I really wish that information would disappear, but the Internet is
forever...
Barry and other's -- Please be careful with this set-up. I was part of the
original discussion back in 1998 together with Terry, W6RU. The concept
looks great on paper, but results in hot-switching on the trailing RF
envelope with some Alpha amps. I detected the problem when the Jennings
RJ-1A failed in my Alpha 77Dx.
The *only* way to proceed using the "Y" adapter requires scope monitoring of
the keyed envelope to ensure proper system timing. For those folks who
don't own an oscilloscope, it may be possible to monitor the keying
sidebands with a panadapter as the hot-switching will show up as excessive
keying bandwidth.
I've said it before and I'll repeat it again. The best way to handle the
switching from the early Ten Tec's into most non-Ten Tec QSK amps is to
sample Ten Tec's "T" voltage and buffer it with an open-collector or MOSFET
device. If anyone needs assistance with this, let me know by private
E-mail.
Paul, W9AC
----- Original Message -----
From: "Barry N1EU" <barry.n1eu@gmail.com>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Tuesday, December 06, 2011 10:05 AM
Subject: Re: [TenTec] Omni-VI QSK with Alpha 87A
Oops, I think I found the info on the Alpha forum. I will add it to
the Ten-Tec Wiki. If anybody has tried this with an Acom 2000A or
Alpha 99, please drop me a line.
73, Barry N1EU
-------------------------------
Omni-VI, Omni-VI+ (maybe others):
Make up a cable with a diode in series to connect the 87A "relay" line
to a "Y" that plugs into the "TX OUT" and "TX EN" jacks on the
Omni-VI. The "TX OUT" and "TX EN" are connected together by the "Y",
the diode connects to the center conductor of the third leg of the
"Y". The polarity of the diode has the cathode (band end) connected to
the Y, diode anode goes to RELAY jack of Alpha. This will allow the
TenTec "TX OUT" signal to key the amp when it enables the radio for
transmit. This works on both CW QSK and SSB. DO NOT do this with any
other amplifier unless you know that the keying line polarity of the
amplifier is correct AND that the amp keying circuit is of very small
current. This is only recommended for use with a Alpha 87A or 89 (they
use PIN diodes for fast T/R switching). Thanks to Terry W6RU for this
circuit (posted on the TenTec reflector).
All other radio/amp combinations, use the amplifier keying relay in
the radio to the RCA jack on back of amp labeled RELAY.
On Tue, Dec 6, 2011 at 10:02 AM, Barry N1EU <barry.n1eu@gmail.com> wrote:
Does anybody have the information that was contained in the post that
W4PA mentions below? That link doesn't work any longer.
Thanks & 73,
Barry N1EU
---------------------------------------------------------------------
[CQ-Contest] Re: Omni-VI QSK with Alpha 87A
from [Ten-Tec, Inc. Amateur Radio Sales]
Subject: [CQ-Contest] Re: Omni-VI QSK with Alpha 87A
From: sales@tentec.com (Ten-Tec, Inc. Amateur Radio Sales)
Date: Wed Apr 7 12:02:46 1999
Hi John W0UN (and all):
The Omni-VI and Omni-VI Plus will run QSK CW very nicely with
the Alpha 87A. The normally open relay jack that is used for
keying an external linear amplifier in the Omni-VI was designed
for non-QSK amplifier use and isn't really optimal for QSK.
Rather than repeat what's been posted elsewhere before, do a
browser point to:
<http://www.contesting.com/_tentec/9809/0383.html>
This very simple hookup uses a pickoff on the Omni-VI QSK
keying loop through a diode to the Alpha 87A input that will
provide both with smooth QSK keying.
73,
Scott Robbins, W4PA
Amateur Radio Product Manager, Ten-Tec, Inc.
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