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[RFI] Nearby ham overload

To: <rfi@contesting.com>
Subject: [RFI] Nearby ham overload
From: wa3gin@erols.com (David Jordan)
Date: Sun, 22 Sep 2002 20:15:21 -0400
HI,

You can limit the overload by increasing the selectivity of your 
receiver front end.

One way to do that is to turn off the pre-amp on the PRO.  

In addition to that you can introduce a high-Q tuned circuit in series 
with your front-end.  A good matching network like the Heath Kit tuner 
SA2060 or similar will provide you with the additional attenuation on 
the sides of your selected frequency.  To optimize the "Q" you will have 
to use the maximum amount of inductor.  You'll have to take into 
consideration the power you run...HI-Q means high voltage on those air 
variable capacitors. If you run high power you may have to lower the "Q" 
in the tuner.

You can also spend a few hundred bucks on an ICE contest passband filter 
which will also help a bit but I prefer the external tuner because you 
can really tweek it.


You should also get your neighborhood ham buddy to do the same thing on 
his end.  Ensure both internal tuners are active at the very least.

The FT1000 uses cascaded filters and puts out a very clean signal. 
 You're dealing with front-end over load.  

I had a neighbor ham so close I could see his beam from my tower.  We 
used his station to tune my home brew quad elements. SO, I know these 
recommendations work because I've used them all.

Best of Luck,
dave
wa3gin



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