47GHz NARROWBAND - USING THE DB6NT TRANSVERTERS
- by G7MRF and G0IVA

 
 
   
Inside the transverter 
G0IVA's Equipment 
 
G0IVA and G7MRF's dish mounted systems 
 
 
G7MRF's dish and tripod system 
 
  To view these photos full size just click on each one in turn

 and now....
OUR FIRST 47GHz QSOS - IN THE SNOW!
7th March 1999

These photos show G0IVA/P, G7MRF/P and G0HNW/P  braving the English winter weather to make their first ever contacts on 47GHz!
 
 
David, G0IVA/P
Merrtyon Low, IO93AD
Martin, G7MRF/P
Merryton Low, IO93AD
 
Paul, G0HNW/P
Bradwell Moor, IO93CH
 
  To view these photos full size just click on each one in turn ....
But before you leave this page, read David Woodward's (G0IVA/p) report of that day's activities...
 
 
From: David Woodward [g0iva@dmwoodward.freeserve.co.uk] Sent: 07 March 1999 17:32 
To: Peter Day, G3PHO Cc: g7mrf@compuserve.com 
Subject: 47GHz Tests 

Today (Sunday 7 March 1999) Martin G7MRF, Paul  G0HNW and myself, David G0IVA ,(assisted by Vinny G7OKU) ventured out to have a go on 47 GHz. The weather at our respective homes before setting out was not very promising, with 
continuous rain but we decided to give it a go anyway! 

Paul set up at Bradwell Moor, near Castleton, IO93CH (SK143794) and Martin and I set up  near Merryton Low, IO93AD (SK040613). Paul has not finished his 47 GHz transverter yet but is able to generate a signal using his 24 GHz gear and a multiplier at the dish feed.  Martin and myself both had complete transverters (DB6NT - Martin's using 1296 MHz IF) - with a best dx so far of about 50 feet! 

After using 24 GHz for alignment, 'MRF and 'IVA were both able to receive 'HNW's signal at 59+. Paul was able to transmit NBFM and crossband 144/47GHz QSOs were completed easily at approx 21 km. 

G0IVA then relocated next to G0HNW on Bradwell moor ('MRF staying at Merryton Low) and and after using HNW's signal to net onto, 'MRF and 'IVA were able to complete on 47GHz two way with 57 signals (SSB and NBFM 
tried) at 21 km. G7MRF could copy G0IVA's signal on open waveguide. At the time of the test,  the weather was very poor with visibility at Merryton Low end down to a few yards and considerable snow/sleet at times - hardly ideal 
for 47 GHz. 

One interesting thing noted was the back scatter from the snow/sleet when 'IVA was listening to 'HNW's signal. The two dishes were beaming the same way,  but spaced about 70 feet apart. The backscattered signal was a similar note to rainscatter signals on 10 GHz but with relatively light snow/sleet at the time. Shielding the main beam of the dish killed the backscatter signal but I could then just hear nice note from 'HNW direct. This initially caused some concern as I thought my LO had suddenly become very rough!! 

No further tests were made as the weather was very poor and some of the higher roads were closed due to snow. 

We will have another go soon to try and extend the distance a bit -preferably in better weather!

 
 
  Full details of the DB6NT 47GHz transverter may be obtained from the following sources:

Design and Construction Article:  DUBUS TECHNIK IV pages 359 to 365

Purchase of Kits and/or assembled modules:

Europe -  http://web.aurecvideo.fr/infracom/db6nt.html

USA -       http://www.ssbusa.com/

Worldwide - Email DB6NT for his excellent microwave catalogue and order form. He now accepts Visa and
                     MasterCard !


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