On a sunny day (Thu, 8 Jun 2017 17:28:02 -0000 (UTC)) it happened Cursitor
Doom wrote in :

Hi all,

I tore down a Marconi signal generator today. It's been awaiting my
attention for quite a while. Can't recall the model number off hand but
it does 10kHz to 5.4Ghz IIRC. I bought it from some chap who told me it
had a faulty smoothing cap in the PSU 'cos it was generating signals with
ripple on it. He told me he'd been quoted GBP280 ($387 in US dough as of
today's date) for a new replacement from Marconi and I bought it on that
understanding. Anyway, I tore it down today and located the said
capacitor. Here it is:

https://www.flickr.com/photos/128859...in/dateposted-
public/

This is the only pic that came out for some reason, but it's got most of
the important info on it. You can't quite see, but it has 5 terminals for
some reason, but on the board only 2 of them are connected. It's gone
seriously low-res internally, BTW, so *does* need replacing.

Questions: what makes this thing so special as to cost so much?
Why have the designers used such a huge capacity cap in this low current
drain application?

Nothing, it is a crappy old Philips, the contacts to the pins go wrong too.
Just replace with some caps with right capacitance / voltage and sintered wires,
not that crap.


If I can source a generic electrolytic of the same spec or better for
30 quid, why should I not use that instead of the bespoke replacement??