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Chris
Had a look around Wikipedia , re phase ,
-3 db , margins , that sort of thing ..as for removing bits ... would
not be the first person to run into allsorts of problems
getting a (137k ) amp to run on 500 'with' half the bits
chopped out ..and still zapp the out put devices
... easier to agree with
MAL
(apart from the class d/e bit that is I think
there is still a lot of un-known's /gray noise etc associated with
the concept .. articles like this seem to address the 'un
spoken' > http://www.qsl.net/wm5z/qex199907.pdf <
the subject of heat dissipation in magnetic's hovers in the background as well
for these amplifiers)
G ..
Sent: Sunday, October 18, 2009 2:13 PM
Subject: LF: AF Amps at 136
Hi All,
Just started constructing TX for 136kHz, noticed
Maplin do a Velleman audio PA kit that is rated at 200W (100W RMS into 4R). OK
there's no mains transformer or heat sink, but reckon it's good value at £14.99.
Point is the specs also say the minus 3db frequency response is 3Hz /
200kHz.
The RSGB books 'LF Today' refer to using audio amps
as PAs at 136 with 'a few modifications'. Does anybody know where these
modifications are documented? I guess there's nothing major, reduce a few cap
values? Remove Zobel Network etc.?? If anyone has experience with this approach
I would appreciate some hints. Thanks.
Chris, G4AYT, Whitstable.
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