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Fw: Replacement KLM 2M-14C matching harness coax?

----- Original Message -----
From: "Ken Swaggart" <k.swaggart@charter.net>
To: "AMSAT-BB" <amsat-bb@amsat.org>
Sent: Wednesday, March 19, 2008 12:49 AM
Subject: [amsat-bb] Replacement KLM 2M-14C matching harness coax?

> It's time to rebuild my Oscar 10 vintage KLM 2M-14C matching harness.
> are no markings on the original harness but it has teflon insulation and I
> assume it is 75 Ohm. Anyone have the replacement info? I'd prefer to use
> teflon cable. The antenna manual doesn't describe the matching harness.
> Tnx,
> Ken, W7KKE
Hi Ken, W7KKE

The balun across each folded dipole is made with 50 ohm RG-303 teflon
insulated coax cable, velocity factor 0.694

The phasing coupling harness is made with two matching lines of 75 ohm
RG-302 teflon insulated coax cable, velocity factor 0.694

The polarity switcher is a relay Guardian Electric WJ MFG Corp 1365 series
12 V dc A410-364385-00

Due of the lenght of relay the lenght of coax RG-302 going from relay to the
50 ohm unbalance feed is critical to be 1/4 electrical wave long beginning
from the folded dipole so that use only 75 ohm RG-302 or any other type
of 75 ohm teflon insulated coax with the same lenght as the original one.

For water protection it is necessary to enclose the PCB and relay into an
additional plastic box and if anyone is interested on it I can send a set of
pics showing my own installation.

73" de

i8CVS Domenico

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