Thanks for the post, Paul. If you have any pics of that Omni VII mod,
please send them along to me. And Ron......NO need for any defense on your
part. A perfectly reasonable expectation.
73 John K4NP
----- Original Message -----
From: "Paul Christensen" <w9ac@arrl.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Sunday, December 09, 2007 9:18 AM
Subject: Re: [TenTec] OMNI VII QSK users with good ears....
I'm trying to think of a modern Ten-Tec radio that doesn't use a relay
for
T/R switching, and can't think of one!
Their reed relays are plenty fast enough and I see no real benefit over
PIN
diode switching except for longevity. Still, few relays fail in these
rigs
even after 20+ years.
I did replace the T/R relay in my Omni VII with a Matsushita/Aromat RS-12D
reed relay, made specifically for RF switching. While the stock Omni VII
relay is reasonably quiet, it's possible to take the slight ticking noise
to
zero with the RS-12D.
Ten Tec used an ingenious scheme to isolate the T/R relay. They mounted
it
on a very small PCB and cushioned it with foam. I took their idea a step
further and replaced the solid conductor wire with ultra-fine strand,
silicone jacketed wire from a robotics company.
http://www.trossenrobotics.com/store/p/5224-22AWG-High-Strand-Count-Silicone-Wire-Combo-Pack-25-ft-.aspx
The new wire is super flexible and does not acoustically transmit the
armature noise back to the PCB. Totally silent QSK now even when placing
the ear on the cabinet.
Paul, W9AC
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
--
No virus found in this incoming message.
Checked by AVG Free Edition.
Version: 7.5.503 / Virus Database: 269.16.15/1174 - Release Date:
12/6/2007 10:11 AM
|