21/11/22: G4NSJ Worthing 70cm CW Beacon. 432.491MHz. Locator IO 90 TT.
My RS41 Radiosonde has been reprogrammed, by my good friend Roy, to operate as a low power beacon on the 70cms amateur band.
CW frequency: 432.491MHz.
Ident: G4NSJ Worthing IO90TT.
Time interval: 15 seconds.
Antenna: Sirio CX-425 at 30 feet.
Signal reports please to: [email protected]
What is a Radio Sonde?
If you’re not sure what a Radiosonde is, there’s a load of information here.
The photos below show the RS41 Radiosonde (not much to see) now operating as a beacon on 432.491MHz. The beacon was running on a 13.8 Volt power supply, via a Buck convertor to give 3 Volts. However, I now have a dedicated 3 Volt supply, shown in the photo on the right, eliminating the need for the convertor.
RSGB band plan 432.400 – 432.500MHz Propagation Beacons:
A small segment for Personal Weak Signal MGM Beacons at the top edge is available in the guard band. The idea of a beacon is to give some indication of propagation. At UHF, the beacon will be a useful bench mark for comparing receiving aerials.
2/12/22: Beacon now running on a Sirio CX-425 antenna at 30 feet:
Thanks to Roy for the antenna installation (see photo below). Scaffolding gone, the antenna is shown on the right, this is now the permanent antenna for the beacon.
Below is a short video of the beacon received two miles away. Thanks to Roy for the video clip. The beacon antenna was a Watson W50 at 40 feet. The CW speed is rather fast so I’ll be slowing it down at some stage.
11/1/23: Beacon heard 13 miles away:
The beacon was received today in Woodingdean, Brighton, at a distance of 13.5 miles. Below is the view from Woodingdean looking across to Worthing. For once, it’s not raining!
24/11/22: G4WTV Worthing 70cm Beacon now on the air:
Ident: G4WTV IO90SU.
Time interval: 30 seconds.
Antenna: 5/8 vertical.
G4WTV radiosonde beacon and antenna
14/12/22: A radiosonde balloon launch:
Thanks to Rusty Rocket for allowing me to use his video clip. Copyright C 2022 Rusty Rocket: You can find Rusty’s YouTube channel here.
Another beacon due on the air soon:
We’re beacon mad here in Worthing. There’s about to be another 70cm beacon on the air. Watch this space…