This all started a few weeks ago when my radon fan stopped working due to a ice jam.

It was at this time I found out all 4 of my geiger counters were non functional.

First to get fixed my trusty CDV-700

After a few tests I discovered the high voltage supply to the probe was way off.

Tons of parts out of spec.

Time for a rebuild kit!

part way though the upgrade.

After cleaning and checking everything over multiple times I went to test… voltages are off.. by a bit…

On closer inspection….

That transformer looks fuzzy….??

That isn’t fuzz!?!

Tin Whiskers!

Tons of them!

Even on the High voltage potentiometer 1/2 way across

So tiny it is hard to get a good focus on them.

No this is not a hair! That is a tin whisker going from the ground almost to the center of the high voltage adjustment potentiometer.