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De: Psk31 Digest <owner-psk31@aintel.bi.ehu.es>
Para: <psk31-digest@aintel.bi.ehu.es>
Asunto: Psk31 Digest V1 #110
Fecha: martes 13 de julio de 1999 21:32
Psk31 Digest Tuesday, July 13 1999 Volume 01 : Number 110
In this issue:
Re: [psk31] Taking another look at Pactor
Re: [psk31] Dynamic Range of the Full Color Waterfall (MixW32)
[psk31] 30M QSO
[psk31] More Test Results on Comparisons between MixW32 and PSK31SBW
Re: [psk31] emission type
[psk31] Kachina connections..
[psk31] Re: [dx-list] LOGGER VERSION 6.07
Re: [psk31] Re: [dx-list] LOGGER VERSION 6.07
Re: [psk31] 30M QSO
Re: [psk31] Dynamic Range of the Full Color Waterfall (MixW32)
[psk31] *** PSK31 CD-ROM EFFORT ***
Re: [psk31] Kachina connections..
Re: [psk31] Re: [dx-list] LOGGER VERSION 6.07
RE: [psk31] emission type
[psk31] Secret Project
[psk31] dB Scale in WSCAnalyze
Re: [psk31] 7MHz PSK31 frequency
See the end of the digest for information about psk31-digest
----------------------------------------------------------------------
Date: Mon, 12 Jul 1999 19:15:58 -0700 (PDT)
From: Daryl <wb4yex@yahoo.com>
Subject: Re: [psk31] Taking another look at Pactor
Same here. The last 2 meter packet BBS closed down
after the last computer crash. Reason : Noone much
used it anymore. everyone is using email for messages.
- --- Loren E Page <w7bwi@juno.com> wrote:
> Dear Gerry,
> Not many months ago (not 10 years) I spent some time
> on HF packet and
> found it, as you have, a very poor mode for HF. If a
> person doesn't have
> high power, there isn't much chance of anything but
> slow transfer and
> packet repeats.
>
> Packet was once "pretty hot stuff" here in Phoenix
> on 2 meters, however,
> things have changed with the advent of internet.
>
> ¡Viva PSK31!
>
> 73, Loren W7BWI
===
Daryl CLine WB4YEX <><
Harrisonburg, Va. 22801
<http://www.cfw.com/~jdc>
------------------------------
Date: Mon, 12 Jul 1999 22:14:42 -0400
From: Charles Greene <cgreene@loa.com>
Subject: Re: [psk31] Dynamic Range of the Full Color Waterfall (MixW32)
At 06:31 AM 7/12/99 +0000, Peter Martinez wrote:
It seems to me that Bob's test, while interesting, is not testing the
right things. The waterfall is never going to be black (or blue). If
there are
no signals, the receiver AGC will increase the gain of the receiver,
and the waterfall will be gray (or yellow, in the case of MixW32).
What should be tested is the ability of the operator to distinguish
a weak signal in a gray or yellow background. I ran some non-qualitative
comparisons between the waterfall display in Spectrogram and MixW32
for weak signals Both are in color, and both can be set to have the same
resolution. During the time I was testing, I observed several weak signals
in the waterfall display in MixW32 and none in Spectrogram. However, I
need to make two points: Spectrogram was never designed to display weak
signals, and the ability of Spectrogram to display weak signals depends to
a large degree on the parameters you set into Spectrogram. Of course
you can't change the parameters in MixW32, or even know what they are.
In my opinion, the resolution and the size of waterfall display have more
effect on the operator's ability to detect weak signals than the color, all
other factors being equal.
____________
Try PSK31.
Chas, W1CG
Rhode Island TCPIP Address Coordinator
w1cg@arrl.net
_____________
------------------------------
Date: Mon, 12 Jul 1999 21:41:48 -0500
From: Glenn Wiebe <gswiebe@mb.sympatico.ca>
Subject: [psk31] 30M QSO
Dick - W7DHS wrote:
> Now my life's ambition is to make a psk31 contact on 30 meters when I
> find THE frequency. I'm only 66. I might make it!!!
Dick, I'm 65 I intend to accomplish this noble feat. Call me on
10140.150
(rf) at 03:00 daily (or whatever day you can make it) until we get
together.
Glenn VE4GN
------------------------------
Date: Mon, 12 Jul 1999 23:38:07 -0400
From: "Robert Lay" <w9dmk@crosslink.net>
Subject: [psk31] More Test Results on Comparisons between MixW32 and PSK31SBW
Dear Fellow Warblers,
These test results are a "follow-up" on the tests that were made and reported on
in my message of 7/10/99 7:14PM, titled "Dynamic Range of the Full Color
Waterfall (MixW32)"
The following caveats, definitions and test environment parameters apply to the
tests
reported herein:
1) As usual, some of the test results are subjective. Pictures would help,
but we do not attach pictures to messages addressed to the Reflector.
2) I record relative audio levels in dB with the program WSCAnalyze, version
1.10, by Moe Wheatley, AE4JY, of Duluth, GA. The recorded values are from the
level of the 1000 Hz PSK31 twin peak signal as is being seen in the sound card
by that program. From the documentation provided, we do not know the reference
for dB scale, so all signal levels measured with this program are relative. I do
not know what internal scaling is applied in the sound cards (in the A/D
conversion), or whether they are consistent across all makes and models. My
sound card is Creative Labs Model 4170, a 16 bit PnP card. It does not matter
what my mixer settings or my L/R
balance settings are, so long as they are constant throughout the testing.
Anyone with the same analysis programs and the same sound card can repeat my
measurements.
3) The versions of the software are version 1.03/D of MixW32 and version 1.07 of
PSK31SBW. Program PSK31SBW is used with "Narrow Filter" checked.
4) The aggregate signal supplied to the sound card input jack consists of both
"signal" and noise, and is defined referred to herein as "Input Signal Level".
It should be noted that his level is generally adustable by adjusting the
receiver output level or by adjusting the sound mixer level settings.
5) The Audio Signal Generator that I used is the program WSCGen, version 1.10,
also by Moe Wheatley. The settings used are 1000 Hz, BPSK
Mode, and 3 kHz Bandwidth-limited noise. A condition of "no noise" is a 60 dB
Signal to Noise Ratio (SNR), since that is the highest S/N ratio provided by
Moe's program. The programs WSCGen and WSCAnalyze are available at
www.mindspring.com/~ae4jy/projects.htm
The following extract from the documentation on WSCGen is relevant:
<<Additive Gaussian noise can be added to each signal. The noise can be BW
filtered through a 200-3200Hz. filter trying to simulate a typical receiver
channel. The SNR ratio of zero dB is when the RMS value of the signal equals
the RMS value of the bandwidth limited noise.>>
Therefore, when I report "SNR" in these tests, it is the value shown directly in
the WSCGen program with the check box for "3 kHz BW Limited" checked.
- ------------------------------------------------------------------------------
Conclusions:
a) Programs MixW32 and PSK31SBW both have an ability for printing over a wide
range of SNR's when the Input Signal Level is sufficient. However, the required
minimum signal level for MixW32 can be several dB higher than that for PSK31SBW.
In other words, MixW32 seems to have several dB of penalty with respect to
locking in and decoding signals when the sound card is receiving a low Input
Signal Level.
b) At low Input Signal Levels MixW32 offers a significant advantage in its
ability to locate and display signals. For Input Signal Levels of 25 to 30 dB
below the Input Signal Levels necessary for visual recognition in PSK31SBW, the
MixW32 program clearly indicates the presence of a PSK31 signal in either the
Thick Blue Line or in the Full Color Waterfall. In other words, MixW32 posses a
significant advantage in "locating" signals - even when Input Signal Levels are
considerably below its threshold for decoding and printing them.
Basis for the my conclusions:
Input Signal Levels at which the signal can be reliably printed:
Prog. SNR= -12 dB SNR= 0 dB SNR= +60 dB
- ----------------------------------------------------------------------------
PSK31SBW -62 dB -72 dB -66 dB
MixW32 -58 dB -58 dB -56 dB
Input Signal Levels at which the dsplay is becomes useful:
Prog. SNR= -12 dB SNR= 0 dB SNR= +60 dB
- ---------------------------------------------------------------------------
PSK31SBW -48 dB -52 dB -50 dB
MixW32 -78 dB -77 dB -78 dB
Data could have been taken at additional SNR values. However, it was found that
at SNR less than -14 dB, performance is extremely poor with either program. The
+60 dB SNR is the maximum SNR that can be set on the signal generator program.
The trend seems to be consistent across the range of SNR values shown.
Again, let me emphasize that "low Input Signal Level" does NOT mean low S/N
ratio. The SNR can be quite high while the Input Signal Level can be quite low
due to mis-adjusted audio levels into the sound card. Remember, there is no AGC
system that automatically keeps the Input Signal Level to the sound card at a
constant level.
Additional Clarification on S/N Ratios: The S/N ratios that are quoted herein
may seem strange - especially when we hear values such as SNR = -12 dB. I have
chosen to use the values provided directly by the Signal Generator Program
(WSCgen) rather than convert them to the bandwidth of the signal processing
algorithms for the following reasons:
1) Even though I have bandwidth data for Peter's software, I do not have the
corresponding parameter for Nick's program. Nick's program does not
provide a choice of filters, as does Peter's program.
2) By using the direct read-outs of SNR from WSCGen, I believe it will be easier
for others to compare their results with mine.
Nonetheless, if we WERE to convert the S/N ratios, which are given here in the 3
kHz bandwidth, into S/N ratios for a processing bandwidth of 31 Hz, for
example, the S/N ratios would be 20 dB larger than given herein (10 log of the
ratio 3000 / 31).
73 de Bob Lay, W9DMK, King George, VA
http://www.qsl.net/w9dmk
http://www.fortunecity.com/meltingpot/albania/784
------------------------------
Date: Mon, 12 Jul 1999 22:45:40 -0500
From: Martin <rutherford.ulea@mcleodusa.net>
Subject: Re: [psk31] emission type
Hi Russ. I asked the same question of the ARRL Technical staff. They
said it is G1B, or G1D depending how it is used.
Russ Pillsbury wrote:
>
> Hello PSK31'ers. I am new to this list and have a question about PSK31.
> What, if any, is the official FCC emission type for PSK31? I've perused all
> of the info I can find from the PSK31 web site and cannot find this
> information. I guess it might be G7D, but I'm not at all sure.
>
> Thanks, 73 - Russ K2TXB
>
- --
Cul8r
Martin Campbell rutherford.ulea@mcleodusa.net KB0HAE
------------------------------
Date: Mon, 12 Jul 1999 23:12:56 -0500
From: Gilbert Gibbs <gilgibbs@centuryinter.net>
Subject: [psk31] Kachina connections..
When I sent out a query about needing help for my Kachina to set up for
PSK, I didn't expect much response, but got three returns overnight!
Thanks to all who gave me more hints & kinks than I'll ever get from our
"famous" ARRL - which seems to be dragging in reverse against the flow
of the river. (I'm a Life Member, could use those bucks now for more PSK
software, but just sour grapes...).
73's good contacts & everyone enjoy "warbling"!
Gil, WA5YKK
------------------------------
Date: Tue, 13 Jul 1999 04:31:01 -0500
From: jglock2 <jglock2@airmail.net>
Subject: [psk31] Re: [dx-list] LOGGER VERSION 6.07
Good morning to ALL:
I have a question about the LOGGER ver 6.07b.
Is this the LATEST version that is available??
Also, in the LOGBOOK area of the LOGGER program, there is nothing
available for PSK31 as a transmission mode???
Can anyone help me here - TNX!
de Joe WA6AXE
------------------------------
Date: Tue, 13 Jul 1999 07:35:02 -0400
From: Vince <wa2rsx@worldnet.att.net>
Subject: Re: [psk31] Re: [dx-list] LOGGER VERSION 6.07
Hello:
As far as I know, vers 6.07B is the most recent available for LOGGER by
K4CY.
As for the mode of operation notations in the Logbook, there is an option to
add New modes. Must read the HELP files.
73s, AND, Have Fun out there, OM !
~Vince~
------------------------------
Date: Tue, 13 Jul 1999 07:59:35 -0400
From: Charles Greene <cgreene@loa.com>
Subject: Re: [psk31] Dynamic Range of the Full Color Waterfall (MixW32)
At 10:14 PM 7/12/99 -0400, Charles Greene wrote:
>It seems to me that Bob's test, while interesting, is not testing the
>right things. The waterfall is never going to be black (or blue). If
>there are
>no signals, the receiver AGC will increase the gain of the receiver,
>and the waterfall will be gray (or yellow, in the case of MixW32).
>What should be tested is the ability of the operator to distinguish
>a weak signal in a gray or yellow background.
I am proposing a test to ascertain the minimum discernable
RF level of a signal in different displays. The setup will use
the receiver and a calibrated signal generator. It will be similar
to the sensitivity measurement of a receiver, except instead
of using a SINAD meter, it will use two different displays.
Basically, the test will measure the low RF level needed to
allow an operator to detect a signal.
Hook up a calibrated signal generator capable of CW
operation and SSB operation to the receiver input.
Use the PSK31 computer connection and start one waterfall
display. With no tone modulation (CW), tune the signal
generator to the frequency displayed by the waterfall display
and set the output to a very low level so that the signal
cannot be observed. Gradually increase the signal level
from the signal generator until a signal is just detectable
in the waterfall display. Record the signal generator
output. Repeat several times and record the levels.
Start the second waterfall display and repeat the experiment.
The difference in signal generator output readings is a
measure of the difference in the minimum detectable signal
level of the display, on that receiver, at that frequency.
It is only useful as a comparison of which display will detect
weak signals better.
You can repeat the test to investigate other factors
such as the effectiveness of receiver filters on the
detection process, the use of a two tone SSB signal
and an actual PSK31 signal, and the ability of a
display to detect a signal in the presence of a strong
adjacent signal (QRM).
I have a suitable signal generator, a service monitor.
If I have time before my vacation next week, I'll
run the test and report the results on this forum.
A similar test performed on an actual received signal
is described in the following article:
"A Needle in an RF Haystack" by Steve Ford, page
51 of August 1999 QST.
The objective of Steve's test was to determine the
transmitted power that a particular display,
the FFTDSP by AP9Y, could detect under
actual transmitting conditions. Steve
was receiving KF6I transmitting
in CA, at his home in CT, on 20 meters.
The transmitted power for the minimum
detectable signal was 10 mW, under the
conditions of the test.
____________
Try PSK31.
Chas, W1CG
Rhode Island TCPIP Address Coordinator
w1cg@arrl.net
_____________
------------------------------
Date: Tue, 13 Jul 1999 08:26:25 -0500
From: "Nathan Odle" <nodle01@mail.coin.missouri.edu>
Subject: [psk31] *** PSK31 CD-ROM EFFORT ***
Hi all,
I'm slated to give a presentation on PSK31 at the local club (Central
Missouri Radio Association) tonight, and in preparation came up with
something I think is pretty neat. What I've done is create a PSK31 CD-ROM.
This CD-ROM contains most of the PSK31 software out there for ALL platforms
(at least what is share/freeware), some of the documentation (namely that
written by G3PLX and also the bandplan), and (here's what I think is cool)
on-air audio. I've created it as a "CD Extra" ROM, which means that if you
put the CD-ROM in your audio CD player, you will be greeted with the
warbling tone of a real live, on-air PSK31 contact, QSB, QRM and all. This
is neat because you can plug your CD player into your Soundcard/DSP input
and copy it on the screen. I've also included the transcript of the
exchange for comparison, as well as MP3 versions of the audio files.
This is an early version of the CD, so I've only got one little contact, but
it's a DX one with that big French station ;) I plan on expanding the CD to
include more documentation on topics like rig interfaces, more audio, and
more software (but the collection's pretty complete as-is).
I've burned 5 CDs in preparation for the meeting tonight, and I expect to
give them all away, but here's what I'll do for the rest of the world:
Expect to see a new PSK31 website sometime in the near future. On this
website, I will have available for download the 'ISO image' which is
essentially a large file that's an exact image of the CD. *Anyone* with a
CD-R should be able to take this image and make an exact duplicate of my
work, including the CD Extra feature. I'm not positive that this will work
with the CD Extra, but I believe that it will.
The next thing I will do is "seed" the community with 10 or 20 PSK31 CDs.
The one condition to this is that the CDs will only go to people with CD-Rs,
and they must be willing to fulfill other requests for the CDs. Their
names, callsigns, and emails will be posted on the new PSK31 website for
interested hams to contact. I'd also like to get some of the CDs overseas,
either through ISO image download or shipment of a few seed CDROMs. This
"distribution tree" has worked well for the QRP-L guys, and I don't see why
it couldn't work well here... I will be paying postage on the initial
distribution, but the second tier will have to decide how they want to
handle their situation. I'm thinking that they might want to pay postage
themselves if provided the CD-R media, otherwise charge a small service fee
for the media and S/H. This will happen sometime after the initial ISO
image posting, so just sit tight for details. Also, by way of keeping
somewhat up-to-date, I plan on updating quarterly with new content.
At the moment, I'm interested in feedback. I believe that this will be a
good way to distribute PSK31 to "the masses", so to speak, especially those
that don't have good access to the Internet. I would also be very
interested if any of you have anything you'd like to *contribute* to the
CDROM, such as interface guides, operation guides, new PSK31 software, etc.
I also would be interested in some audio files generated through one of
these "HF simulators" that I keep hearing about. In addition, if you'd like
to be one of the "2nd tier" distributors PLEASE contact me. We'll need good
people who can keep their committment to make this work.
Feel free to contact me at: nodle01@mail.coin.missouri.edu
Thanks,
Nathan Odle, KB0NNV
Columbia, MO
------------------------------
Date: Tue, 13 Jul 1999 10:30:31 -0300
From: py2pll@unetsul.com.br (Marcus Ramos (0946))
Subject: Re: [psk31] Kachina connections..
Hi ..
>I'm "in the process" of getting a Kachina system (could you really
>define that transceiver as a "radio"?) going, and have a Pentium-S -
>based CPU PC, 133 MHz, equipped with a SoundBlaster AWE64 soundcard, and
>am searching for some solid answers to how to connect the control head
>or access port to the soundcard so I can participate with the rest of
>you in "warbling".
Piece of cake! The auxiliar connector is a DB25. In advance got 2 small
isolation transformers say 600:600 ohm.
Use the balanced line input at Kachina ACC connector and a 2 wire+shield
cable to the xformer. The other side is straight connected to SBlaster line
out. Mine gives -2dB ALC with WAV mixer at 100% and VOL at 40%.
The SB line in, another xformer, wired trhu a 1 conductor shielded cable to
"RX audio Out" at the same DB25 (unbalanced). With Line In at maximum on SB
Mixer (rec section) you'll get the correct levels.
Remember that the radio is already connected to the computer, so their
grounds are at the same potential. The isolation xformer are necessary to
prevent ground loops. On mine I started without xformer, no problems at all
but since I run 3 sound cards and an EVM56000DSP I have four possible
sources so xformer is there to prevent any damage due to constant "patching"
between audio applications.
I keep the MIC level at Kachina at 100%, so to balance with voice use I
trimmed a small pot that exists inside the control head. Note that I did
this by my own risk, it's not a factory recommended procedure.
BTW, since calibrated to PSK31 it's ready for any other software that run
under windows and uses SB Card such as W95SSTV, JVComm32, Mix32, etc etc
73
Marcus, PY3CRX/PY2PLL
http://www.unetsul.com.br/py2pll
- ---
------------------------------
Date: Tue, 13 Jul 1999 09:40:11 -0500
From: "George T. Baker" <w5yr@swbell.net>
Subject: Re: [psk31] Re: [dx-list] LOGGER VERSION 6.07
Bob has Version 6.07c in beta that should be released any day now. It
contains some enhanced PSK31 capabilities.
72/73, George AMA 98452 R/C since 1964
Amateur Radio W5YR, in the 53rd year and it just keeps getting better!
AutoPOWER Systems, Fairview, TX (30 mi NE Dallas) Collin County
QRP-L QRP-ARCI FISTS NORCAL ZOMBIE ARS 10-X 33.2 N 96.6 W EM13RE
------------------------------
Date: Tue, 13 Jul 1999 10:59:12 -0400
From: "Russ Pillsbury" <k2txb@dxcc.com>
Subject: RE: [psk31] emission type
> Hi Russ. I asked the same question of the ARRL Technical staff. They
> said it is G1B, or G1D depending how it is used.
Thanks Martin, do you know what they mean by "how it is used"?
Russ K2TXB
------------------------------
Date: Tue, 13 Jul 1999 11:15:04 -0500
From: "Nathan Odle" <nodle01@mail.coin.missouri.edu>
Subject: [psk31] Secret Project
OK, 2 posts in one day for me... I know that's amazing, but guess what?
This is another announcement...
I'm not going to tell you what the project is, so as to save my sanity in
case it never gets finished, but I'll tell you this: it's about the coolest
PSK31 application yet. The ingredients are Java, C++, Linux, a computer
controllable rig, and many late nights - and it should (like my CD project)
bring PSK31 to even more folks. However, I'm using it as a "learning
project", and believe me there's a lot to learn - so don't get too anxious.
Suffice it to say that when I get the guts of this thing up and running I'm
going to start soliciting criticism. In the meantime here's a couple of
teasers, I mean questions, for you to mull over:
1. Does anyone have a computer controllable rig to loan or donate for a
good cause? A really good cause?
2. Could you guys make do with a simpler, slower, lower resolution
waterfall?
Trust me, this will be something for the ham community to brag about if it
gets off the ground...
73,
Nathan Odle, KB0NNV
Columbia, MO
nodle01@mail.coin.missouri.edu
------------------------------
Date: Tue, 13 Jul 1999 13:08:35 -0400
From: "Robert Lay" <w9dmk@crosslink.net>
Subject: [psk31] dB Scale in WSCAnalyze
Dear Fellow Warblers,
Referring to my message titled "More Test Results on Comparisons between MixW32
and PSK31SBW" of 7/12/99, 11:38 pm. - I believe that I now have an understanding
of the dB scale in program WSCAnalyze, which was used for signal level
measurements in my tests.
We all know that Peter's program turns the Waterfall Displayl Blood Red when the
A/D converter is overdriven. In measuring that level (that causes the Waterfall
Display to go red) with the analyzer program WSCAnalyze, I found that it
corresponds to full scale, or +10 dB on Moe's dB scale. It is also noted at the
bottom of his display that this level is desribed as max value of 32767 and that
the RMS value is around 25000. It dawned on me that the "16 bit" dynamic range
of a sound card would be 0 to 32767 if we are set up for monaural as opposed to
stereo. Therefore, the conclusion that I have reached is that the following are
all the same level:
Blood Red Waterfall Display in PSK31SBW
32767 Max value -------- in WSCAnalyze
+10 dB -------- in WSCAnalyze
I also took an absolute voltage reading of the 1 kHz level that it takes to
reach 0 dB in that same analyzer program while using the Mixer Volume control at
full scale. That level is 167 millivolts. Therefore, the RMS signal voltage at
the sound card input jack (Line-In) that corresponds to the above references is
a
signal level of 10 dB above 0.167 volts, or 0.528 volts - more or less. I say
"more or less" because my Ballantine Model 323-01 True RMS Voltmeter has not
been calibrated and could very well be off by as much as 10 %.
Therefore, I would add one more item to the three quantities in the above list,
and that is a value of 0.528 volts, rms.
For those who would like to translate the Input Signal Levels that I reported in
the abovementioned message into RMS voltages, all you have to do take the level
I reported and convert it with the following formula:
RMS Volts = 0.167 x 10 ^ (Level / 20)
where "^" means "raised to the power of"
For example:
Level = -30 dB
RMS Volts = 0.167 x 10 ^ (-30 / 20) = 0.167 / 31 = 0.0053
= 5.3 millivolts
If your Mixer Volume setting is at any value other than full scale, you must
correct by another factor. The volume control is logarithmic. That means that it
changes in some number of dB per step. On my system, it seems to cover a range
of 45 dB from the lowest Tick mark up to Full Scale. To correct for the
attenuation of that volume control use a factor of (% x 0.45 dB), where "%" is
the volume control setting
expressed as a number from 1 to 100.
In the example above, if my volume control setting is at 50%, then I must
correct by the 22.5 dB of attenuation introduced by the volume control, which
means that I actually input a voltage level of 70 millivolts to obtain the
WSCAnalyze reading of -30 dB.
73 de Bob Lay, W9DMK, King George, VA
http://www.qsl.net/w9dmk
http://www.fortunecity.com/meltingpot/albania/784
------------------------------
Date: Mon, 12 Jul 1999 20:59:37 +0000
From: Peter Martinez <Peter.Martinez@btinternet.com>
Subject: Re: [psk31] 7MHz PSK31 frequency
From Peter Martinez G3PLX
Replying to Richard Mock on the 7 MHz question. the upper limit of CW
in the IARU region 1 plan is 7035.0, so we have no problems here. In
fact any PSK31 user that does stray below 7035.00 gets very quickly
jammed out by CW fans exercising their elbugs, especially at
weekends. This happened with AMTOR 20 years ago when activity became
established BELOW the bottom of the IARU digital band. This is why
you have heard me several times urging PSK31 users to stay within the
bandplans: If PSK31 activity developes outside the digital bands and
then becomes very popular, this will trigger a jamming war which we
will inevitably lose, as we did on AMTOR on 7 MHz 20 years ago!
PS, we can't have a shorter code for backspace: all the shorter ones
are already allocated, and there's no way I am going to propose
changing the code now. You will just have to learn to type better!
73
Peter
------------------------------
End of Psk31 Digest V1 #110
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