Monday, June 22, 2009

eXTREME

Now here is some news. I think this will go a long way to pump up interest in SDR

At Dayton this year K1DG asked to speak at the SDR forum. His topic an extreme contest category with SDR at the center. It seems he and K3LR had taken a shine to the possibilities of SDR in the contest world. I have been beating that drum for several years. The advantages are obvious You can have a receiver explore vitrually every station on the bands at least on CW and digiatla modes. You can have the program determine the multiplier propagation QSO rate/pileup of these stations and you could have the program make a guess as to the workability of any station at any given time using something called monte carlo analysis and make a list for you.

You could have a remote receiver or a bank of remote receivers listen to your run TX freq and help you cut down on broken calls thereby improving your efficiency You could use the remote receivers in a diversity sense and you could us remote transmitter sites as well given the vagaries of propagation. If the DX is hearing W6 and you are K4 then simply turn on the W6 transmitters

You could redesign the interface. In stead of a radio you may decide a game conroller is a more efficient interface and you may come up with some kind of cockpit display instead of a "radio" and fly your way throgh the contest a million possibilities present themselves

Here is the announcement

"This year at Dayton, the new CQWW Xtreme categories were announced.

These new categories (single-operator and multi-operator) have been
established to allow amateurs to participate in the CQ WW Contest
while experimenting creatively with Internet-linked stations and other
new technologies that currently are not permitted in any of the
existing contest categories. The full rules for the new Xtreme
Category, as approved by the CQ WW Contest Committee, appear in June
CQ magazine and also at:

http://cqww.com/CQ_WW_Xtreme_Rules.pdf

This PDF file may be copied and re-posted to other Web sites as long
as this text is included: "Reprinted with permission from the June
2009 issue of CQ magazine; copyright CQ Communications, Inc."

Please forward this email to your local club reflectors and newsletters.

The new categories are effective with the 2009 CQ WW Contest later this year.

In essence, (almost) anything goes! The "almost" part means that you
must obey the rules of your country, including power (up to the CQWW
1500W maximum), licensing, and remote operation (if you use it).

It is permitted to use multiple transmitting sites with one callsign
(if legal in your country), but all transmitting sites must be located
in the same country and CQ zone, and only one signal is permitted on a
band at any time. Single-ops with packet, Skimmer, robot stations,
on-line databases, etc. are OK! Multiops with remote operators and
remote receiving sites around the world...OK!

The initial response at both the Contesting Forum and SDR Forum at
Dayton was very positive, with some of the SDR Forum attendees
actually challenging each other in public! This is a chance for
experimenters to see which technology innovations actually work best
in competitive situations.

If you have questions about the rules, please send them to Xtreme@cqww.com

There is an also email reflector (Xtreme-talk@contesting.com) set up
for discussions relating to these new categories. You can subscribe by
sending email to Xtreme-talk-request@contesting.com with the word
SUBSCRIBE in the subject line and message text, or go here:
http://dayton.contesting.com/mailman/listinfo/xtreme-talk
(thanks, K5TR)

K3LR has stepped up and is sponsoring the K3TUP Memorial Trophies for
the winners of the single-op and multi-op Xtreme categories.

73, and let the Xtreme Contesting Games begin!

Doug K1DG"

I am amazed and gratified that such contest luminaries as K1DG and K3LR have begun to embrace the reality of software.

I predicted this would come years ago. This is the dawning of the ascendancy of software

See also N4HY's blog

73

Friday, June 19, 2009

CW like butter


This is what I have been contending with as far as activity. This is a shot of the 40M centered around 7016. Virtually NO signals. Of course when there are no signals you start to think of other things to do.

Recently in the development channel of PowerSDR there has been a lot of work on CW performance. I decided to give the radio a performance check since I had the latest version of the "test" branch open on the F5K. I set the delay to minimum and I had the panadapter set to 96k since I had recently been playing with the wide band image rejection and that is the correct bandwidth for running the automatic calibration and initialization for that mode. For the algorithm to set up correctly it needs an initial value to set up off of. I usually run at 48K bandwidth because you get filters that are a tiny bit sharper. That is the advantage of 48K With the higher bandwidths on the other hand you get significant reduction in "lag". This "lag" problem is nothing like the "lag" of yester year in the SDR-1000 days. The processes in the radio have attained enough efficiency that lag at any bandwidth has not been a consideration for a long time in my opinion.

In CW there has always been a switching artifact at very high speed. When you go from TX to RX in a QSK setting there would be occasional annoying pops. Today at 96K at minimum delay (10ms) running 60 wpm there were virtually NO pops. The QSK was as butter smooth as any Ten Tec I ever owned. I have had Ten Tec's for years. The most responsive CW rig was the 580D. It had the famous TT audio derived AGC and I swear that radio could go 120wpm and not bat an eye. This morning the smoothness of my F5K rivaled my memory of my trusty old 580D. I used a AL-1500 with that radio and the QSK switching board. Since that time I sold the AL-1500 and bought a Acom 2000A. The Acom is all facny but it is not as good a CW amp as the old AL 1500 with the QSK board. Since that time I have switched my CW habits to semi break in so things don't sound like machine guns when I transmit. The new level of CW smoothness I believe to rival my old set up.

I do have an external electronic QSK switch in the line with my AL-80B amp and given how well this works I'm going to give that a go tonight and see how it plays

Like the logo says "things just keep getting better and better"

73

Thursday, June 18, 2009

The bands this morning

I tuned the bands prior to leaving for work. Nothing exotic but 40 had a LOT of JA's this morning many calling CQ. 80M had one lonely JA way down in the mud. I would have totally missed him except for skimmer. I could see the faintest of coherence in the static on the waterfall

160 was completely dead

Its June 18th and I find it amazing there were so many JA's on this morning. Good signals some as loud as s-7

Maybe its a good thing ol Sol is still snoring

73

Tuesday, June 16, 2009

Survey

A survey over on Eham regarding SDR

http://www.eham.net/survey/

Very interesting response. Even a few years ago most people would have considered SDR as some aspect of a computer connected to a conventional radio. But this survey shows nearly half of the respondents have actual physical contact with true SDR.

If you have a second give your opinion. I think this is good way to measure changing attitudes.

73

Thursday, June 11, 2009

Summer Time Bands


Usually I hardly even turn on the radio in the summer. The static is just too much to handle. I live on the east coast of Florida and if there isn't a thunder storm over head there is one within 100 miles of the shore. Since I've gotten the new Flex radios however I find myself turning on the radio even now in the dog days.

This morning I was on 40M listening to a ZL1. He was working mostly US and Canada. He was perfectly Q5 and about s-4 to s-6. I can't remember a time when signals out of the pacific were this copyable this last in the season. I don't know whether to ascribe the conditions to the state of the sun, but my inclination is to ascribe it to the Flex system. The way the AGC works I think is the key. With my legacy radios the AGC was always engaged due to the static. With all my other radios the static owned the AGC even if I was running ultra super short delay. Because it was hardware involved and it affected multi stages you could never get the attack to not attack, so you were never operating at a DX quality gian setting. With the Flex on the other hand you always operate at best gain. In fact with the flex I don't use the short decay at all. I set it for the long decay and set the ambient band noise to "tollerable". With those settings I hear DX that in years past would have been simply "I know someone is under there somewhere but I can't tell who"! With the radio set to "tolerable" I can sit and listen for hours without the fatigue of the static. This means it has extended my radio enjoyment by months. This turns out to be no joke. I was listening to some of my 75M buddies the other night and all they could do was complain about how bad the static was. At my QTH the static was not bad at all. You could write that off to my locatoin except at least for some of the guys I am at most 150 miles.

This morning I was using the F3K and my 45ft 3 radial vertical. I'm still playing around with that antenna. Its remarkable how well it works. I'm sure I will become bored with it soon enough but in the mean time TMF!! (too much fun)

73

Sunday, June 7, 2009

More 6M

I've been busy with family and this and that. On the flex reflector I read this post by W9DR regarding his experience comparing a F3K with the F5K. The results are interesting to say the least. I'm not much of a 6M op, but his conclusion is also my impression

Thanks to Stew, W4MO, I compared his SDR-3000 to my
SDR-5000A on 6 meters. Here
are the results.

I did an "A-B" test using an antenna of stacked 7
element 31 foot M2's with 1/2 wave spacing and
phased by a W8IF HB Q-Bar. The test was mainly to
find out how the receiver of each would perform on
weak signal 6 meters work. The band was NOT open.
The SDR-3000 would put out 100 watts as well the
SDR-5000A on transmit. I ran the same software
(Pretty Betty) on each radio.

The SDR-3000 had the same sensitivity as the
SDR-5000A......BUT...... the SDR-5000 HAD a 6 meter
preamp in the loop! The SDR-3000 needs NO preamp.
I did try the AR2 preamp on the SDR-3000 but it did
NOT improve the signal to noise! The SDR-5000A
HAS to have a 6 meter preamp for weak signal work!

So, the SDR-3000 is a GREAT 6 meter rig RIGHT OUT
OF THE BOX! The K3 Elecraft needs a preamp, or
Elecraft would not build a stand alone 6 meter preamp
for it. ($149.95)

I did use the SDR-3000 during a 6 meter band opening
....(100 db signals) and it performed as well as
the SDR-5000.

All I can say is, thank you FlexRadio for building
a rig that works great on 160- 6 meters. When the
word gets out that the SDR-3000 works great on 6
meters, the 6 meter weak signal guys will want one.
You can't go wrong for $1600 with all the features
of the panadapter, noise blankers and constant
improvements!

Dave, W9DR

73

Tuesday, June 2, 2009

Meteors


Lyrid Meteor and Milky Way

I just received a note from Dave W9DR. I've met Dave a time or two at the Flex Booth at the Orlando Hamcation. He always fly's his colors wearing a Flex T shirt.

Here are some excerpts from his emails to me

Hi Lee, I really enjoy your SDR blog. I have an SDR-5000 and run meter scatter every morning on 6 meters when the band is NOT open. I use a FlexRadio SDR-5000, 7 element 31 foot yagi over another 7 element at 1/2 wave spacing. Using a W8IF HB Q-bar for phasing and 1/2" super flex coax from the watt meter in the shack to the driven elements on the yagis. HB 8877 Amp.

He said he would send a writeup and a couple of screen shots





The above shows two screen shots on a FlexRadio SDR-5000 panadapter on the 6 meter band.

The first is a screen shot showing the panadapter in "Peak" hold for about 30 seconds. In this mode, the signals shown are over a 92 KC band width on the 6 Meter beacon band. The signals are propagated to my QTH in SW Florida (EL86) by meteors (the band is not "open"). These meteors are not coming from a meteor shower, but rather random meteors that occur daily and are best seen right after sunrise. This takes place 365 days a year. My antennas are pointing north and the 'Peak" will show the highest signal above the noise, and is recording at 15 frames per second for the period I select (usually about 30 seconds). The beacon signal, as displayed by the panadapter, will be the highest (vertical peak) achieve during this period.

The second screen shot is a zoomed-in view of the panadapter, showing higher resolution view of the meteor scatter signals, and can even show doppler (signal frequency shift) or chirpy beacon signals. Most beacons seen are running 50 to 100 watts. Generally, beacons running 10 watts or under cannot be seen above the noise floor. Note the signal strength in 3 db steps, showing signal strength above the noise floor.

At the Dayton Hamvention 2009, a group of us 6 meter "nuts" set up a receiver in the flea market with an SDR-5000 and two stacked 4 element beams. We could see my beacon in SW Florida (915 miles) on the panadapter via random meteors in the flea market at Dayton, Ohio. The band was not open.

73, Dave, W9DR

This is another example of how incredible this technology is. I did a little meteor scatter back in the 70's when I lived in IL. The experience was nothing like this. In my day it was 1 minute transmissions alternating on even and odd minutes depending if you were the north or south end of the circuit or something like that. I'll have to look that up since I live in FL now virtually everything is north!!

Ain't Ham Radio just too cool? Bouncing signals off of stardust!! Thanks Dave for the writeup!

73


Monday, June 1, 2009



This is a picture of my signal on the panadapter of the Netherlands WEBSDR receiver. The noise floor is -108 dBm and I am running about -82 dBm. I'm the station at 7010. Notice the key clicks on some of the other stations vs my signal. The good old Flex is pretty well click free. I took this picture as the beta test group was wringing out some tweaks to the CW aspect of the radio and I thought it would be cool to take a pic of how the signal looks and pass it around, as well as listen to how it sounds. Clean as a button. I was checking out the keying and was able to do 60 wpm QSK at 10ms delay with no problem with the present iteration. I never use 10ms delay, I generally use 60ms but it works just fine at 10ms

I moved that little tuner out to the antenna today, and it tunes up great. I taped it up in a big baggie to temporarily water proof it till I can get a something better. It was interesting that the tuner has something like 8000 memories and I generally used just one or at best 4 on any band 80-10. Lot of wasted memories I guess. This evening I was following the grey line across Europe as Europe woke up and made about a dozen DX contacts with this wire, 3 radials and 100W with signal strength between S5 and S9 in the reports. No one had a bit of trouble hearing me. Goes to show you, you can have a hell of a LOT of fun with 200ft of wire flipped up in a tree and strung out on the ground.

73