[Antennas] Re: B&W window antenna

[Dan Richardson]

Why oh why do so many judge an antenna by the SWR? No matter what the 
experts say AND PROVE... Still solely judged on SWR?

Danny, K6MHE


At 07:01 PM 4/3/2002 -0500, you wrote:
>Just some of my own input here.
>I had the chance to help a local ham try to get his B&W window antenna to hum.
>We tried everything and the best SWR on 20 meters was 4.1 to 1.
>We then tried a tuner and could not get below 1.7.
>We added grounds and 2 more radials.
>We then tried the 40 meter and the instructions said to leave the wire for
>the tap OFF or hook it at the end of the coil.
>Same problem.
>SWR was better at 3.1 but at least we got it down flat with the tuner.
>But a tuner should not be needed.
>Now my home brew window antennas I had great difficulty finding the sweet
>spot on the coil for a low SWR but I did find it and the SWR was 1.3 and also
>was taken down lower by moving the radial..
>We went back to the B&W and added 2 turns to the coil and we moved the tap
>just short of 1 full turn.
>BINGO!! we had a 2.1 SWR.
>Playing around we got as low as 1.4
>I think I'll keep with my 9 foot job I built the first time.
>Tomorrow B&W gets a call and I want to know why we had to add 2 turns or if
>it was a factory defect.
>I have not seen the MFJ but it has a 4-1 balun built into it but I can't seem
>to get any info on it.
>So if you feel the need for a short antenna and want to work DX build your
>own or just use a mobile stick..
>The coil on my home brew has 50 turns and tapped appx 2.5 turns up from the
>bottom.
>That gives me a flat SWR and I have a full 75 KC on 40 meters and the SWR
>climbs up to 1.3.
>Close but no cigar.
>Remember if you want to build one they work great but the taps are very fussy.
>I used a needle to tap # 18 GA RS speaker wire.
>I has a noise bridge in line and when that started to settle down I put the
>SRW meter in line.
>A lot of fun and you can bag world wide DX with them as many have.
>But B&W in the past had a coil for each band and I feel thats where they
>screwed up.
>I guess as i'm not an EE.
>I just assume.
>As it stands right now i'd rather have a coil for each band.
>Anyone have this problem with the B&W?
>SAVE$$$$$$$$$$$$$$ and build.
>Bob
>AF2Qrp <tm>
>- - -
>
>Your moderator for this list is:
>Larry Wilson KE1HZ antennas-owner@mailman.qth.net
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