I’m working on a Pioneer SA-9500 amp that’s fully functional, but the owner wants a new power switch. Years ago, the original was replaced with a toggle switch, and now they’d like a push-style switch instead. I’ll also clean all the controls and switches, and I’ve made a list of electrolytics. For those, I’m going with Chemi Con since most of them are already that brand. Two of them are 470µF at 80V, and I noticed Mouser has one with an ESR of 36 mΩ at 1.65A ripple current and another with an ESR of 33 mΩ at 2.4A ripple current. Since they’re in the power supply, I figure the higher ripple current is better, right?
I will up load some photos of the Ampifier and my progress one thing I did notice on the lower tone board there is that nasty word "Tantalum capacitors" also some the electrolytics are Sanyo brand .
Just FYI, though it is not important here, but your ripple current is shown at 100kHz.
Typical multiplier at 120Hz is 0.7 (not shown in the datasheet in this case).
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
I went and looked at the sch.
If we are talking of C4/C5 (C6/C5) rectifier filters (I have Electrotanya copy, the quality is iffy), I am not sure if it shows +/-60V or 80V voltage at the inputs of the 48V regulators, at 220V version it does look both as 60 and 80, but while 80V WV is sufficient for 60V, I would bump it up a bit. If it is 80V, it is downright inadequate but, this being Pioneer, I give them the benefit of the doubt
In Telecom AT&T required us 4x for WV (read 20V WV for 5V circuit), and this is overkill (this was with redundant power supply arrangement), but my personal preference for stabilized voltages (after the transition), at least 50% margin (1.5x), better 100% (2x).
If you have bought these already, it is good too. I myself am not sure I care about the next generation using these. But when I do it, I do it for my own sense of "done right."
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Hello Mike,
I was trying to find a clear schematic. The two I mentioned are 470 uF at 80 volts , and the main filter capacitors are 18k uF at 63 volts. The biggest challenge is tracking down those two, and another issue is mounting the power switch. In the past, a toggle was added by hacking part of the chassis to fit it onto the faceplate, and I think the faceplate was drilled with a larger hole.
Sincerely Richard
Hello Mike,
Regarding Mouser, there aren’t many options for what they have in stock. There’s a guy on eBay who sells a kit for this amp, but it comes with everything, including the transistors. People on YouTube say that if the leads are tarnished black, you should replace them. As for the transistors, this unit works as is, but the electrolytics are going bad—on the power supply board, the plastic covering is shrinking as they bulge.
Sincerely Richard
Hello mike ,
The one that are in it have posts with wires soldered to them they are not threaded type .
no I have not found some yet I can also call mouser durinng my lunch time and their research can so if they can find me something that is not listed.
Hello Mike,
No, those will work just fine, and as far as size, that’s not an issue—I can make them work. I’ll check to see if they have them in stock, and they’ll check their shelf. I’ve been buying from Mouser since the 1980s—what a great company.
Thanks for your help, Mike. I’ll post some more photos and keep you all updated on how it’s going.
Sincerely Richard
I rarely call Mouser, except sometimes when have have some problems with search.
I simply create a project, add parts and place the order. Even though I remember their phone by heart, 1-800-34-Mouser.
If it shows stock, it is stock. If it is not, it will warn you when ordering.
I would grab that couple at the first link that shows 2pcs, it is still there. And $9 shipping.
It is Illinois capacitors, supposed to be a reputable company.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
Hello Mike,
Great minds think alike, because I do the same thing—I create projects like this one I’m calling it the Pioneer Amp. And yes, I use Illinois capacitors, and on that power supply board, did you notice the bad capacitors?
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