Using space based digipeaters this weekend I had a couple of firsts. One was successfully having a packet digipeated by PSAT (Parkinson Sat – NO84). This is a 1.5U CubeSat launched in 2015 carrying a APRS transponder and a PS31 experiment.
I’ve heard this satellite before, but yesterday I had a shot at sending it a packet, I heard it digipeated, but didn’t receive it back well enough to decode it. I waited 30 seconds or so and had another shot with the same result.
With a long weekend, and a major project at work behind me, I had a tiny bit of breathing space to play radio this weekend. What I should have been doing is putting in a couple of hours on the AllStarLink for my club (currently at about 30% finished). What prevented this was a new toy scored second-hand from eBay that arrived this week – a Kenwood TH-D72A handheld.
I grabbed this off eBay, the main attraction being it’s APRS capability, including: built in GPS, stand alone digipeating, and the ability to plug it into a PC and use it as a TNC. My first big plan for this, since I’m miles from anywhere, was to use it to get my staion on the ARISS map by having it digipeated by the International Space Station
The enterprising ex-secretary of my club, Brian VK6TGQ coordinates an “experimenters net” most Sunday mornings in Bunbury wherein different aspects of Amateur radio are played with. Over the last month or so they have been experimenting with sending Slow Scan TV over 2m simplex. From this distance I have not been involved in this apart from occasionally joining them on the IRC channel to see what they are up to.
The equipment to do this can be pretty basic. They started out just with an app on their phones, to transmit, the app loads the image and plays a series of tones (FSK) as each line of the image is transmitted. If you don’t have a cable into your transmitter, you key the transmitter and hold the phone speaker up to the mic. A similar arrangement is possible for receive – the phone is left near the transceiver speaker and converts the tones (and any nearby noises) back into an image. Crude, but results are possible. A much improved result can be obtained by connecting the transceiver to the decoding device (usually a computer tablet or smartphone). Continue reading