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Re: false signals-images-harmonics-whatever? FIXED !!



Hi Greg,

Coax type was RG-58, I chose that because it would be easier to clip a
little piece off.  I tried to cut 1/8 inch each time and yes length is
critical.  Not much happens until you get close to resonance then I trimmed
as little as I could until the signal dissapeared.  I did not measure
resulting length, I think the point is you need to work up to it yourself,
it is not a one cut deal. Sealed it with RTV silicone glue.  Coax-Seal would
work also.

73's Tracy

----- Original Message -----
From: "Greg D." <ko6th_greg@hotmail.com>
To: <k7kcs@attbi.com>
Sent: Friday, January 04, 2002 8:29 PM
Subject: Re: [amsat-bb] false signals-images-harmonics-whatever? FIXED !!


> Hi Tracy,
>
> Sounds like my problem; I can't hardly hear myself when I key up,
> because the noise floor jumps so high.  Just curious - what type
> of coax did you hang off the Tee, and how long did it end up being?
> How much did you cut each time?  The length sounds critical.  Did
> you seal it afterwards to keep out the weather?
>
> Thanks and 73s,
>
> Greg.
>
>
>
> >From: "Tracy" <k7kcs@attbi.com>
> >To: <amsat-bb@AMSAT.Org>
> >Subject: Re: [amsat-bb] false signals-images-harmonics-whatever? FIXED !!
> >Date: Fri, 4 Jan 2002 17:53:57 -0800
> >
> >Hi all,
> >
> >Thought I'd share the results of all the suggestions I got on how to get
> >rid
> >of the images my uplink (435 Mhz) was creating in my downlink passband
(2.4
> >Ghz).
> >
> >1.  The images were indeed stronger when antennas pointed at neghbors
> >house.
> >2.  I disconnected helix and hooked in a dummy load; images dissapeared.
> >3.  I turned off DC to downconverter; images dissapeared.
> >
> >I was ready to buy a notch filter or a better D/C but K5OE gave me a
> >suggestion I had to try first.
> >
> >1.  I installed a coax "T" off the helix and connected a 5 1/2" coax stub
> >off the extra end of the "T".
> >2.  I monitored the image signal strength while trimming little pieces
off
> >the coax stub.
> >3.  After about 20 cuts, the image became inaudible.
> >
> >Problem solved . . total cost $13.00 for the "T"
> >
> >Thanks to all who made suggestions.
> >73's
> >
> >----
> >Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> >To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
>
>
>
>
> _________________________________________________________________
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http://explorer.msn.com/intl.asp.
>

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