As an alternative to coax, try using twisted pair - pull a couple pairs
out of a short length of CAT-5 cable. One of the pair would be grounded
at each end (will require adding a solder lug at the SO-239 jack).
73,
Don W3FPR
Stewart Baker wrote:
David,
A very good point. Although the space is rather restricted for
RG58/U it should be possible to fit some of the smaller diameter
cable such as that used to connect between VHF/UHF PCB's.
I have some silver braided coax that would be suitable.
It would have little adverse effect over such a small length, but
might provide additional isolation.
Food for thought...
73
Stewart G3RXQ
On Wed, 16 Jul 2008 12:14:03 -0400, David Robertson wrote:
Stewart,
Your posting is good information however one of the factors of
isolation between ANT 1
and 2 can be how the pigtail leads from the 2
SO239 connectors and the antenna coupler board are dressed. It
would seem easy to have
these nonshielded wires crossing or near each other. The space
seems too tight to use
rg58/U cable. this could mean that depending how those wires
were dressed the coupling
would be different between all K3's.
73
Dave KD1NA
From: Stewart Baker <[EMAIL PROTECTED]>
Subject: Re: [Elecraft] Re: KAT3 ATU and SPE Expert 1K-FA
Amplifier
To: Dave G4AON <[EMAIL PROTECTED]>,
<[email protected]>
Message-ID: <[EMAIL PROTECTED]>
Content-Type: text/plain; charset="ISO-8859-1"
I made some measurements of the isolation between ANT 1 & ANT 2
on
my K3.
There is little difference between ATU & BYPASS. Unable to do
50MHz.
1.9MHz 58.1dB
3.7MHz 51.9dB
5.1MHz 49.2dB
7.0MHz 47.1dB
10MHz 44.7dB
14MHz 42.5dB
18MHz 40.8dB
21MHz 39.2dB
24MHz 37.1dB
28MHz 35.7dB
So on 60m for 100W from ANT 1 there will be 1mW from ANT 2.
73
Stewart G3RXQ
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
No virus found in this incoming message.
Checked by AVG - http://www.avg.com
Version: 8.0.138 / Virus Database: 270.5.0/1555 - Release Date: 7/16/2008 6:43 AM
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
