Eric,
I don't know what permeability your beads have. Normally used "EMI" beads
run around 850, with 100 to 200 ohms added impedance (each)**at 100 MHz**.
You can expect them to have very little effect at 160 or 80 meters. Note
that the Wireman 2500 mu ferrites are only three times as high, so will not
be much better that low in the spectrum.
Why not see how it works without adding beads after the transformer, or if
there ARE common-mode problems, try an old flyback transformer core (mucho
mu) with a number of turns of coax wrapped through it?
Cortland
> [Original Message]
> From: Eric Rosenberg <wd3q@erols.com>
> To: <towertalk@contesting.com>
> Cc: <rfi@contesting.com>
To: <towertalk@contesting.com>
> Date: 6/24/2002 10:42:15 AM
> Subject: [RFI] Choke Balun on RG-59 Coax?
>
>
> I'm going to feed my new 80/160 EWE's with RG-59 (have LOTS of
> it!) and want to put choke baluns at the feedpoint.
>
> I have the Wireman kits and QST article, but would rather put
> the ferrites directly on the feedline.
>
> The question: how many beads do I need (considering that RG-59
> isn't the same as the RG-303 that is called for in the article),
> and what size.
>
> Thanks in advance,
>
> Eric W3DQ
> Washington, DC
>
>
>
>
> _______________________________________________
> RFI mailing list
> RFI@contesting.com
> http://lists.contesting.com/mailman/listinfo/rfi
--- Cortland Richmond
--- ka5s@earthlink.net
--- EarthLink: The #1 provider of the Real Internet.
|