I Wonder....

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SOTS 87 7
no manz can test innit
no manz can test innit
Posts: 165
Joined: Tue Sep 16, 2014 10:20 pm

I Wonder....

Post by SOTS 87 7 » Fri Aug 30, 2019 8:53 pm

I wonder if this might be ok for medium wave. Just a thought.
HF Amp.jpg
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Albert H
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Re: I Wonder....

Post by Albert H » Fri Aug 30, 2019 10:56 pm

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!
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

SOTS 87 7
no manz can test innit
no manz can test innit
Posts: 165
Joined: Tue Sep 16, 2014 10:20 pm

Re: I Wonder....

Post by SOTS 87 7 » Sat Aug 31, 2019 12:16 am

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
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Re: I Wonder....

Post by Albert H » Sun Sep 01, 2019 12:27 pm

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!
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

SOTS 87 7
no manz can test innit
no manz can test innit
Posts: 165
Joined: Tue Sep 16, 2014 10:20 pm

Re: I Wonder....

Post by SOTS 87 7 » Sun Sep 01, 2019 11:05 pm

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 :lol:

Albert H
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Re: I Wonder....

Post by Albert H » Sun Sep 01, 2019 11:21 pm

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.
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

SOTS 87 7
no manz can test innit
no manz can test innit
Posts: 165
Joined: Tue Sep 16, 2014 10:20 pm

Re: I Wonder....

Post by SOTS 87 7 » Mon Sep 02, 2019 7:07 pm

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.

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