Re: High Voltage Components from microwave ovens

From: Paul Keinanen (keinanen_at_sci.fi)
Date: 06/26/04 

Date: Sat, 26 Jun 2004 12:56:45 +0300

On Fri, 25 Jun 2004 23:28:12 -0000, dplatt@radagast.org (Dave Platt)
wrote:

>According to a talk I saw recently, commercial television broadcasters
>have moved almost exclusively to solid-state RF amplifiers for their
>newer stations. No one set of transistors can provide thenecessary
>power, so the amps use a large number of smaller modular amplifiers
>operating in parallel - I think the basic "brick" we were shown was
>capable of a couple of hundred watts. I haven't seen any ham-band
>amplifiers using this modules-in-parallel approach, although I'm
>sure one could be built.

In broadcasting, the station is usually operating on the same
frequency all the time, so simple Wilkinson dividers/combiners (which
are frequency specific) can be used, which effectively isolates the
modules from each other, when one module fails.

However, a ham linear amplifier is typically required to operate in
the 1.8-30 (or -54) MHz frequency range, which complicates the
divider/combiner issue.

Paul OH3LWR