[Elecraft] KAT-500 interface cable question

[kd4iz at frawg.org]

Clint,

I looked at that as a possibility, did a cursory look at an MFJ auto-tuner schematic, then decided that it was too easy to make one with spare parts and heat shrink. I would hate to spend $20 plus shipping - only to have to cut off the heat shrink on the MFJ cable, disassemble, do surgery to replace the Molex, and put on new heat shrink if I chose poorly.

Using the home brew cable, my 7300 and 7100 both work well with the KAT500 which I use with a KPA500. Next projects will be to make a patching switch to pop between the two for when I do simplex DV on HF.

I have not tried to use my KX3 with the KPA/KAT500 combo, but assume it would be easy.

KD4IZ
Jack Spitznagel
FM19oo



-----Original Message-----
From: Don Wilhelm <donwilh at embarqmail.com>
Sent: Friday, November 2, 2018 11:11
To: Clint Talmadge <clinttalmadge at gmail.com>; elecraft at mailman.qth.net
Subject: Re: [Elecraft] KAT-500 interface cable question

The wiring for the Icom AH4 Interface is detailed on page 8 of the
KAT500 manual.  Pin 4 of the Molex connector is connected to the shield
(shell) of the T-R-S plug.

I don't know how the MFJ cable is wired.

BTW - there are no hyphens in Elecraft product designations, so it is the "KAT500" and not the "KAT-500".

73,
Don W3FPR

On 11/2/2018 10:45 AM, Clint Talmadge wrote:
> New guy here with a question. I am about to get a KAT-500 to mate to 
> my IC-7300. In searching for the Molex connector I need to make an 
> interface cable for the radio to the tuner, I came across the 
> MFJ-5124I cable which MFJ sells to mate their 99* series auto-tuners 
> to Icom radios. The connectors on the tuner end are the same as used 
> on the KAT-500. The wiring is the same with one addition. Where there 
> is no ground connection from the sleeve of the 3.5MM stereo plug 
> specified in the KAT-500 manual, the MFJ cable has the sleeve connected to the ground pin of the Icom connector.
> Seeing the that the sleeve of the 3.5mm stereo connector on the
> KAT-500 is chassis grounded anyway I think I can use the MFJ cable to 
> interface my
> KAT-500 to my IC-7300.  Does anyone see the flaw in my thinking? 
> (about the cable, not the radio) de W5CPT