Hope this is not too late to be out of context, but our server has been
giving trouble for a couple of weeks, and I only read the interaction about
3-500's this morning.
I was off the air for abt 4 years, and my 3-500's were in storage. I can't
remember which way up they were.
On trying to fire up my linear again, they appeared to have gassed, causing
severe fireworks. I have managed to partially recover them by placing high
value resistors in series with the plates and allowing them to soak. The
getter then seemed to soak up enough of the stray air to allow me to apply
HT without the resistors in series. In fact the standing current is back
to normal, and I can generate abt 70% of the power I used to get.
They seem to run much hotter than before though, in spite of the fact that
I have doubled up on the fans, and again start to glow blue if I allow them
to get too hot. (I've run a pretty exhaustive check for parasitics)
(Some of you may have noticed that I use a lot of pauses while CQ'ing, and
that's the reason).
I would be surprised if this has anything to do with the orientation in
which I stored the tubes, but someone may like to put me right on that.
Any comments?
Greg, ZS5K
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