[Amps] Centurion cooling improvement ideas for AM service

[Rob Atkinson, K5UJ]

thanks Will, for the IR thermometer info.

<<<However, they do take the carrier into more consideration
than the modulated power due to the duty cycle. The transformer is
supposed to be able to sustain the carrier without putting any real drag
on it. That is for any amp that is AM-CW capable. I was under the
assumption they are all still made this way today as I don't recall
seeing any commercial SSB only tube amps (unless homebrew). I might be
wrong but I notice they're CW capable on all the advertisements. One
thing about it though, if those AM conversations were that long (20
min), a very long SSB broadcast shouldn't be any sort of a problem!
Wonder what rig and amp they were running?>>>

I think the CW specs for most amateur linear amps assume a 50% d.c.
for the limit on keydown you have to find the spec. for RTTY and with some
exceptions, there will be a time/power limit.

AM isn't so simple, and there are some paradoxes for those familiar with SSB 
operation only.
One is that an amp in AM service actually runs cooler when the driving 
carrier is modulated and the
amp is boosting sidebands and the carrier; it runs a bit hotter when you are 
not saying anything and it's keyed and txing carrier only.  since it's tuned 
for 4x carrier power, efficiency is higher and heat dissipation less when 
getting full voice.  So, don't shut up!  Dead air = meltdown hi hi.

Rob/K5UJ

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