So will my Excel spreadsheet at
http://www.btinternet.com/~alan.melia/classepa.htm#Class%20E%20Power%20Ampli
fier%20Design
I hope there is not too much trouble with the URL folding-back.
Several LF amps have been made from this and at least two for 500kHz.
High supply voltage is preferable as it increases the impedance of the stage
and reduces the currents flowing for a given power level. Sticking my neck
out none of us using single ended ( single or parallel devices) Class-E
stages has ever lost a FET to aerial mismatch, or instability. Over 500
watts has been generated at 60 to 75v.
The only caveat is DONT tune it for maximum smoke, tune for the design power
or maximum efficiency (rf power out/ dc power in.) PAs dont come much
simpler, mine generated 150 watts on the bench lashed up with choc blocks
and croc leads. The efficiency as around 92% from a 35volts supply.
Cheers de Alan G3NYK
----- Original Message -----
From: Johan H. Bodin <[email protected]>
To: <[email protected]>
Sent: 09 March 2007 21:53
Subject: Re: LF: Re: RE: 500 G3WCB QRV 503.500kHz
> Hi Gary,
>
> If I remember correctly, DF3LP's design is "class-C-ish".
> Your FET will probably run cooler if you use a class E
> output network (still with 50/50 squarewave drive).
>
> The program at
> http://www.tonnesoftware.com/classe.html
> will design it for you.
>
> 73
> Johan SM6LKM
>
> Gary - G4WGT wrote:
> > & the DF3LP is the design
>
>
>
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