I know a guy who works at one of the 50 kw clear channel MW stations in
Chicago and they went to a solid state transmitter at some point in the
past. You can go to the Harris website and look at them--they have them up
to 500 kw if I remember correctly, for MW and HF (also FM and low power TV).
They consist of a power supply, a bunch of rf modules, each producing a
few kw which can be hot switched, a digital modulator and a matching circuit
to the hard line. I guess broadcasters are going to these because of the
reliability and even though they might cost more up front (I'm assuming they
do) there is a lot of cost recovery since they don't need to staff the tx
site, and the light bill is lower.
Obviously the economic factors for hams are totally different--we're not
making money off our stations after all--so linears sold to us have to be
reasonably affordable (or what passes for that these days). So far the ss
linears I've seen are 1 kw and pretty pricey on the buck per watt scale.
I'm wondering if the wise men on this reflector would care to venture a
guess as to how long it will be before someone can make and sell a 1.5 kw
solid state hf linear, that will go 100% no time limit, that's priced the
same as a tube amp that can do the same thing? Is it ever gonna happen?
What are the technical problems? Should someone about to buy an Alpha, QRO
etc. hold off and wait (not me; purely hypothetical)? Or are 1.5 kw hams
going to be firing up cathodes for some time to come? Just wondering what
you all think about this.
73,
Rob Atkinson
K5UJ
k5uj@hotmail.com
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.
|