[sdiy] capacitor ID please

[ChristianH]

Hi Mark,

these are multiple electrolytics. I have seen them ages ago when I
tinkered around with old TV sets.
The half circle, square, and triangle denote separate pins at the bottom,
other sides of the separate capacitors are usually connected either to a
common pin with no special sign, or simply to the metal case.

The numbers appear to be 40 microfarads (usually written as MF or MFD),
400 volts.
No idea about the other numbers, back then sometimes a production date
was indicated, that _could_ be "6137": week 37 in 1961.

If it's an electrolytic from the 60s, then it most probably needs
replacing, those don't last for decades.

I think the chances of obtaining caps like that today are around zero.
You should go for separate caps, most probably they will be smaller in
size than the old one. But be sure to stick to the 400V rating or better...
Capacitance doesn't have to match exactly, since electrolytics have huge
tolerances specs anyway, 47 or 50 uF will do fine. And if it's a power
supply circuit, most probably 100 uF won't do any harm either, but
that's just a guess.

regards
Christian


On Fri, 05 Jul 2002 11:22:06 -0400 markus wrote:

> in an old tube console stereo amplifier from the 60's i was surprised to 
> find only one large aluminum canister-type cap. it reads :
> 
> 40MFD 400WV (half-circle icon)
> 40	400	(square)
> 40	400	(triangle)
> 200	50	
> 1013	6137 FP
> "stereo 33" sticker on top of the canister
> 
> 
> what kind of cap is this? how do i determine if it needs replacing ? what 
> would be a good replacement ?
> 
> TIA
> mark scetta