Showing posts with label 5665 MHz. Show all posts
Showing posts with label 5665 MHz. Show all posts

Thursday, 11 April 2019

6m RBTV Outing to Titterstone Clee

Having failed to make a 2 way QSO with G8GTZ/P on 50 MHz RBTV from the Tump due to his PA issues we decided to try again over a longer path from Walbury IO91GI to Titterstone Clee, IO82QJ. It would also be an opportunity to try the 5665 MHz FMTV system. Path profiles looked good for 6m , but a bit iffy on 6cm

Approaching the site I was surprised to see snow on the ground! The 6m gear was assembled and Noel was a good signal on NBFM, although there was deep QSB. Transmitting 50 W of DVBS to Noel he could not quite get a picture decode. As I was using my Portsdown 2019 system, which is Limesdr mini based, I had the option of running DVBS-2 transmissions, which supposedly gives the system an extra 2 dB capability. Switching to that mode allowed Noel to get a decode.


Noel then transmitted around 10 W of DVBS-2 back to me. The minitune receiver could not quite get a picture , but I left it running while on a long meander around the site trying to find cellular coverage, and when I came back had captured his  test card. Two way QSO of 140 km completed for a new UK record.

I then assembled the 5665 MHz equipment, with its 2' dish and FPV modules with an 8W Fujitsu amp. The FPV Transmit module needed a 20 dB attenuator to avoid overdriving the Amplifier. Talkback was on 6m FM. Noel couldnt see my signal, and I couldnt see his 3 W, with the exception of a 15 second period, assumed to be aircraft scatter where his signal was identified. Partial success at least, perhaps confirming the predictions were correct.
G8GTZ/P

G4FRE/P