BBC Programs Heard on DC-area FM stations.
 

m II wrote:
I was under the impression that most commercial transmitters used tubes.
I don't think a couple of 2n2222 transistors could handle a 50 KW output.

Nobody makes a 50kw transistor, but 200 250-watt transistors in
push-pull-parallel will do the trick. Solid-state 50kw transmitters are
by no means unusual. They're also a lot more reliable than tube rigs.

We have a solid-state 6kw digital TV transmitter at work. It's amusing
to pull out two or three power amp modules and see *absolutely nothing*
happen -- the power meter doesn't even drop -- all that happens is you
get an alarm on the control panel warning of the missing modules...
--
Doug Smith W9WI
Pleasant View (Nashville), TN EM66
http://www.w9wi.com

BBC Programs Heard on DC-area FM stations.
 

Doug Smith W9WI wrote:
m II wrote:
I was under the impression that most commercial transmitters used tubes.
I don't think a couple of 2n2222 transistors could handle a 50 KW output.

Nobody makes a 50kw transistor, but 200 250-watt transistors in
push-pull-parallel will do the trick. Solid-state 50kw transmitters are
by no means unusual. They're also a lot more reliable than tube rigs.

We have a solid-state 6kw digital TV transmitter at work. It's amusing
to pull out two or three power amp modules and see *absolutely nothing*
happen -- the power meter doesn't even drop -- all that happens is you
get an alarm on the control panel warning of the missing modules...


Neat. It's like a redundant array setup for hard drives.




mike

BBC Programs Heard on DC-area FM stations.
 

On Tue, 21 Mar 2006 02:31:24 GMT, m II wrote:

Doug Smith W9WI wrote:
m II wrote:
I was under the impression that most commercial transmitters used tubes.
I don't think a couple of 2n2222 transistors could handle a 50 KW output.

Nobody makes a 50kw transistor, but 200 250-watt transistors in
push-pull-parallel will do the trick. Solid-state 50kw transmitters are
by no means unusual. They're also a lot more reliable than tube rigs.

We have a solid-state 6kw digital TV transmitter at work. It's amusing
to pull out two or three power amp modules and see *absolutely nothing*
happen -- the power meter doesn't even drop -- all that happens is you
get an alarm on the control panel warning of the missing modules...


Neat. It's like a redundant array setup for hard drives.




mike
Sort of. The distortion goes up and the remaining devices are put
under extra strain.