>I have to agree with Peter, I can't imagine a 723 being a "good
>choice" for an IC near strong RF fields.
Instead of trying to imagine, why not try trying to see if it works, Mr.
Rauch?
>I seriously question the
>carte blanche statements about bypassing ("do this, it always
>works").
- If the designer does not bypass for the range of frequencies involved,
what then? The Vcc multi-C bypass technique I use is SOP in solid-state
amplifiers.
>But ignoring all that, why would anyone want to re-start the whole
>filament cycle if the power line just faulted for a few seconds?
>
If the warmup delay is not re-started, the solution becomes somewhat more
complex. How are we to know what percentage of under-voltage for X
seconds requires Y seconds of makeup preheat?. The safest, simplist
thing is to initiate a restart.
>Cathode temperature would drop at the nearly the same rate as it
>takes to rise. If the line totally removed voltage for ten seconds,
>it would only require a ten second warm up to be back at full
>temperature.
Perhaps. Perhaps not. There is nothing in the Eimac specs. about this
matter. Better to be safe than sorry, methinks.
- My solution (at HF) is to select a tube with an instant-on thoriated
tungsten filament/cathode instead of a tube with a heater and oxide
cathode.
- Rich -
R. L. Measures, 805-386-3734, AG6K
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