1948 Capehart trouble

[Eric H]

I'll confess, I recapped this set, it used to be mine.

Kirk, how long does it have to run before the trouble starts?

I fired the set up a few days before I took it to your parents house and it worked OK, I didn't run it a long time though, maybe 15 minutes or so.
I Know it hasn't been run more than an hour total since it was recapped.

I can't imagine what would cause an arc inside the tube other than a bad tube or way too high HV?

There are some adjustments down on the side of the HV cage accessble through the bottom door, check and see if there is a HV adjustment?