[time-nuts] Ancient OCXO in scope calibrator.

[Rex]

Brooke Clarke wrote:
> Hi Dave:
>
> Do you have a photo?
>
> It's been my experience that older electronic equipment fails because of poor 
> connections rather than bad components.  For many examples see:
> http://www.prc68.com/I/HaT.shtml
>
> Have Fun,
>
> Brooke Clarke
>   

Brook,

A little off topic from the original thread, but on your referenced 
page, in the "Dead CRT Computer Monitor" section, the blown device is 
probably a TVS (Transient Voltage Suppressor). My first thought was that 
it was a MOV (Metal Oxide Varistor) but the symbol was different. With a 
bit of Google, I found this page:
http://books.google.com/books?id=4SkqFozu80MC&pg=PA122&lpg=PA122&dq=schematic+symbol+MOV&source=web&ots=VydlPTFGNA&sig=A8fKQfYQ3Agb0OU8iEMwM9Zhdsc&hl=en&sa=X&oi=book_result&resnum=1&ct=result#PPA122,M1

(Wow! What a URL. Good chance it will wrap in the email. If you can't 
copy that, it is page 122 in the google online book "Embedded Systems 
Design Using the Rabbit 3000 Microprocessor". Seems like a pretty good 
description of voltage suppressors if you scroll back and forth a few 
pages.)

So I just thought I'd try to help with the device, as your page still 
has it as an open question. Still unknown is the voltage rating and what 
caused it to blow. Since you mention it was on the AC mains, there is a 
good chance it was just doing what it was supposed to do, and the 
voltage should be something a bit greater than the AC input voltage.

-Rex