Amps
[Top] [All Lists]

Re: [Amps] Clean -vs- Unclean

To: amps@contesting.com
Subject: Re: [Amps] Clean -vs- Unclean
From: Steve Thompson <g8gsq@eltac.co.uk>
Date: Mon, 09 Jan 2006 18:55:19 +0000
List-post: <mailto:amps@contesting.com>

Tom Cathey wrote:
> Here's a coincidence!
> 
> I just received an email from a buddy who is considering buying an 
> FT-1000MP. They are being closed out and discontinued according to a 
> salesman.
> 
> Here's the salesman's comments about the class A stage. This was written by 
> my buddy based upon his conversation:
> 
> "The MP Mark 5's are being closed out by XXX at $XXXX. [I deleted the X 
> info]  The salesman, a DXer/contester said it is being discontinued. The 
> class A amp capability proved to be a negative. If you can believe this, it 
> allowed others to "nustle" in too close to you if your IMD was that far down 
> and make your RXing difficult if not impossible. You need some artifacts to 
> hold others at bay!"
> 
> 
> I won't even comment on that one... [gag - cough]
I'd often wondered about modifying our contest exciter to provide an 
additional path round the narrow filter after the rf processing - 
putting the cliped signal through a 15kHz filter and injecting some back 
into the tx strip downstream. That way you don't have to wipe out the 
whole band to keep clear air. I never got round to trying it.

Far more fun would be something based around the modern DSP/linearised 
feedback transmitters where (in theory) you can have full control of 
your splatter spectrum, and make it adapt to the situation.

Something I still want to try (one day...) is DSP on rx, where a wider 
band rx looks for signals that correlate with the crud in your wanted 
passband, and use that to cancel it out.

Steve
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps

<Prev in Thread] Current Thread [Next in Thread>