New 134GHz UK distance record
G8KQW and G8ACE are very pleased to report two 134GHz contacts on Sunday, September 20, 2015
The first from Butser Triangle near the summit of Butser Hill above Portsmouth to Lane End to the SE of Winchester. A distance close to the UK distance record of 17.2Km. Signals were exchanged both ways and a recordings and photos made by G8ACE can be found in the folder here:
https://drive.google.com/folderview?id= ... sp=sharing
G8ACE then moved to a site near Cheesefoot Head increasing the distance to 19.2Km, this slightly exceeds the current UK distance record for the band. Antennas at both ends were aligned using optical telescope and solar reflection from mirrors to pinpoint the exact far ends of the link, as soon as the FT817 IF Rx was turned on by G8ACE a signal from G8KQW/P was heard. However propagation had become somewhat unstable during the course of the site move and the signals were exchanged both ways but only in shorter bursts not as continuous reception. Other difficulties such as high level traffic noise from the nearby A272 made copying more difficult than for the earlier contact. Headphones to be taken next time!
The two 134 GHz contacts were made between 15.00 and 18.00 with Temperature 21C Humidity 67% with a Dew Point of 14.3C
Both sets of equipment built by G8ACE.
Transmitters using DBES diodes multiplying a 33.6 GHz signal x4 from a Broadern amplifier module available on Ebay. One transmitter using a crystal OCXO signal source x1440 disciplined by RDDS and the other a synthesiser running at 2.8 GHz with a smaller x48 multiplication to 134 GHz. FSK modulation employed.
Receivers using diode mixers driven at 23 GHz with synth LO sources at 2.8GHz again multiplied x48 with a 2m IF frequency.
73 .. Ian & John
UK Microwave Group links
http://microwavers.org/
https://groups.yahoo.com/group/ukmicrowaves
Source:
http://qrznow.com/new-134ghz-distance-record/