Re: LF: FET RDS

[Minto Witteveen <minto.witteveen@gmail.com>]

Hi Stefan,

Thanks for the reference. Interesting schematics, but it is used to produce 
amplitude modulation. Feeding it PSK31 @ 500 KHz from the soundcard isn't 
going to get me very popular I suppose.. I am not sure how this design can 
be used to produce SSB with high(er) efficiency.
Regards,
Minto pa3bca

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From: "Stefan Schäfer" <schaefer@iup.uni-heidelberg.de>
Sent: Thursday, January 13, 2011 23:27
To: <rsgb_lf_group@blacksheep.org>
Subject: Re: LF: FET RDS

<snip>
> > My original 500 KHz design was for linear operation (so I could use 
> > psk31) but I only made one qso in PSK, the rest in ordinary CW. A new 
> > design can and will be much simpler.
> Have you heared about a class H modulator? This is a circuit that 
> separates AM and FM. The FM and PA can be done by a class E design and the 
> AM is applied by modulating the supply voltage by a step down converter 
> (the class H modulator). I've never built one but there are some 
> interesting examples at http://www.classeradio.com/classh.htm
> This would be a good combination to push-up a class E PA for linear mode. 
> Since i do nothing more than CW/QRSS/DFCW i actually do not need one ;-)
<snip>