[time-nuts] Ancient OCXO in scope calibrator.

[Rex]

Rex wrote:
> 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
>
>
>   
Dang! Glancing again at the page just after I sent, the symbol IS an 
alternative form for a MOV, not a TVS. All the rest still applies.
-Rex