[Amps] Even more power solid-state amp's

[Joe Subich, K4IK]

Will writes: 

> I cant figure them using them. One big amp I seen was a 
> cabinet with maybe 100 cards in it. Each card had maybe 2-4 
> push pull amp assemblies on it (or what it looked like to 
> me). When they repair one, they pull out a card or two of the 
> bad ones and put a new one(s) in their place. To me, I'd soon 
> to have 1-2 big steel tubes instead that rats nest of all 
> those cards, but that's the way their wanting to go. 

The TV transmitters typically run 50 KW peak power (Sync & black). 
A few will go to 100 KW, generally with two 50 KW transmitters 
in parallel.  The cards are typically two amplifiers (50 Volt) 
in push-pull/parallel providing about 1600 watts per card and 
there are 32 to 48 cards per cabinet.

The real advantage of the solid state "cards" is soft fail 
capability.  If one transistor is lost power output falls 
3-5%.  If a single tube fails, the station is down to 50% 
power at best.  In addition, the solid state amplifiers can 
be replaced without any need to go off the air. 

73, 

   ... Joe, K4IK