On Thu, 8 Jun 2017 17:28:02 -0000 (UTC), Cursitor Doom
wrote:

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?
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??

Insane ripoff. Good reason to never buy Marconi.

Looks like you ripped out the hole plating on one pin. With luck, it
will be one of the passive mounting pins.


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com