PD4U
Dutch Amateur Radio Sation

Amateur Position Reporting System (APRS)

I am also active with APRS: Amateur Position Reporting System or also called Automatic Packet Reporting System. Developed by Bob Bruninga, WB4APR. A TRX in combination with a GPS receiver and a packet radio TNC (or APRS software on a PC), amateur radio base stations can transmit their location and/or weather data, and mobile stations beside their location, their speed, direction and elevation via packet radio. Which can then be plotted on a map like the one below, by stations who receive this APRS data. The system works with digipeaters and base stations that upload this received information to APRS servers via the internet. I use the Yaesu FT-7800E mobile transceiver [PD4U-9] or the Icom IC-E90 handheld transceiver [PD4U-7] for this purpose in combination with the Tinytrack 3 from Byonics. The antenna on my car is a Diamond CR627. This is a multiband vertical for 6m, 2m and 70cm. The software programs I use as a base station are AGW Packet Engine and AGW Tracker by George Rossopoylos, SV2AGW. The frequencies used for APRS in the Netherlands are 144.800 MHz and 430.5125 MHz. When I'm active you can see the local activity and DX spots on my local activity page.

Besides sending your signal via local APRS digipeaters it is also possible to send and receive signals via the digipeater of the International Space Station (ISS). The Unproto address (or beacon path) is RS0ISS-3 (zero!). You can also use ARISS (the alias for the ISS aprs digi callsign) in the unproto path. ARISS stands for "Amateur Radio on the International Space Station". The call RS0ISS-4 is reserved for live packet communications with the crew, though this call is also often used for digipeater operations. You can also connect to the ISS because it also has a BBS/mailbox. The unproto adress of the BBS is RS0ISS-11. See PD0RKC's ISS-BBS page on how to operate the BBS. The digipeaters and BBS are in the Zvezda module (living quarters) of the International Space Station and all operate with Kenwood D700E's. See for a detailed description of Packet/APRS digipeating via the ISS AF6DS' presentation (PDF file).

If you want to see what the current position of the International Space Station (ISS) is, or want to see if the International Space Station is in range of your location you can visit the Heavens Above Homepage. Also have a look at the ISS Fan Club to see whether the packet radio digipeater (RS0ISS-3 / RS0ISS-4) and the BBS (RS0ISS-11) are active or not. This great site also offers status reports of the ISS and her crew and has an audio recordings archive and a SSTV picture archive. For the same status information you can also check at KD5QGR's Live Oscar Satellite Status Page where the activity of several other satellites is also listed, and where you can upload your spots of the ISS or other satellites.

On the same downlink frequency as the ISS (145.825 MHz FM) operates another satellite: PCSat or NO-44. The uplink frequency for PCSat is 435.250 MHz. PCSat has a similar page on findu.com where you can see the stations heard/digipeated by PCSat. See: K4HG's PCSat page. The unproto path for this satellite is PCSAT-1, but you can also use ARISS as alias in your unproto path for this bird. So the best thing to do is to use ARISS in your uproto path for the ISS and PCSat (NO-44).

Another satelitte that can be used for APRS is GO-32 or also called Gurwin Oscar Techsat 1B. This satellite operates in 9600 baud however. The uplink frequency for GO-32 is 145.850 MHz for all APRS messages, and for Mic-E position packets only the uplink is 145.930 MHz! The downlink frequency is 435.225 MHz. See also Bob Bruninga's (WB4APR) and Roni Waller's (4Z7DFC) GO-32 APRS operations page at www.aprs.org for further information.

During one of the latest missions of the Space Shuttle Endeavor (STS-127) two microsatellites, called ANDE Active (AA) spacecraft (Castor) and the ANDE Passive (AP) spacecraft (Pollux), were launched from the Space Shuttle cargo bay. The satellites of the Atmospheric Neutral Density Experiment (ANDE) will be transmitting on 145.825 MHz. Castor will transmit telemetry every 30 seconds. Pollux every 33 seconds. Both are transmitting 1200 baud AX.25 packet telemetry. See PA3GUO's site for up to date information about the ANDE sattellites. Also have a look at his video from a fly-over of the ISS over the Netherlands.

 
Messages by PD4U
Local Activity on APRS
Nearby Activity on APRS (findu.com)
RAW APRS Data
Mobile Activity PD4U-9