[CQ-Contest] I've heard it all now!

[Glenn VA3DX]

Shame here Bill, I am still in the SHAME file.

John VE3EJ helped me out  with his analyzer and
my harmonic is gone completely with the stub.

I can run a KW now and a friend  who is a 1/4 mile
away can hear nil there now ...

Glenn VA3DX

----- Original Message ----- 
From: "Bill Tippett" <btippett at alum.mit.edu>
To: <cq-contest at contesting.com>
Sent: Wednesday, December 10, 2008 8:31 AM
Subject: Re: [CQ-Contest] I've heard it all now!


>
>
>         I was one of the stations on W4ZT's 3655 Wall of Shame
> list.  The only problem I have with his list is that it appears you
> remain on it forever...even after you fix your harmonic.  Here's how
> I fixed mine with a shorted stub made of ~89' of polyethylene RG-8 (Vf = 
> 0.66).
>
>                                 73,  Bill  W4ZV
>
> "Raoul Coetzee" <raoulc at smmcape.co.za> wrote:
>
> > I am having a bit pf a problem with a second harmonic when
> operating on 160m.
> > This is of course falling in the 80m band segment and causing mild
> to severe
> > qrm to my local 80m friends on phone.
>
>         I had a similar problem when we gained SSB access to 3600 and
> above.  My solution was a shorted 1/4 wave stub for 160 at the output
> of my amplifier.  Use (246/1.83)*Vf to determine the length in feet
> and cut it a little longer if you aren't certain of the velocity
> factor of your coax.  I used an MFJ-259B analyzer and pruned the stub
> for minimum impedance at 3.650.  Just remember to switch out the stub
> for other bands!
>
>         I had reports that my harmonic was S7 before I did this.
> Afterwards I had W0FLS check it using his 4-Squares on both 80 and
> 160.  On 160 I was S9+30 and on 80 I was inaudible, and I've not
> received further complaints from anyone.
>
>                                        73,  Bill  W4ZV
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>
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