Overheated MV209?

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Overheated MV209?

Jason Hissong
Ok,

I think I probably was being a little to particular about making sure
the varactor diodes were completely flat on the board as I kept
reheating the leads until it would go flat (but they wouldn't as I
forgot there was a little nub of wire in the middle that would prevent
it).  I think I blew two of them... D24 and D25.  I took a DMM and
measured across d24 and d25 (in circuit) and it showed 42.5k both ways.  
Whereas, on the others, it would indicate high resistance (or infinite
resistance) both ways.

I used my handy M3 transistor checker (I don't know if it can test
varactors properly or not) but the tester indicated no leakage current
on  the good ones and the leakage current was too high for it to measure
(it goes up to 25uA and anything above it will show ---).

Soooo.. I think I blew these two parts.. sigh...  am I right?

Jason

--

"A long journey starts with the first step and an understanding spouse."
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Re: Overheated MV209?

Mike WA8BXN
If they are still in the circuit, the readings you are getting may be from
other components. I would not worry about them at this point, and just
continue building, they probably are ok.
 
73/72 - Mike WA8BXN
 
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