giving it back just to make sure.
@@TrevorsBench mine does not get hot. But I would like to know how many watts it consumes at idle. That watt meter that you use is it easy to hook up to the receiver? Thank you
@@TrevorsBench I haven't run mine for about 8 months I have been using a technics integrated amp. So when I am ready to use it again I will use my regulated power supply to bring it up slowly.
Trev always brings an entertaining vid. Who needs go-go girls? That is a massive amp ! *Please try the metal polish method on a junk switch to determine its effectiveness. 🖖🏽
Does it really matter, I don’t know but Pioneer typically specified low leakage replacements for those orange caps. Thank you for contributing all these videos to YT. They are a pleasure to watch and your skills are an inspiration.
All the orange caps tested fine which was surprising as I usually see these drying up by now. I opted to replace them with audio grade and film caps so they will last another 40 years or so. Thanks for watching and the kind words, they inspire me to make more videos
Given the heat in there I’d expect more bad caps as well. I’ll plug Nichicon UKLs in the audio path or wherever LL is called for. Of course everything is out of stock
Much Thanks for in depth coverage on that volume assembly, because that is my problem, found one of those 1/2 ass power transistor connectors literally broke in 1/2, thought this would be the problem. No, this came from an area with way more humidity than that of where I live, and as every day pass's it gets worse from dry air which explains why it functioned when it 1st arrived.
For the oxedised switch: plain paper with some polish, copper / silver / (or even kitchen) polish. You can even slide these small copper contacts over the edge of a piece of paper.
Indeed, although I myself use a silver jewellery cleaning bath for the tabs and sliders separately, then rub the latter against a folded paper edge dipped in it. Then isopropanol bath and finally Electrolube 2GX contact grease. Contact resistance drops to miliohms and stays that way.
Really great troubleshooting video! I remember when these appeared on the shelf at my local stereo store...we all thought it looked space age. Still had the blue-line power meters though; there was a tremendous amount of circuit board real estate in this monster! Did the worrisome phrase "thermal creep/runaway" cross your mind? Scary when it happens...the owner will most certainly be happy with your thoroughness!
Heat is the big killer of electronics, it's always in my mind when I service gear. I look for ways to reduce it and, in turn, reduce power consumption if possible. Even something as simple as replacing incandescent lamps with LEDs can cut down on the heat generated inside the chassis. Thanks Craig for your continued support
@@TrevorsBench Yup. I hope it does not crap out on me. It been sitting for several months since I am using right now a Technics SUZ760 integrated amp it is also a 120 watts amp. When I bring the Pioneer back into service I will use my Variac to bring it up slowly. Thank you
Trevor, Much appreciate this because I should have 1 of these delivered in next day or 2. Goodness gracious, what have I got myself into.....................
@@TrevorsBench Yeah, got it for a reasonable price and seems to have an issue, Bass is heavily distorted and comes in and out and appears to get worse with every power-up. I think it may be those 1/2 ass spring loaded connectors for power transistors. Thanks to your video expressing this potential problem. Powers-up, about a 4-5 sec. delay, runs normal temp. So, here again watching this Great video on this machine.
I agree that sandpaper would be too rough on the plating, but have you ever tried a fiberglass pen to clean those? I find it doesn't really remove the plating and because it's flexible it goes into all the "shapes" of the contacts and removes pretty much all the bad stuff.
Those fibreglass pencils do a great job of cleaning small parts but they wear away with use and leave tiny shards of very fine glass everywhere ! That stuff gets into your skin, into cuts and scratches and can get into your clothing, it's only a minor irritation mostly but if it gets in your eyes or nose you'll regret it and it tends to spread around too so other people in the house and pets will be irritated by it !
Great job! Total noob here, but regarding the bias adjustments: Perhaps the best way to adjust it to give it a test tone and do an fft analysis on the output, and adjust the bias to have the least distortion. Again I am a noob, but with such an old device, perhaps the factory voltages are not the one which gives the best results, and perhaps setting the bias this way, will reduce power consumption more? Perhaps it was higher because of all these? :)
I need a volume Pot for it, This receiver with a pair of Vega's 380's will make your pictures fly off your walls, It will shake your house and your roof.
I am really liking your video, I am also trying to repair this system. The AWR 216 power supply board caps were melted into the board or really burnt when I looked at them. Though, what it looked like was that some glue was use to maybe keep them stationary? I have never seen caps being glued down, however, they looked like they had burn marks and they were also cracked. I am a bit of a newb with this system as its a bit more modern. I also took a look at the connectors, and one of the connectors was just unplugged I am curious to know if this was cause the caps to melt. Those connectors are just crap, its crazy that they decided to even use them. I might do what you did and do a proper connections. I would also like to replace the wires as well as I was concerned with the same thing as you, being solid core. These are old systems, so the only thing I am concerned about it finding the right parts. I would rather not have to rebuild something. Also how do you keep up with all the wiring? The schematic is really hard to read.
The caps on the power board were glued down at the factory. Over time the glue darkens and becomes acidic and electrically conductive. You can scrape the glue off as it's probably not holding anything at this point. The SX-D7000 isn't a good receiver for the beginner. It has lots going on and the wiring is a nightmare. One broken connection can disable it. I can't offer any advice aside from go carefully and take pictures as you go. Work on only one subsystem at a time and then test it before moving on.
Thank you for sharing your skills and calm demeanour. Just a quick question, at the end when you lowered the idle current, did you zero the DC balance again or leave it?
Hello Trevor, I enjoy your calmly approach to repairs. I get more frustrated when things get too convoluted, with multiple issues at once. But my question is regarding your ET LCR meter. Are you overall happy with it, and would you recommend it for mostly, good or bad decisions in repairing equipment? Keep them coming, as I learn a few tricks here and there, and is quite entertaining to watch your approach to troubleshooting.
Hi Gustavo, Yes I like it very much. The price was a bit high for my liking but it's proven itself to be accurate and easy to use. I actually use it more than I show. I find it's very good at showing the overall health of capacitors and resistors
Can you explain a bit why you have to set pot A to value A, then turn pot B to value B, all without changing the measuring point. It doesn't make any sense, unless one is for rough adj and the other fine adj. Thanks for the video.
I can't remember exactly but the service manual instructs to use the same test point and adjust two pots. First you adjust the lower bias then adjust the higher. This is the way Pioneers set it up, like it has two stages of bias depending on it's operation conditions
Sorry Ed, I can't help you. I'm not familiar with the RD-706. Look for dirty switches, belts that dried up and slip. I'm guessing it has some kind of automatic stop for end of tape, maybe look there if it's working properly?
You are the absolute master of switch repair. Love watching you work. Overall, this one makes me desire the simplest equipment possible. This was quite a project.
What a beast indeed! Need forklift certification to move it around the house. Great job again Trevor
Thanks Mike
It weighs 40lbs if I remember right
That was a job. I admire your patience. I would have sprayed the hell out of that switch from the outside, or dunked in a vat of DeOxit before I attempted to take it apart...
Some jobs are satisfying and some jobs are a chore, this one was a bit of both. My biggest fear is something I might have missed or something that crops up later because I didn't test it long enough. I like to listen to the piece for a couple of weeks before giving it back just to make sure.
I am really enjoying your projects, we got more than a few times, had the same gear. Great stuff, thank You.
Thanks, stay tuned lots more stuff coming up
Always a pleasure to watch your content, Trevor. Great job as always and I especially liked your solution for the connections to the transistors.👍
Thanks
@@TrevorsBench How many watts does it consume at idle? or did you cover that?
Thank you
@@TrevorsBench I saw that you did cover the power consumption at idle 75 watts ouch!
Beautiful amp, excellent repair! Awesome work, Trevor. Again, thank you for another great video.
Thanks Alexis, I hope you're doing well
@@TrevorsBench I have this receiver. Bought it at a thrift store for five bucks a few years back, it is an excellent receiver.
@@TrevorsBench Where can I buy one of those watt meters?
Thank you
@@TrevorsBench mine does not get hot. But I would like to know how many watts it consumes at idle. That watt meter that you use is it easy to hook up to the receiver?
Thank you
You do great work . I like how you keep your videos PG rating.
Thanks, I try
@@TrevorsBench I haven't run mine for about 8 months I have been using a technics integrated amp. So when I am ready to use it again I will use my regulated power supply to bring it up slowly.
Trev always brings an entertaining vid. Who needs go-go girls? That is a massive amp ! *Please try the metal polish method on a junk switch to determine its effectiveness. 🖖🏽
I'll get some and have it handy next time I tear into a switch. I'm curious how well this works, thanks for the suggestion
yay!
Enjoy!
Does it really matter, I don’t know but Pioneer typically specified low leakage replacements for those orange caps.
Thank you for contributing all these videos to YT. They are a pleasure to watch and your skills are an inspiration.
All the orange caps tested fine which was surprising as I usually see these drying up by now. I opted to replace them with audio grade and film caps so they will last another 40 years or so. Thanks for watching and the kind words, they inspire me to make more videos
Given the heat in there I’d expect more bad caps as well. I’ll plug Nichicon UKLs in the audio path or wherever LL is called for. Of course everything is out of stock
@@TrevorsBench does that board need wires to be unsoldered in order to take it out? Or does it just have plugs?
Much Thanks for in depth coverage on that volume assembly, because that is my problem, found one of those 1/2 ass power transistor connectors literally broke in 1/2, thought this would be the problem. No, this came from an area with way more humidity than that of where I live, and as every day pass's it gets worse from dry air which explains why it functioned when it 1st arrived.
For the oxedised switch: plain paper with some polish, copper / silver / (or even kitchen) polish. You can even slide these small copper contacts over the edge of a piece of paper.
Good tips. I need to remember this for next time, I'd like to try it
@@TrevorsBench Fold the paper a few times, and one time for the little slider contacts.
Silver cutlery cleaners also do the job pretty well
@@TrevorsBench The receiver isissing it's wood side covers.
Indeed, although I myself use a silver jewellery cleaning bath for the tabs and sliders separately, then rub the latter against a folded paper edge dipped in it. Then isopropanol bath and finally Electrolube 2GX contact grease. Contact resistance drops to miliohms and stays that way.
Too late now but for future reference, you can find a lot of sub miniature lead lamps etc at model train hobby shops.
Thanks, good to know. In this case it was a good excuse to do a LED retrofit.
Really great troubleshooting video! I remember when these appeared on the shelf at my local stereo store...we all thought it looked space age. Still had the blue-line power meters though; there was a tremendous amount of circuit board real estate in this monster! Did the worrisome phrase "thermal creep/runaway" cross your mind? Scary when it happens...the owner will most certainly be happy with your thoroughness!
Heat is the big killer of electronics, it's always in my mind when I service gear. I look for ways to reduce it and, in turn, reduce power consumption if possible. Even something as simple as replacing incandescent lamps with LEDs can cut down on the heat generated inside the chassis. Thanks Craig for your continued support
I found my Pioneer SX-D7000 at a thrift store and it only cost me $ 5.00 bucks
My best find ever!
Wow. That's incredible, these things are rare
@@TrevorsBench Yup. I hope it does not crap out on me. It been sitting for several months since I am using right now a Technics SUZ760 integrated amp it is also a 120 watts amp.
When I bring the Pioneer back into service I will use my Variac to bring it up slowly.
Thank you
@@TrevorsBench I did have the Pioneer in the rotation before.
Man this one was really good
Trevor, Much appreciate this because I should have 1 of these delivered in next day or 2. Goodness gracious, what have I got myself into.....................
LOL, they are beasts. Hope it's working well for you
@@TrevorsBench Yeah, got it for a reasonable price and seems to have an issue, Bass is heavily distorted and comes in and out and appears to get worse with every power-up. I think it may be those 1/2 ass spring loaded connectors for power transistors. Thanks to your video expressing this potential problem. Powers-up, about a 4-5 sec. delay, runs normal temp. So, here again watching this Great video on this machine.
I like that turntable it is easy to move that massive amp around.
I agree that sandpaper would be too rough on the plating, but have you ever tried a fiberglass pen to clean those? I find it doesn't really remove the plating and because it's flexible it goes into all the "shapes" of the contacts and removes pretty much all the bad stuff.
Those fibreglass pencils do a great job of cleaning small parts but they wear away with use and leave tiny shards of very fine glass everywhere ! That stuff gets into your skin, into cuts and scratches and can get into your clothing, it's only a minor irritation mostly but if it gets in your eyes or nose you'll regret it and it tends to spread around too so other people in the house and pets will be irritated by it !
hello, thanks for another charge, I'm waiting every day for a new video, otherwise the amplifier repairs are the most, thanks a lot !!!
Great job! Total noob here, but regarding the bias adjustments: Perhaps the best way to adjust it to give it a test tone and do an fft analysis on the output, and adjust the bias to have the least distortion. Again I am a noob, but with such an old device, perhaps the factory voltages are not the one which gives the best results, and perhaps setting the bias this way, will reduce power consumption more? Perhaps it was higher because of all these? :)
I need a volume Pot for it, This receiver with a pair of Vega's 380's will make your pictures fly off your walls, It will shake your house and your roof.
I am really liking your video, I am also trying to repair this system. The AWR 216 power supply board caps were melted into the board or really burnt when I looked at them. Though, what it looked like was that some glue was use to maybe keep them stationary? I have never seen caps being glued down, however, they looked like they had burn marks and they were also cracked.
I am a bit of a newb with this system as its a bit more modern. I also took a look at the connectors, and one of the connectors was just unplugged I am curious to know if this was cause the caps to melt. Those connectors are just crap, its crazy that they decided to even use them. I might do what you did and do a proper connections. I would also like to replace the wires as well as I was concerned with the same thing as you, being solid core. These are old systems, so the only thing I am concerned about it finding the right parts. I would rather not have to rebuild something.
Also how do you keep up with all the wiring? The schematic is really hard to read.
The caps on the power board were glued down at the factory. Over time the glue darkens and becomes acidic and electrically conductive. You can scrape the glue off as it's probably not holding anything at this point. The SX-D7000 isn't a good receiver for the beginner. It has lots going on and the wiring is a nightmare. One broken connection can disable it. I can't offer any advice aside from go carefully and take pictures as you go. Work on only one subsystem at a time and then test it before moving on.
so the seller said it was working huh...RIGHT!!!
Well, I'm guessing he plugged it in and it lit up, that was the extent of his testing. That power supply board was really messed up
@@TrevorsBench indeed it looks like it was. Well done to get it all back up and running, more of these classic amps/preamps need to be conserved!
Thank you for sharing your skills and calm demeanour. Just a quick question, at the end when you lowered the idle current, did you zero the DC balance again or leave it?
Thanks. I did check DC balance a few times off camera. Adjusting bias won't affect the DC balance, the two are unrelated
What tool is that that you used to check the power consumption and where can i get one?
Thank you
Hello Trevor,
I enjoy your calmly approach to repairs. I get more frustrated when things get too convoluted, with multiple issues at once. But my question is regarding your ET LCR meter. Are you overall happy with it, and would you recommend it for mostly, good or bad decisions in repairing equipment?
Keep them coming, as I learn a few tricks here and there, and is quite entertaining to watch your approach to troubleshooting.
Hi Gustavo, Yes I like it very much. The price was a bit high for my liking but it's proven itself to be accurate and easy to use.
I actually use it more than I show. I find it's very good at showing the overall health of capacitors and resistors
Nice video. Which power meter are you using? It looks handy.
Does the volume knob have allen screws to remove it??
Can you explain a bit why you have to set pot A to value A, then turn pot B to value B, all without changing the measuring point.
It doesn't make any sense, unless one is for rough adj and the other fine adj. Thanks for the video.
I can't remember exactly but the service manual instructs to use the same test point and adjust two pots. First you adjust the lower bias then adjust the higher. This is the way Pioneers set it up, like it has two stages of bias depending on it's operation conditions
That receiver is missing the wood side covers so its wider than the 20 inches he mentions.
I have a panasonic reel to reel model rd 706. The machine comes on, but stops.anything.any suggestions?
Sorry Ed, I can't help you. I'm not familiar with the RD-706. Look for dirty switches, belts that dried up and slip. I'm guessing it has some kind of automatic stop for end of tape, maybe look there if it's working properly?
Looks like its missing the wood cover sides.
Didn’t this unit have wood sides ?
Very similar to the sx-3900 as far as amp and preamp