UHF/SHF

3cm Narrowband

3cm band is the newest of bands for me. in late 2005 i bought a DB6NT 3cm transverter Kit, and was very eager to get up and running on 3cm even though i'm beheind the North York moors when it comes down to getting south to the dx stations!
It took me about a week to get the kit built and tuned up, it certianly was worth the money and worked nearly first time i powered up. The only thing i had got wrong was a couple of diodes used for switching the tx/rx stage, anyway the output measured at work showed up 310mW output which i was pleased with as it only states 200mW on the specs !

The next thing was to bult an antenna, my first attempt failed for some reason. This was a modified sat LNB without the mixer stage and BP filter on the front of a sky mini-dish, just as a pre-amp... Nothing was heard but this might have been down to accuracy in the dish pointing! Next attampt was just with the end of some hardline ut-141 bared off at the ends poked up inside the LNB horn and actually worked! I was able to hear the weak carrier of GB3MLE over 80km away !!

I then built the G3PHO Horn form the appropriate bits of copper plumbing pipe, reducers and couplers, and made my own SMA to waveguide adaptor to match. This proved a much better method and was able to hear the CW keying on the beacon much stronger now also with a 60cm sat dish.

So far the only station i have worked (one-way) was peter G3PHO when he was at pocklington for the contest last year(2004) and he was perfectly audible with me on SSB but unfortunately he could not hear my small signal! (250mW) He was running about 4W into a big dish.

22nd of march 2005 was my next part qso... with G4XUM, i heard his signal from IO83SB 170km away at about rst319, quite surprising to hear a signal on 3cm over that distance, Martin could detect me but i was not readable.

27th March i managed to work G1GEY in SSB for the first time, we have worked CW a couple of days earlier but with weak signals. the 27th was very wet and foggy, ideal for 3cm!

Here are some recordings of Don's side of the QSO...

G1GEY 3cm cw

G1GEY 3cm ssb

Since working Don and Martin i have worked G3PHO on the NY Moors with no problem and have worked Martin again at 5/7 two times in a row on contests(2005), must be a good path!

In May 2006 i have worked my first strong Rain Scater signals on 3cm.. G1GEY (IO94) and G4PBP (IO82)

Here are some recordings of the qso's...

G1GEY SSB

G1GEY CW

G4PBP SSB

DX Worked on 3cm Since 2005

Updated August 2008

Update September 2007

I now have re-built my 10GHz Narowband setup into a new box, i have also added a 10W amplifier and G8ACE OCXO for beter stability.

Here are the Photo's

Front and Back

Box mount and transition to Penny feed.

Transverter / Amp / C/O relay / Isolator/ Sequencer /

G8ACE OCXO ** removed to take photo **

10W Amplifier

At the beginning of september the Manchester 10GHz beacon came on air from it's permanent location and much to my surprise it is audible all of the time!! distance is just over 100Km but straight through the Pennines! Signal is normally 41S due to the path but constant and very succeptable to rain scatter, regularly up to S9 for hours at a time! Rain scatter is seen on GB3MLE on 10GHz (at 80Km) but only at very weak levels in comparison.

In the october 10GHz contest i managed one qso with G8KQW/P in IO82 and it was easy work on ssb, mostly down to the new amp :-)

New 10GHz system - July 2009

Video clip of my new setup using a Zone 2 SKY Minidish

GB3XGH Rain Scatter audio clip.

Here is the path plot to GB3XGH on 10368.810:

M0DTS.co.uk