I Wonder....

[SOTS 87 7]

I wonder if this might be ok for medium wave. Just a thought.

HF Amp.jpg

[Albert H]

If it's designed to do "Top Band" - 1.8MHz / 160m, then it should work at the top end of the medium wave.

My very first transmitter was a Practical Wireless 1965 AM 807-based top band job. I put a few more turns on most of the coils, and it went down to the top end of the MW. I had a lot of fun with that rig, connected to an inverted-V aerial and a buried galvanised dustbin for the earth!

[SOTS 87 7]

I had a feeling it might, the specs say between 3 - 30Mhz. Seems incredibly wide band to me.
I've got one assembled so maybe I'll give it a try.

[Albert H]

It's a bit high if it's designed for 3MHz upwards. The gain at MW will be much lower, and it might tend to prefer to amplify the harmonics of the driver!

[SOTS 87 7]

Mmm, yes indeed. There doesn't appear to be any kind of filtering on it either which is a tad scary but I'll give it a shot. What's the worst that can happen

[Albert H]

Are you going to try it as a linear? If you're using low level mod, you might want to consider a bit of envelope feedback to clean up the audio somewhat.

[SOTS 87 7]

The intentions were to, yes. But now you come to mention it I seem to remember from the days of AM CB radio the audio always seemed to get more scruffy the more power you put out.
Thanks for the advice Albert, I will give that a go.