UHF (70cm) PA
geek wrote:
On Mon, 19 Jan 2009 06:00:45 +0000, Bob wrote:
snip
If I was designing a UHF PA, I'd choose FETs these days!
Alas, if automobiles used 48V instead of 12 ;-)
Cheers!
A lot of stereos have a DC-DC converter to generate a supply voltage like
that for the audio amplifier.
If you do build a DC-DC converter, then at least the output voltage could be
well regulated and free of spikes, unlike an automotive "12V" supply. Of
course quite a bit of shielding and LC filtering of the supply may be
needed to stop the PA supply from having ripple that will cause AM
sidebands on the Tx signal at an offset equal to the switcher frequency.
Chris
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