I suspect I know what you're thinking of :)...
probably the same thing I was thinking of when
I read the Order: A digitized voice mode where
the transmit channel data rate is sufficient for
transmitting at least twice what is required for
the compressed voice; packetizing the voice into
something
David Little wrote:
Howard,
I am a member of Army MARS in the state of Georgia.
Actually, I should say Region 4 MARS, as we are now under the Region
concept and are merging into a Tri-Service organization.
So far, AF MARS has completely revamped their call-sign structure to
adhere
Kent VE4KEH wrote:
Our ARES group is having difficulty specifying an operating frequency for a
PSK31 net. Is there any website which explains the relationship between the
actual signal frequency, the transceiver frequency, the audio (waterfall)
frequency, USB and LSB for digital operation?
Andrew O'Brien wrote:
FYI...
The Grouply message says:
QUOTE
As far as security
goes, we carefully protect your Yahoo password - we do not phish or do
identity theft. We use it only for discovering your group list and
retrieving messages - we will NOT use it for anything else, like your
Yahoo
Why would one use a 3 kHz bandwidth for a 100 Hz wide mode? Wouldn't
it be more realistic to do comparisons based on a noise bandwidth that
is the same as or just slightly wider than the signal bandwidth?
- ps
Tony wrote:
Mark,
If the SNR is negative, how is it that you can copy any signal?
I've got to agree with Jose here. AX.25 works pretty well on VHF, but
falls apart on HF. But AX.25 is a link-layer protocol, not the whole
suite of stuff that got crammed into a TNC. AX.25 may have been derived
from the X.25 landline protocol, but using the obsolete landline modem
under it is
I hadn't thought of trying a high-speed VHF/UHF modem :) Maybe
that's because I live away from what most people call civilization
and there aren't many VHF/UHF signals around here.
I'd figured on using a CPU personality for overall control, and
doing the work in hardware.
Is the Spartan-3E
John B. Stephensen wrote:
FPGAs are useful for signal processing as you can do many operations in
parallel. FIR filter, FFT and CORDIC modules are available in the free
development software from Xilinx. They are very good for processing
wideband signals or digitizing an entire amateur band
I've been thinking about getting an FPGA board
to play with and see what it will do as far as
hosting an HF modem, or at least the A/D and DSP
portions of one. The board I'm considering has
a Xilinx Spartan 3E FPGA and all of the peripheral
hardware (A/D, D/A, VGA, ethernet, serial, etc.)
one
Andrew O'Brien wrote:
My reading of the message is that Morse code is authorized NOT
mandated. It seems a reasonable decision for a organization often
dependent on volunteers, if they want to use it.. let'em. MARS will
continue to use MT63, ALE, PSK, and many other digital modes.
Andy
Might want to check that one -- I think you'll find it's
derived from BSD, not Linux.
73,
- ps
Ken Meinken wrote:
Actually, the Mac OS is based on Linux.
Is your audio level high enough going into the sound card,
or possibly the gain on the mic or aux input needs bumped
up a bit? I was playing around a bit earlier watching some
signals, and if I got the audio level too low, the displays
didn't show anything but I was still decoding.
73
Paul /
A friend of mine has installed Ubuntu 7.1 and is looking
for gmfsk. Is it available for Ubuntu? (Sorry, I'm a
Fedora user and not all that familiar with the places
Ubuntu packages are kept!)
73,
Paul / K9PS
Darrel Smith wrote:
Is there any particular reason he is looking for gmfsk? I used that app
for a while but now used fldigi. Gmfsk should be available in the
repository, I know it is for kubuntu.
Darrel, VE7CUS
Yes - fldigi doesn't (at least, not yet) support MT-63. I found
the ubuntu
Yep - the best way to handle an emergency is to train for it
using the modes and methods you plan on using for the real thing.
While it might be argued that in an emergency, mixed-mode would
be legal, it wouldn't be for drills.
- ps
Rick wrote:
Maybe theoretically, but if you don't do this on
pcooke2002 wrote:
$3K for an HT!!!
BREATH, BREATH.. SWALLOW
You mean to say that $3k of my tax dollars are being spent on a HT
that you could have spent $200 on.
I have to complain to my city council about my police dept going
digital.
I'd more likely congratulate them on having
Clarification...
Except MT63 was reference to fldigi.
Paul L Schmidt, K9PS wrote:
Except MT63...
Darrel Smith wrote:
I agree with Per that Fldigi does every mode you would want for digital
modes although I use cocoamodem on my Mac for day to day use as it has a
few features fldigi does
AFSK over FM on 29.xx MHz isn't legal here anyway.
Paul L Schmidt, K9PS wrote:
I haven't tried AFSK over FM on 10 meters, but given what I've heard
on 10M FM during the last sunspot maximum, I would definitely agree
with you that the propagation characteristics -- which are obnoxious
enough
I wasn't so concerned about whether it's ISB, DSB, or whatever; I was more
interested in the comment that it would make the rig easy to build. If a
simple rig were built with two balanced modulators from a quadrature RF source
(easy to do), using stereo audio with a sound card program designed
Danny Douglas wrote:
Why is that? FM is the carrier, afsk is the mode. Just as SSB is the
carrier for an AFSK signal. If you can run AFSK on SSB in the other bands,
why not 10? Does it specifically say NBFM only for voice?
That would be an F2D emission. Legal on frequencies where
Don't know... I'll have to do a google search on softrock
and see what it is. If that *is* what a softrock is, I
may just have to get one to play with :)
Jose A. Amador wrote:
Isn't that a Softrock using SDR-1000 or M0KGK software?
Jose, CO2JA
kd4e wrote:
Anyone familiar with NBFM Packet activity on 10M,
29,100 - 29,300MHz ?
I came upon an old Sonar VFX 680 NBFM/CW exciter
that covers 160-2M and it got me wondering why
NBFM is not included across the Ham HF spectrum
bandplan. I don't believe it is any wider than
an AM signal.
KV9U wrote:
Good points, Paul,
One thing that I found with longer distance FM signals on HF, even
though 10 meters can be close to the MUF when it is open, is that there
is a lot of frequency inversion or other anomalies from the ionosphere
that make it rather annoying and
For a simple transmitter, how about a sound card mode that uses the
sound card in STEREO mode with I and Q components on L and R channels,
feeding two balanced modulators, and build a phasing-type exciter
to do J2D type emissions?
Maybe not quite as simple as AM, DSB, or NBFM, but probably pretty
The info the ARRL got was correct - it's in there today.
http://edocket.access.gpo.gov/2007/pdf/E7-729.pdf
Nope - General and higher will have all modes.
For no-code techs, it's the opposite -- except on 10 meters, HF
privileges for codeless techs will be *CW ONLY*: no SSB, no SSTV,
no RTTY, no soundcard digital -- except for CW. ON/OFF keying
using the international morse code.
On 10 meters,
They'll just be on CW and 10-meter SSB. If they were going to put
them on 75m SSB, they might be able to get a 10-36 if they could
get through all the 20-wpm Extra Class Lids that think they own
the frequency they sit on.
- ps
Chuck Mayfield wrote:
Yahoo, Good Buddy. Can I get a 10-36?
Leigh L. Klotz, Jr. wrote:
But why stop there, as you say? I'm reasonably sure someone's already
done this (from the scores I see in the contest logs) but it should be
possible to totally automate the RTTY contests. With wide-band SDR
receivers (and transmitters for that matter) it ought
I haven't yet figured out what the supposed incompatibility between versions
is all about. For most packages I've run, it's either compile straight from
source and install, or do a search and find pre-built binaries that'll run
on my system (Fedora 3). The only thing I've had problems with so
:
Paul L Schmidt, K9PS wrote:
Yep. I was thinking of the 80 meter one. At 130 feet or so per side,
it's pretty big, but still fits in some lots where there's not enough
length to do a 160 dipole. I really should restrict things that require
thinking to before 5:00 PM when I switch the brain
I haven't done much with the 30m allocation -- Rein, PA0R, had some
info on it in his posting. In THEORY, it might be good for NVIS
during the peak of the sunspot cycle, but this time of the sunspot
cycle, NVIS wouldn't be good there. There may be other propagation
modes that may provide some
I've spent most of my ham career on or near 80 meters. The question
depends on what part of the sunspot cycle you're in.
If sunspots are at max, 40 meters is generally solid during the daytime
hours for those distances. At nighttime, 40 meters gets long and you
will need to shift to 80/75
Follow-up -- forgot 160m antennas. While a full-sized dipole or inverted
vee is nice for NVIS, there are options for smaller lots.
A full-size dipole is in the ballpark of 250 feet total length, but a
full-size full-wave loop is only 60 feet or so on a side. Feed it
either in the middle of one
KV9U wrote:
Paul,
A full sized 160 loop is not easy to set up since it needs to be around
500+ feet in circumference (1005 / 1.9 = 528 feet). This would make a
square about 130 feet on a side.
Yep. I was thinking of the 80 meter one. At 130 feet or so per side,
it's pretty big, but
John B. Stephensen wrote:
and 8 kHz maximum bandwidth limit. However, ARRL memebers want more
stringent regulations.
Not all of them.
73,
Paul / K9PS
(Life Member of both ARRL and QCWA who doesn't.)
expeditionradio wrote:
As of 15 December, 3580kHz+ is an obsolete frequency for mainstream
PSK31 in USA. The FCC simply changed the subbands... pulled the rug
out from under us. Now we have to use some of our famous ham ingenuity
to make lemonade out of the barrel of lemons the FCC gave us.
And using the GMRS channels or using a radio that
allows an external gain antennas (external antennas are
illegal for FRS) requires a license that costs more than
the radios.
Unless one chooses to operate illegally without a
license.
That's what happened to 11 meters in the end...
- ps / K9PS /
Roger that. I just assumed with the antenna
gains specified you were on UHF. :) I should've
figured there was a disconnect between the
cost of the set-up being under $30 and those
kinds of antenna gains (particularly on VHF!)
73,
- ps
bruce mallon wrote:
That was not clear I was on MURS
expeditionradio wrote:
Hi Bill,
The FCC did the all the pushing down. They compressed the 80m Data
subband to 100kHz. The only DATA subband on 80 meters for USA after 15
December is 3500-3600kHz. The CW band remains 3500-4000kHz... there
is plenty of space for CW... a total of 500kHz.
Leigh L Klotz, Jr. wrote:
This is an interesting point of view, to take it from an economic and
performance tradeoff. If I might ask (if this threa continues), would
you all mind posting your rig and antenna systems as well? It would be
interesting to see if there is a correlation between
Mark Miller wrote:
What my question
boils down to is generally, what is the accepted maximum bandwidth of
any signal in the Amateur HF bands, given the finite spectrum and
many interests?
There's the billion [insert local currency here] question. Or
actually two questions: what's the
Harv Nelson wrote:
some things you must be prepared to deal with if the help desk at
you ISP knows you are running Linux, they will treat you like a leper.
We recently went through that with our church's system -- we have a
Linux system on the DSL line, running as a firewall (router, proxy
Somehow I doubt the non-extra-class CW ops will go for a
15 kHz segment (3525-3540)
Since 25% of the non-phone band is extra-only, wouldn't it
make sense to designate some of the extra-only sub-band
as digital? Not all extra-class operators operate CW.
expeditionradio wrote:
Proposed New 80
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