The Club is presently running a construction project for its members based on a ‘skeleton’ kit by Hans Summers, G0UPL. The kit, known as the ‘Ultimate2’, is a self contained multi-mode WSPR and QRSS beacon transmitter capable of automated transmission of various weak signal modes.
|Assembled in G3VJM Box
Worldwide propagation is possible with just 300-400mW RF power on the HF bands. The U2 was initiated as a Club project by Peter, G4FYY and twenty-eight club members are presently ‘signed up’ to construct the U2. So far, three beacons have been completed (M0WID, G4FYY and G3RMK) and several more will follow soon. Goto http://wsprnet.org/drupal/wsprnet/map , scroll down to the area below the map and type in your search parameters to see the WSPR activity for any particular station.
WSPR transmissions are synchronised to UTC and while the U2 features an internal clock for this purpose, time-keeping does inevitably drift. As an alternative to the internal clock, the U2 may be synchronised to an external GPS module as a time reference. David, M0WID located a source of low cost iTRAX100 GPS modules and antennas on eBay. Reg, G3RMK then purchased the whole lot (28 in all) and Peter sourced a similar quantity of GPS antennas from another eBay seller. In both cases, we were able to negotiate good discounts for quantity.
Adrian G3VJM has recently produced 22 ‘Acilliary kits’ for the U2, coprising pre-machined cases (to take the LCD display), switches and connectors plus a small PCB for the iTRAX100 GPS module (not shown). This will enable all constructors to complete the project to a uniformly high standard, irrespective of individual construction experience.
The project is proving to be a great success. A vote of thanks is due to Hans, G3OUL for his support to CARC undertaking the project. Hans gave a SKYPE presentation to the Club at the outset and has taken an active part in the volume of email correspondence since. Version 2.02a of the firmware is now available, incorporating feature changes suggested by constructors.
14 June 2013