[R-390] Rats - There goes a pair of 26Z5W's

[Barry]

I had my working R390A on its back this afternoon with my project's PTO
connected to it.  I wanted to do some linearity checks on the PTO.  I
checked the endpoint settings and it needed a slight nudge to make it right.
As I was sticking the screwdriver into the PTO to adjust it, I heard the
sound like something was drawing excessive current.  I didn't see anything
amiss and tried again.  Another sound and the PTO stopped oscillating.
Checked and all filaments and lamps are still lit except for the 26Z5W's.
Both of them were completely blown.

I don't know if I shorted something to the full-wave rectifier mounted on
the back (I had the PTO sitting on top of the power supply), if I shorted
something in the PTO (I don't think this is the case as I've done this
before with a metal screwdriver without ill effects), or if it may have
simply been the tube's time to go.  I had inadvertently left the radio in
STDBY for about an hour and a half while the PTO was warming up for the test
(meant to switch to AGC but forgot).  Perhaps this placed some sort of odd
strain on the rectifiers.  I don't know.

At any rate, I now am two 26Z5W's short of a full supply.  Anyone have a
line on any?  I know there are available on eBay, but I thought this group
might have a source too.

Thanks,

Barry - N4BUQ