Sorry for the bandwidth, but I am trying to find G3RZPs email address-I have
checked the
usual sources! Can anyone help?
Tim VE6SH
>From force12e@lightlink.com (Natan Huffman) Wed Nov 13 17:46:24 1996
From: force12e@lightlink.com (Natan Huffman) (Natan Huffman)
Subject: 15 meter propagation
Message-ID: <199611131747.MAA18255@light.lightlink.com>
This morning whilst tuning around 15 meters at 1530z, I came across several
stations calling CQ. This in itself is a positive indication that
propagation is not so bad, but what made it even more interesting is that
several of the CQ'rs were from VK. Answered one of the VK3 as had a nice
long chat. Seems that this was the first time he worked the East Coast as
it was 3:00 AM local time for him. We marveled at the path for a while and
I finally moved on to answering other VKs calling CQ.
I think this experience is noticeable in that an opening to VK at that time
of the AM is extraordinary. The path was definitely long path and per
GeoClock, this path had a substantial part of it in darkness. The signal
peaked at the right place for long path and was uncopyable using any other
beam heading except for direct long path.
I wonder what propagation mode was involved here? If you could count on
working VK/ZL through Europe during the CQWW, that would change my strategy
somewhat. Unfortunately, I don't ever remember being answered by a VK
during a 15 meter run into Europe. Of course long path openings of this
nature into VK are commonplace on 20, 40 and 80, but I don't think 15 meter
propagation into this part of the world via longpath is so common.
Natan
W6XR/2
W6XR@AMSAT.ORG
>From kr2j@ix.netcom.com (Robert E. Naumann) Wed Nov 13 18:46:11 1996
From: kr2j@ix.netcom.com (Robert E. Naumann) (Robert E. Naumann)
Subject: 15 meter propagation
Message-ID: <01BBD169.FF2F93E0@dfw-tx14-10.ix.netcom.com>
During sunspot peaks, this is actually quite common. I have been a 15
meter aficionado for a long time and you can work almost anything any time
of day or night if the conditions are right. I have worked VK, ZL, VU, YB,
JA, KH0, etc etc in the morning on 15m. On a real good day, you can work
Asia over the south pole just before sunrise. For us at K2GL, this was the
most likely time to work VS6. Really cool stuff .
ILTHRS (who remembers that ?)
N5NJ
>From kr2j@ix.netcom.com (Robert E. Naumann) Wed Nov 13 19:36:00 1996
From: kr2j@ix.netcom.com (Robert E. Naumann) (Robert E. Naumann)
Subject: Summary: where exactly is the band edge?
Message-ID: <01BBD16A.1E2FAC80@dfw-tx14-10.ix.netcom.com>
Hi Kris!
If you read the next paragraphs, I addressed your concerns:
"If the above principles and theory are correct, and you have technically
acceptable opposite sideband suppression that meets the guidelines set out
in Part 97,..."
Seeya!
N5NJ
----------
From: Kris Mraz, N5KM[SMTP:mraz@rockdal.aud.alcatel.com]
Sent: Wednesday, November 13, 1996 7:24 AM
To: Robert E. Naumann
Cc: cq-contest@TGV.COM
Subject: Re: Summary: where exactly is the band edge?
> Theory:
> Theoretically is no energy between your center frequency and say 200 or 300
> hz or so ? All energy is between whatever the lower start "point" of your
> bandwidth is at 200 or 300 hz and goes up to 3khz or more (if you have a
> bad signal) from center.
>
> Agreed ?
Bob,
I agree, in theory, but when considering real world transmitters one
would have
to worry about your opposite sideband being suppressed >40db (ref.
97.307).
--
73
Kris N5KM
mraz@aud.alcatel.com
>From kr2j@ix.netcom.com (Robert E. Naumann) Wed Nov 13 19:36:14 1996
From: kr2j@ix.netcom.com (Robert E. Naumann) (Robert E. Naumann)
Subject: Summary: where exactly is the band edge?
Message-ID: <01BBD16A.20F84260@dfw-tx14-10.ix.netcom.com>
Tom,
I think you missed my point - or - we're not talking about the same thing.
I'm talking about the stuff that if, as in my example, if you were
transmitting right on 21.200.000 USB, you would have no signal BELOW
21.200.000. The stuff I believe you're talking about extends further ABOVE
your operating frequency on USB. The opposite would be true on LSB.
Agreed, that your signal may go further than the 3khz and I agree that
operating on 3753 on LSB does not necessarily mean that all of your signal
is completely above 3750.
For the QRM part, I think you're missing the fact that the receiver
"listens" to a (typical) 3 khz piece of the band extending upward from your
dial frequency on USB and downward on LSB. What this means is that your 3
khz bandpass moves as you turn your dial. In my example again, you would
be listening to me on 21.200.00. You turn you dial to 21.199. You still
hear me. Does this mean that I'm out of the band - heck no! What it means
is that your receiver is still 2khz inside the band! This is why I say to
just flip to LSB on a USB signal to see if he's really out of the band.
Unless his opposite sideband suppression is whacked out, you should hear
nothing. If, under these circumstances, you do hear the stations' signal,
by all means let him know that something may be wrong.
73,
Bob Naumann
N5NJ
----------
From: W8JITom@aol.com[SMTP:W8JITom@aol.com]
Sent: Wednesday, November 13, 1996 8:27 AM
To: kr2j@ix.netcom.com
Cc: cq-contest@tgv.com
Subject: Re: Summary: where exactly is the band edge?
Hi Bob,
In a message dated 96-11-13 07:22:58 EST, you write:
>Principles 1 and 2:
>1- When you're on USB, your signal is above the indicated frequency.
>2- On LSB, your signal is below the indicated frequency.
>Theory:
>Theoretically is no energy between your center frequency and say 200 or
300
>hz or so ? All energy is between whatever the lower start "point" of your
>bandwidth is at 200 or 300 hz and goes up to 3khz or more (if you have a
>bad signal) from center.
>
>Agreed ?
No.
My ICOM 751A (using the Mil Spec or commercial standards, not the ARRL's)
measures -25 dB for third and -28 for 5th order products. In addition it
has
higher order products extending out for many kilohertz.
(I re-worked it and it is much better, now in the -35 dB range)
If my MODIFIED and IMPROVED rig is set within ten KHz of the band edge,
its'
output would contain emissions outside the band. If S meter's were made and
calibrated correctly (they are not) and I was 40 dB over nine, my crud
would
be about S-9 outside the band if I was parked on the edge.
If IMD isn't bad enough, turn to the page in the manual where the
manufacturer gives filter specs. Look at its' SSB filter attenuation.
This was always a problem on 160 and on other bands where weak signals and
strong SSB signals are mixed. Some operators look at their dials and think
(quite incorrectly) their signals extend in one direction 3 KHz, but in
real
life they most certainly do not.
And this is all true both in theory and in practice. Operating on the edge
of
a band or a few KHz from a weak signal area is Liddish.
73 Tom
>From WWalsh@imtech.com (Walsh, Warren) Wed Nov 13 22:58:00 1996
From: WWalsh@imtech.com (Walsh, Warren) (Walsh, Warren)
Subject: 15 meter propagation
Message-ID: <328A52CE@imtech-smtp.imtech.com>
----------
From: owner-cq-contest
Sent: Wednesday, November 13, 1996 12:46 PM
To: force12e
Cc: cq-contest
Subject: RE: 15 meter propagation
During sunspot peaks, this is actually quite common. I have been a 15
meter aficionado for a long time and you can work almost anything any
time
of day or night if the conditions are right. I have worked VK, ZL, VU,
YB,
JA, KH0, etc etc in the morning on 15m. On a real good day, you can work
Asia over the south pole just before sunrise. For us at K2GL, this was
the
most likely time to work VS6. Really cool stuff .
ILTHRS (who remembers that ?)
N5NJ
I Love This Ham Radio S..T!
K2BM
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