W2MMD Satellite Blog

Select satellite in Next Pass list Antennas - 70 cm on SDR; 2 meter on 847; preamp on Rotator set to track Satellite Doppler tracking set SDR set to WFM SDR recording set if desired FOR WISP ONLY: HW Serial port configured for COM6 - Login, change Port Name to COM6, URL and Port to 8100 and press Create COM: Soundmodem HS running Output = Rigblaster output Input = VAC line 1 UISS running Via PFS3-1 Beacon on (?) 847 set to 9600 baud - menu 23 847 tone encoder OFF (TONE button right of knob) RigBlaster set to VOX RigBlaster XMIT level set at 50%  SoundCard audio level set for 12:00 Rigblaster sound card set up 48000

On an otherwise lousy day I got the FalconSat telemetry decoder working. It's a 2-step process - you process the telemetry with the Soundmodem HS and the AGW-KISS program, which will write the telemetry files into the c:\HamTemp\Falconsat folder.  You then point the Telemetry decoder (see the Start menu) to that file and it will decode.  Here's how the telemetry looks on the AGW-KISS program:     Here's how it looks decoded: 

Backups aren't handled by the Windows 7 program. Instead they're handled by the Seagate Toolkit software that sits in the system tray. Backups are continuous.

So after a little more research I found that WISP isn't the only program that can read the Falconsat data. UISS will also work using the 9600 baud modem. Here's how it looks: Unfortunately transmitting isn't as easy - you need to pipe the audio into the packet input port on the 847, and we don't yet have a cable to do that nor do we know how to set the RigBlaster to use that input instead of the mic. More research to do. 7/31/18 - Here's a great reference: http://aprs.org/PFS3.html Here's much more on setting up the Soundmodem and other stuff: http://www.microsofttranslator.com/BV.aspx?ref=IE8Activity&a=http%3A%2F%2Fwww.qsl.net%2Fpy4zbz%2Ffalconsat.htm 8/2/18 - be sure that the model settings are like this: The whole picture should look like this: More WISP info is here: http://www.ne.jp/asahi/hamradio/je9pel/wispinsv.htm Old TLE: FALCONSAT-3 1 30776U 07006E 17265.88227951 .00002651 00000-0 83127-4 0 9998 2 30776 3...

We want to build an Arduino-based antenna switch that will sniff the CAT commands sent to the radios and switch the antennas automatically based on the freq sent to the radio.  Here's the start of a blog and some reference articles: https://github.com/pavelmc/FT857d https://g0wfv.wordpress.com/2017/06/19/how-to-program-or-cat-control-your-rig-with-an-arduino/ CAT library: http://ve3bux.com/?page_id=501 This looks like a complete project: http://iz6ndw.blogspot.com/2012/01/arduino-radio-cat-interface-for-antenna.html 7/18/18 additional thoughts Implement the CAT with a Y connector on the 847 serial cable. We only need to read the freq on one radio, and it's easier to get to the CAT cable on the 847 and connect the other connection to the Arduino Use an Arduino Mega because it has multiple serial ports.  We'll pipe the CAT signal to the Arduino and it will repeat it out a serial port to the 847. Also need to feed the CAT from the 847 back to PST Rotator....

Copying the 9600 baud telemetry signal from Falconsat 3 has been a objective ever since we set up the W2MMD satellite station. This satellite was built by cadets at the US Air Force Academy and was turned over for ham use after its military mission was complete last year.  Its primary communication method is 9600 baud GMSK telemetry, and it also has a store-and-forward BBS system onboard. Unfortunately it's in a low-latitude equatorial orbit so the elevation at our QTH never gets above about 40 degrees.  For months I've tried to copy it but couldn't get it to decode using the UZ7HO modem. Adding the 70 cm preamp at the antenna in June brought up the signal significantly but I still couldn't decode it on Field Day. Then tonight I made one adjustment and the signal came slamming into the modem, and out spewed a barrage of coded telemetry and other packets at 9600 baud. See the signal strength below along with the modem output that was piped into the AGW KISS ...

Not specifically satellite-related, but I was playing around with this radio and zoomed down the bandspread on 2 meters to see that it can cover more than the whole 2 meter band! Check out the waterfall below.

If you're interested in satellite operation and would like an easy way to see which satellite passes are upcoming, a pretty cool app is GoSatWatch.  A video is at https://www.youtube.com/watch?v=eKNC4ZoiEic  and the program is at https://itunes.apple.com/us/app/gosatwatch-satellite-tracking/id300546718?mt=8 . This will show the current positions of the satellites that you've selected along with pass predictions well into the future. It will also alert you to an imminent pass. It's a $10 download but worthwhile for any satellite buff. (Thanks to Jim, N2GXJ who recommended the Heavens Above app, which is also good)

Below is a description of some early experimenting in making the W2MMD satellite station, with its excellent location and antennas, available to club members from their homes or other locations. A few of us are informally working on this project, but there's plenty of experimentation to be done, and plenty of room for others to join in. If you're interested in cooperating on this project, post a comment on this blog or email me at jon at pearcefamily dot org. Here's some initial research into remoting access to this station.  We initially tried using a simple Windows Remote Desktop from within the clubhouse, but that seemed to crash the SCR Console program, plus we were concerned with the lack of bandwidth being a problem transferring the moving SDR image. So we decided to move to creating a VPN connection and finding client/server options for the SDR Console and PST Rotator programs. Below is how to set up the SERVER connection. PST Rotator has a client and server co...

Once again the Russian crew transmitted SSTV pictures from the International Space Station. I left the W2MMD satellite station running with the tracker software set to track the ISS, and the MMTV SSTV program running to capture the images from the SDR radio. Below are some of the better images. On a high pass two images can generally be copied; on lower passes it depends on where the image transmission is at AOS.  Sometimes we can get a whole image; other times only the end of one a the beginning of the next. There's usually about a 90 pause between images when the carrier is dropped, so it's easy but incorrect to assume that no images are being transmitted.  When these passes occur, be sure to listen for the entire pass.