There are currently only 44 SatNOGS ground stations (antenna) worldwide that are defined as being able to receive the 400-401 MHz range.
Putting this out there, after months of observations using my two Yagi antennas that are designed for ~435 MHz (One is an Arrow II Alaskan series Yagi with a DownEast LNA rated for 420-450 MHz) it become apparent that they are quite capable of receiving signals and decoding valid frames from satellite in this low 400 MHz range as well.
So if your looking to extend your reach to UHF satellites (of which there are dozens) in the 400 MHz range, then you could simply revise the frequency definition of your ground station(s) antenna to be that of 400-470 MHz (or similar) rather than the more typical 430-470 MHz.
Some recent examples from my two ground stations for 400 Mhz range
The folks at Boston University are still hopeful for contact since the launch in October. So if you’re in the middle/east part of USA/Canada and can lend an ear for CuPID, it would be much appreciated. No beacon but should tx when passing within range of Boston University’s ground station.
Just a point to watch out for: if you have an omnidirectional antenna and receive regular ‘chirrups’ of data that last for about 2 - 3 hours then disappear, you may just have received a weather balloon passing by. In and around Europe they use the 400 - 406 MHz range as well, which when rising slowly from ground level to 30km and falling quickly back down again can easily be received well over 100km away, even accidentally
Since July 2020, I’ve used the software running on a dedicated Raspberry Pi with a RTL-SDR to track weather balloons launched daily from the NOAA station in San Diego, CA, US and the US Army’s Yuma Proving Ground (Yuma, AZ, US). Tracks are posted in real-time to APRS.FI and HabHub. In the US, radiosondes typically transmit in the 400-403Mhz range.
Thanks Fredric, in fact I already use the software from SQ6KXY. I wanted to point out that there is a conflict of frequency usage here, and early joy at receiving a clear signal may lead to disappointment when you find that you have not tracked a satellite but something a lot closer to earth
USC is still trying for first contact with DODONA since its launch a month ago. Any existing UHF stations willing to redefine their UHF range from 430–470 to the 400-470 range would be greatly appreciated. There are currently 58 SatNOGS ground stations that include the low 400 MHz range, up from 44 stations just three months ago.
Installed a broadband LNA today and extended the frequency coverage in UHF to 400-470 MHz. Will see what can be received. The antenna is a Vertical for lower elevation passes.
