Capacitance and voltage problem

frisouille

frisouille

French menber
Hello everybody,
I'm back with a new amp restoration a yamaha PC-4002m. My question is about two caps on the main board (signal path) that have exotic voltage range: elna for audio 100uf/120v.
The 120v caps doesn't exist in the major audio grade caps (nichicon-elna).
Some guys suggest me to put in series or parallel to obtain the right capacitance with the right voltage.
I thinking about using two nichicon in series (220uf/80v) so it'll give me 110uf/160v.
My question is about the capacitance which is too high in front of the original rating(100uf/120v).
Is it not recommended or it'll be acceptable?
Thanks for your precious help.
 
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Why is a 100uf 160V cap not acceptable?

Series'd and parallelled caps are a kluge and to be avoided except as a temporary test when troubleshooting.
 
Thnak you EchoWars,
Do you think that the tolerance will be insignifiant? It's the first time that i've this sort of question. I'm pretty sure that you're better than me in this case of problem. which model do you advise me?
PS:I begin an order in mouser.
 
I'd look for a cap that is the same diameter as the original, or close to it. Fill me in on the diameter of your part and I'll look for some appropriate parts from Mouser.
 
Greetings AK 'Ami'

older audio path elna's in USA market were black. New elna simicII serve the same purpose at rated lower v's. so I'd just put in the 100v 100uf simII's as I seriously doubt a preamp is going to see that v spike with all the digital chips not seeing much. audio path caps are filters, supply from rails are service types or commons. But I have paralleled a 30v cap at 1 or 2uf to service rate a circuit
 
LOL! avionic... I look at so many sm's and look up's and often mix up euro models and just the damn model number - xxx. :D

However would that circuit see 100vdc potential and why complicate using a parallel solder in? I saw 100v 100uf elna simicII caps in england online for about 4 euro and you're in france so cost was something I didn't add in.
 
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Binkman said:
LOL! avionic... I look at so many sm's and look up's and often mix up euro models and just the damn model number - xxx. :D

However would that circuit see 100vdc potential and why complicate using a parallel solder in? I saw 100v 100uf elna simicII caps in england online for about 4 euro and you're in france so cost was something I didn't add in.
Click to expand...
Don't know until I can review a real schematic. Hint hint OP !:D No- hifiengine is not a real scat.
 
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The baby with vu-meter warm led conversion. The next step is inside the beast...
 

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C219 & C220 B+ & B- rail caps.

Q? what makes you think these are bad? and if desiring to replace just up the V rating and closest size match.
 
Don't know if they are bad, just the story of thismap that was very used for music tour; And the which to give ita new "lifting". What do you advise me for this 4 caps. Elna silmic are 100v rated max.
 
The 100uf 120V caps are nothing more than a local filter for the supply rails. Pretty much any high-quality cap will do just fine there. Don't overthink this.

12.5mm x 20mm 100uf 160V United Chemi-Con:
http://www.mouser.com/ProductDetail...=sGAEpiMZZMtZ1n0r9vR22Xu7SfxIKJmdN/IaDElfe44=

12.5mm x 25mm 100uf 160V Nichicon:
http://www.mouser.com/ProductDetail...GAEpiMZZMtZ1n0r9vR22TZ4hs%2bw0LzJrpYCTojVbqc=

12.5mm x 20mm 100uf 160V Panasonic:
http://www.mouser.com/ProductDetail...=sGAEpiMZZMtZ1n0r9vR22dN7zJS18SGVsbstDos7wfw=

10mm x 30mm 100uf 160V United Chem-Con:
http://www.mouser.com/ProductDetail...n0r9vR22VRmzOGR10zU928FnL%2bKiyXX5H2sNEYzgQ==

That last one is unwieldy in a 30mm length. If you can squeeze a 12.5mm diameter cap in there, then there are a lot to choose from.
 
thanks very much EchoWars. So you think that this 4 caps aren't in the audio signal path?! I can finish with this problem.
Another question, the fan cooling run permanently also it should be cuts off. The voltage depend of temperature with 2 modes low speed 60°c and high speed 80°c. Do you think that it can be a relay problem? The 2 relays are cheap so i can change them but i don't know which model i can take. It's an old matsushita series (JE1XN-DC24V-H).I've check the voltage at the fan and it's about 62v.
 
Mon ami; the caps are probably good for now. if you had a scope? you could detect any 'noise' but if speakers or headphones appear 'clear'. no hum etc then probably okay. These caps service the rails that service the amplifier signal path so you can move on if rail V's are steady. You can always replace later if just diagnosing.

perhaps Avionic can comment on the fan? 62vdc? Pics would probably help.
 
Thanks Binkman.
No i don't have a scope but the amp run well, no hum, the offset and idle current are good too. It's ok for the caps, i'll go with( 661-EGXF161ELL101MJ3) united-chemicon 100uf/160v.
For the fans, they both run without any temperature overheating so i testing the voltage who is about 60-62v and the fans turn. I think that the voltage should be about 0v and when the temperature reach 60°c they will go on.
They're two relays on the signal circuit board that control the fan. I upload the SM that can give some way for searching the guilty.
 

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