Hi Andy.
A simple L C L circuit as described in the Solid State Design for Radio
Amatuers Book, but I made the 'C' variable so I can tune it up in a similar
manner to that of PI tank circuit. I dont have any CAD for diagrams, all
the pcb artwork was done by hand, I had a bit of techniacl smoke with the
first PA a few dead power MOSFETS on the shack floor, but a chat with Chris
G3XIZ and it was sorted out. Technical writing is ok as I used to write
technical specifications and technical trial reports at BT.
73
Ken M0KHW
----- Original Message -----
From: "Andy Talbot" <[email protected]>
To: <[email protected]>
Sent: Sunday, July 20, 2008 6:44 PM
Subject: Re: LF: Re: LF RadCom Articles
Send it in - sounds just like the sort of simple 'weekend' article
several technical editors have been asking for.
btw. By LCL output stage, assume you mean a lowpass Tee network?
Andy G4JNT
www.scrbg.org/g4jnt
design
and build our own equipment, but do not submit it for possible
publication
because, state of the art technology it is not, the design is not
particularly elegant, and the Technical Editor and the more accomplished
contributors would fall over laughing when they saw it. But most of these
projects are practical and they work. I work on the KISS (Keep It Simple
Stupid) principle, don't use three components when one will work just as
well. My 500kHz TX does not have any fancy CW sidetone circuit on
transmit,
just a piezo buzzer wired across the keyed 12v line to the driver board,
the
most complicated bit is the LCL output stage, which delivers 23W into a
50ohm dummy load and 900mA up the antenna, the TX/RX switching is like
the
old days, a simple toggle switch.
--
|
