Thank you for this reply Mike, I appreciate the benefit of this experience.
I have wooden masts so not likely a problem on those... But the SG-230
antenna tuner at the antenna is a likely suspect as well as the wire and
coax connections along the way. The MFJ Deluxe Versa Tuner at the station
termination end is also a possible source of harmonic mixing I think.
Best let the conversation return to headphones and ear pads. :)
Ron KA7U
-----Original Message-----
From: Mike Hyder -N4NT- [mailto:n4nt_m_o_hyder@charter.net]
Sent: Tuesday, January 03, 2006 6:02 AM
To: Ron
Subject: Re: [TenTec] LW receiver - did it sound normal?
Hi, Ron--
I had many images in the 80 meter band. Here was what I found:
Usually, one of them had distorted audio -- much the same as you would
expect if you heard the second harmonic of a SSB signal. Thus tones were
spread out, a 1000 Hz transmitted tone would be heard as 2000, etc. Thus if
you hear the distorted audio, you are hearing a harmonic. This can be an
ordinary sort of harmonic or part of an intermodulation product.
3rd order intermodulation products are the second harmonic of one signal
mixing with the fundamental of another signal. They can be generated in a
transmitter (transmitter intermod), a receiver (receiver intermod) or in any
other mixer. Intermod products generated external to the receiver will come
through regardless of how good the receiver is.
I had a Rohn 25G tower and the guy wires were connected to tower legs with
stainless steel devices in the shape of a long U. After much time spent
trying to find the source of mixing, I discovered that there was apparently
some mixing done at the junction of the stainless steel and the galvanized
tower. Using ground clamp type things, I put jumpers from the tower to each
guy wire. That cured my problem.
Good luck.
73, Mike N4NT
----- Original Message -----
From: "Ron" <ron@morell.us>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Cc: <n4nt_m_o_hyder@charter.net>
Sent: Tuesday, January 03, 2006 1:51 AM
Subject: RE: [TenTec] LW receiver - did it sound normal?
Hello Mike,
For the report of signal at 260 KHz, it was completely normal AM sound music
and all. Did not hear any other station overlaid with it. Loud and clear
with ten over S9 signal.
I heard another today at 3580 KHz on the Main receiver. Found one of the
stations at 1460. This time I could detect another station faintly overlaid
with the main station from 1460 KHz. This signal was still there after
filtering down to 600 Hz with the roofing filters. Curious to me that these
broadcast stations can hetrodyne up into the amateur bands on this ORION II
even with roofing filters and all that to prevent it. I find AM broadcast
stations on 160 and 80 quite regularly... Maybe something is up with my
SG-230 antenna tuner or other anomalies in my antenna system that is
producing these signals and hence the detection of them by the ORION II. No
way the ORION II is going produce these hetrodynes and detect them in the
amateur bands on the main receiever, right?
Ron KA7U
-----Original Message-----
From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com]On Behalf Of Mike Hyder -N4NT-
Sent: Monday, January 02, 2006 6:26 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] LW receiver - did it sound normal?
On the signal you received was the modulation normal sounding or distorted
in some way?
Mike N4NT
----- Original Message -----
From: "Ron" <ron@morell.us>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Cc: <CATFISHTWO@aol.com>
Sent: Sunday, January 01, 2006 8:44 PM
Subject: Re: [TenTec] LW receiver
Tom,
Ineresting idea of two AM broadcast stations producing the signal at 260
KHz, but as I did not hear any signal but the 1160 KHz station there, I
think it is probably a product of the IF mixer. I was using the Sub
Receiver. It was a 10 over S-9 signal at 260 KHz and a 40 over S-9 signal
at 1160 KHz. When I get time, and conditions are similiar and I can tune it
in, I'll hook up my old Tuned Receiver Front End Regenerative (RAK-8)
receiver and see what I hear at 260 KHz. No IF in that old boat anchor.
Thanks for you reply.
Ron KA7U
-----Original Message-----
From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com]On Behalf Of CATFISHTWO@aol.com
Sent: Saturday, December 31, 2005 1:56 PM
To: tentec@contesting.com
Subject: Re: [TenTec] LW receiver
In a message dated 12/31/2005 10:31:52 A.M. Pacific Standard Time,
ron@morell.us writes:
Listening on 260 KHz with my ORION II tonight and heard KSL5 radio in Utah
which broadcasts on 1160 KHz. That would be 900 KHz below their broadcast
frequency. I'm curious about this and wonder what exactly I'm listening
to.
Besides, it is time to talk about something besides headphones... :)
Ron KA7U
I had similar a few weeks ago, and it is possibly "your station" and a
second broadcast station near by proudcing a ifference frequency between the
2
stations and the rig is picking up the combined signal and detecting it at
.260
it is not a harmonic, but could be a difference freq if two strong am
stations are close by.
tom N6AJR
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