Ooooops, I put out some defective advice for now on the PicoAPRS: https://www.hamradio.com/detail.cfm?pid=H0-015928 and want to correct.
I took the plunge and got one in my grubby little hands. Yeah, it's small but one lousy kicker here. It will only update the position once every 10 seconds at a minimum so I can't recommend it for now for rocket tracking.
The Beeline GPS ham trackers beacon once every 5 seconds which is likely the maximum that can reliably be done with APRS. Of course the Beeline GPS trackers can write more frequent position updates to memory for download
after recovery.
I have an email in to the developer DB1NTO to see if that can be changed with a firmware update. I believe it could be done simply.
I did do an APRS ground test with customizable hardware using a computer and a handitalkie and got position beacons out once every 3 seconds that were decoded properly when I did a range test.
One might say that the NMEA trackers (EggFinders,MW T3's and such) do 1/sec reporting. Yup, they do but I haven't been able to get 1/sec recovery of positions plotted reliably with the EggFinders on real flights though better antennas lead to better recovery of the NMEA strings. Enough positions are received though to pull off recoveries. I haven't lost an EF tracked rocket yet and have had quite a few. (Haven't flown a T3 yet but it outputs 250mW so it might
have a different outcome.)
The only 2 meter band APRS tracker candidate is the Sainsonic AP510. It can be tuned off the national APRS frequency of 144.390 Mhz (I use 144.600 or 144.800) and can be set to beacon once every 5 seconds.
It's bigger and amenable to 4 inch diameter von Karman nosecones. The higher the ratio (5:1) the better so's to be able to use a longer more efficient antenna. Plus at 1 watt output the ground footprint should be
larger on the ground as opposed to 900 Mhz trackers. Sorry for the missinformation. Kurt
I took the plunge and got one in my grubby little hands. Yeah, it's small but one lousy kicker here. It will only update the position once every 10 seconds at a minimum so I can't recommend it for now for rocket tracking.
The Beeline GPS ham trackers beacon once every 5 seconds which is likely the maximum that can reliably be done with APRS. Of course the Beeline GPS trackers can write more frequent position updates to memory for download
after recovery.
I have an email in to the developer DB1NTO to see if that can be changed with a firmware update. I believe it could be done simply.
I did do an APRS ground test with customizable hardware using a computer and a handitalkie and got position beacons out once every 3 seconds that were decoded properly when I did a range test.
One might say that the NMEA trackers (EggFinders,MW T3's and such) do 1/sec reporting. Yup, they do but I haven't been able to get 1/sec recovery of positions plotted reliably with the EggFinders on real flights though better antennas lead to better recovery of the NMEA strings. Enough positions are received though to pull off recoveries. I haven't lost an EF tracked rocket yet and have had quite a few. (Haven't flown a T3 yet but it outputs 250mW so it might
have a different outcome.)
The only 2 meter band APRS tracker candidate is the Sainsonic AP510. It can be tuned off the national APRS frequency of 144.390 Mhz (I use 144.600 or 144.800) and can be set to beacon once every 5 seconds.
It's bigger and amenable to 4 inch diameter von Karman nosecones. The higher the ratio (5:1) the better so's to be able to use a longer more efficient antenna. Plus at 1 watt output the ground footprint should be
larger on the ground as opposed to 900 Mhz trackers. Sorry for the missinformation. Kurt
