Hi Lyle--
I am he who said "with key up." Here's what happened to me. I came up on
18 MHz and when I turned from Tune to CW, the rig was still putting out
about 1.5 watts. Key down it was putting out over 50, I didn't turn the
drive all the way up. All these oscillators are running whether the key is
up or down.
Running tests with that rig and another receiver, I found that there was a
big spur that changed frequency as I changed my PTO setting. Dim memory
(I've slept since then) is that the crystal oscillator for the 18 MHz band
was adding to the PTO frequency and that was then producing a second
harmonic that was coupling right back out through the driver and amplifier.
Further, I noticed that the local oscillator operates on 9 MHz give or take
a little bit depending on whether the rig is on CW or SSB, etc. This local
oscillator also has a second harmonic that gets transmitted. In addition,
the mix of the PTO, the band crystal and the local oscillator can also
produce a signal, I think.
I was just horrified. Right away (next morning) I phoned Ten-Tec and told
Garland Jenkins of my observations. As I recall (remember I've slept since
then), his response was, "Yep, they'll do that." I asked him if there was a
fix and he said that if I wanted to work 18 MHz, then I ought to get a
different rig. Truth be told, I did get a different rig and a different rig
and a different rig, but not to work 18 MHz.
The WARC bands are a work of the Devil in my opinion. It is as if some evil
person was trying to destroy amateur radio and said, "if we give them enough
spectrum, they will be so spread out that they will never hear each other,
will get discouraged and quit."
73,
Mike N4NT
----- Original Message -----
From: "Lyle Dunlap" <lyle3dd@grics.net>
To: "Mike Hyder -N4NT-" <Mike_N4NT@charter.net>
Sent: Friday, April 14, 2006 8:34 PM
Subject: Re: [TenTec] Omni C self-test
OK Mike maybe I missed something along the line. I understand about 2nd
harmonic from 9mc. But someone said with key "UP"
I do not take much notice of the reflector these days with all the orion
crap gong on.
Lyle FCX
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