On Mar 4, 3:56�pm, Mike Coslo wrote:
" wrote roups.com:

* *Failure to properly
* *neutralize a final RF amp can result in heating sufficient
* *to melt the glass envelope enough to let air in and thus
* *destroy the tube (an 833 that was mounted on the control
* *console at Army station ADA for weeks as a reminder).

* * * * I would also suspect that when dealing with 15 KW transmitters,
errors would be pretty unforgiving.

What are the practical limitations of the Tube finals apparent
flexibility?

* *That's in many decades of old literature and covered
* *extensively. *Data from commercial service transmitters
* *is more comprehensive than amateur types as a
* *general rule. *Some of that may be hard to get now.

* * * * I'm going to have to try to find some of the literature.

Besides old ARRL Handbooks prior to the 1970s, I'd suggest
finding the site that has digitized copies of GE Ham News.
Those were (bi-monthly?) hand-outs by GE to push their
tubes (naturally) but they contained lots of different ham
projects (using tubes, of course).

I found such a site a few years ago but didn't bookmark it.
Was incomplete then but being worked on. The 1960s
was a good peiod for new designs in USA amateur radio.
I used to grab my boss' copies as soon as he was done
with them back then. :-)

73, Len