160m, maybe 80m also - AM Transmitter

[N1LAF]

Following link is to a 200 AM class E transmitter, modifiable to 160m, and maybe 80m...

http://www.maxmcarter.com/classexmtr/circuitdescription.php

Could be the basis of a project.

The article talks about using PA amplifier as modulation input - which is an intriguing idea.

Watch out George, Mr 'AMR, AM transmitter project may add to the AM ranks.

[NQ6U]

Bet it doesn't sound as nice as a plate modulated tube rig, but it looks interesting and doable. It does have distinct advantage of not requiring that you mess around with high voltage DC.

[n2ize]

Bet it doesn't sound as nice as a plate modulated tube rig

A few of the New England AM Gansta's are running class E rigs and they sound damned good. Nice clean audio, no distortion , nice frequency response, etc. They sound as good or better than some of the better quality home brew plate modulated rigs and way way way better than an unmodified commercial plate modulated ham rig. Most of the old plate modulated commercial ham boatanchors were designed to pass narrow communications quality audio. When you "open up" the audio chain to allow a wider frequency response you often end up with anything but a nice clean response from low end to high end. There are several "fixes" for these problems including adding some negative feedback, filtering, right on up to solid stating the power supplies, using a different type of modulator tubes and mod transformer. One little trick some of the guys would do with the Viking 2's was to tie the grids of the 807 modulators together run at zero bias and run the 807's as tetrodes. Or, to pull the 807's out altogether, change the sockets and run a pair of 811's instead.


Timtron/WA1HLR is famous for his bag of tricks when it came to making a boatanchor sound respectable.


, but it looks interesting and doable. It does have distinct advantage of not requiring that you mess around with high voltage DC.[/QUOTE]

[n2ize]

Following link is to a 200 AM class E transmitter, modifiable to 160m, and maybe 80m...

http://www.maxmcarter.com/classexmtr/circuitdescription.php

Could be the basis of a project.

The article talks about using PA amplifier as modulation input - which is an intriguing idea.

Watch out George, Mr 'AMR, AM transmitter project may add to the AM ranks.

Paul, ever take a look at Steve / WA1QIX's class E site ? He was some interesting designs for class E rigs.

http://www.classeradio.com/

[PA5COR]

Just had a lecture here at our local ham radio club about commercial Radio Waddenzee and the us of a class E audio amp as modulator, and it works fine, listening to it now and then here.
Commercial Class E amps were used 2 x 1000 watts for the price of 300 euro's including internal power supply.... cheap as chips.
Driving a Fet amp as P.A. for 1000 watts R.F. output.