I thought tantalums were noted for spectacular failure events. If this is indeed my shorted component, it simply failed quietly which I didn't expect. I'll have to lift one side to see if that's the problem (but do suspect it is).
The odd thing is this failure mode was intermittent for a quite a while with failure events lasting a second or so in between long periods of symptom-free performance. I just didn't think tantalums failed that way but maybe so.
Thanks,
Barry - N4BUQ
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----- Original Message -----
From: "Harvey White" <madyn@...>
To: [email protected]
Sent: Wednesday, May 30, 2018 8:51:16 AM
Subject: Re: [TekScopes] 465B - Question regarding C4331 / CR4405
On Wed, 30 May 2018 09:29:11 -0400 (EDT), you wrote:
Checking a few things in/around the LVPS of my 465B and noticed that TP4339
checks shorted to ground. I presume that's most likely C4331 or CR4405.
Looking at the board, C4331 appears to be a rather large(ish) bulb-like
device which I took to be a tantalum; however, the parts list shows that as
a 47uF electrolytic. The colors tend to agree with those numbers (e.g.
yellow dome, violet middle, etc.) but is that indeed an electrolytic or
tantalum?
I'd go for a dipped tantalum. They're known to fail.
Harvey
I can share a picture but this cap hangs out right next to TP4339 (+15V test
point). Anyone know?
Thanks,
Barry - N4BUQ
