Wednesday, December 31, 2014

Introduction to FLDIGI on January 20th at 7:00 PM

The TDRC will be presenting "An Introduction to FLDIGI" on January 20th at 7:00 PM at the Tulsa Amateur Radio Club meeting.  Meeting will be a University of Tulsa's Keplinger Hall.  It will be an excellent opportunity to find out more about the opportunities to operate digital modes using the FLDIGI suite of programs.

No FLDIGI Net January 1st -- nets will resume January 8th

There will be no weekly FLDIGI net on January 1st in observance of the holiday.  Nets will start up again on January 8th.

Monday, December 22, 2014

Python code for Satellite Tracking.

I've done some elementary Python stuff on the Rasby and in Windows but I need to pick up this "rabbit trail" sometime soon.

like most Python code, this looks super-easy. ... almost magic....

de Scott / KD5NJR

Saturday, December 20, 2014

No FLDIGI net December 25th

No net this upcoming Thursday because it is Christmas.  We will resume again the following week.  Everyone have a Merry and safe Christmas!

Satellite tracking on Raspberry Pi

Something worth trying, even though I haven't had the chance:

From: LA3RIA
Type/Status: BF
Date/Time: 05-Dec 17:41Z
Bid: 1969_GB7COW
Title: Gpredict

R:141205/1824Z 4253@N9PMO.#SEWI.WI.USA.NA BPQ1.4.62
R:141205/1824Z @:JE7YGF.03.JNET7.JPN.AS #:30366 [Ichinoseki] $:1969_GB7COW
R:141205/1823Z @:7M3TJZ.13.JNET1.JPN.AS #:43652 [Sayama] $:1969_GB7COW
R:141205/1822Z @:CX2SA.SAL.URY.SOAM #:12999 [Salto] FBB7.00e $:1969_GB7COW
R:141205/1912Z @:VK2DOT.CC.NSW.AUS.OC [Niagara] #:33900 XSERV500f
R:141205/1741Z @:GB7COW.#44.GBR.EURO #:1969 [264114] FBB7.01.35 alpha

To  : RPI@WW

To  : RPI@WW

Using the Raspberry Pi and GPredict software to track Funcube-1 (or many other) satellites

start up a terminal window (LX Terminal). Then type
sudo apt-get update
sudo apt-get install gpredict

The Pi will then download and install the GPredict software for you and return to the commaind
once it has finished.

To start the software up, from your terminal window, simply type: gpredict
OR: main menu >> Run >> Type gpredict
The software will then start. You need to do a little configuration to tell the program where
you are 
(the default is Copenhagen where the author lives!).

Happy tracking! 
73 de Mushtaq

MFSK-32 practice from a "Big Gun"

See message below. These MFSK-32 radiograms are run every weekend:

VOA Radiogram this weekend (December 20-21) contains VOA and RFE/RL news items in MFSK32, including six MFSK32 images. That's almost like television.

Details at

VOA Radiogram transmission schedule
(all days and times UTC):
Sat 0930-1000 5910 kHz
Sat 1600-1630 17860 kHz
Sun 0230-0300 5745 kHz
Sun 1930-2000 15670 kHz
All via the Edward R. Murrow transmitting station in North Carolina. 

Wednesday, December 17, 2014

Another Thursday night net

Another Thursday night net: Starts at 9 PM. Questions or need help? Call for AE5ME or KD5NJR on the Broken Arrow 444.000 repeater. KD5NJR will be on 7.036 MHz running PSK-250 on USB. AE5ME will be on 2m : 145.03 MHz FM Both will be PSK-250 at a center frequency of 1500 Hz.

625 miles on 1 watt. Very Cool.

Here's a sample of what FLDIGI can do for QRPP (low low power), from Mike AE5QL: Hey guys, Well I think I validated the softrock this evening. I just had a 5 minute QSO with Kevin, KK4YFK in Frankfot, KY. Jeff, I was running the 1 watt with everything set the same as when we were testing on Monday. Kevin was calling CQ and I thought I would try not expect him to hear me. He came right back and we discussed stations and the Softrock. He was running an FT-857 at 25 watts that is about what I usually do, and he gave me an honest 429. He said that he could not see me in the water fall but he had a good copy on my text. 625 miles on 1 solid watt. Very Cool. 73s Mike, AE5QL

Sunday, December 14, 2014

Latest results from FLDIGI testing/net

We conducted another "dual band" net last Thursday (December 11th). There was one HF station on 7036 (AE5QL). He and Scott were able to achieve good communications on 5 watts on PSK250. However, once he dropped to one watt, AE5QL couldn't be copied at either Scott's or my location. Further followup this weekend seems to confirm that about 3 watts is required for a reliable connection between AE5QL "in the Mingo valley" and other stations in Broken Arrow 5-6 miles away. The other side of the net was on 145.03 Mhz FM. KB6LZJ was able to connect with me and received all the bulletins I sent out. He does have a weird situation in which FLAMP doesn't always connect up to FLDIGI and may miss bulletins as a result. We'll be following up on that to figure it out. One other station on a Baofeng UV-5R was not able to reach us on FM. He will be trying again next week. We switched over to 145.03 Mhz SSB and it would appear required power dropped lower than what is required on FM. Might be worth some later experimentation to compare to our HF results.

Monday, December 8, 2014

BeagleBone Black as alternative to Raspberry Pi

Happened to have an opportunity to try a BeagleBone Black in a work application (worker timestation).  Turns out that the performance web browsing is MUCH faster than the Raspberry Pi.  Web pages are loading and rendering 2-3 times faster than the Raspberry Pi in the Chromium web browser.

I don't know that it will be a speed demon for floating point operations or graphically intensive applications, but certainly something to consider in your tool belt for certain applications that need a little more speed.

Some benchmarking to consider:

Thursday, December 4, 2014

Thursday Night Net : 2100 CT. 145.03 Mhz ; 7.036 MHz

Monitor the Broken Arrow 444.000 repeater to coordinate / help. KD5NJR will be on 7.036 MHz running PSK-250 on USB. AE5ME will be on 2m : 145.03 MHz. 73 de Scott KD5NJR

Wednesday, December 3, 2014

PSK instead of AFSK (1200 baud packet)?

Check out the presentation at

Interesting observations on how to conserve spectrum by replacing conventional packet with PSK modes.

Note that they are using SSB instead of FM (to save spectrum) and AX.25 over PSK.

Our BPQ32 software actually uses ARQ over PSK, so I will be doing some testing to see the advantages/disadvantages of that versus conventional AX.25 frames.  My gut feel is that the ARQ is more efficient, but would like to verify with tests.