Fun on 10GHz – 1

Over the last 20 years or so I’ve rarely operated my radio equipment away from home. This has changed since I’ve caught the “microwave bug” and got started on the 10GHz band.

My 10GHz setup comprised initially of just a DB6NT Transverter (TVTR) and an IC-706 transceiver for the 144Mhz IF side plus a dish or horn antenna. I soon learnt that in addition to these core items there are a number of additional things that can help to maximise your contacts and results on the band. Frequency accuracy, timing, digi-modes, SDR waterfall display, CAT control etc. can all help, especially if you’re intending to develop your setup for EME operation.

Adding a lot of these ancillary items meant that there were lots of things to remember  when heading out to operate at a portable (/P) location. I wanted a solution that was easy to setup and take-down, didn’t need to have lots of cables plugged in each time and had minimal risk of me forgetting a vital item. I decided that all these additional items should ideally be housed in one enclosure.

Searching for a suitable enclosure resulted in me repurposing an old Dell Optiplex 775 PC case to house all the various bits and pieces. I now have one neat enclosure that houses the following:

  • IC-706 Transceiver
  • PTT break-out box
  • Digimode / CAT interface
  • USB sound card
  • SDR dongle
  • USB hub
  • LeoBodnar GPSDO providing 10MHz and 30MHz output for TVTR and IC-706.
  • 10dB 30W RF attenuator
  • Wilkinson RF splitter
  • Low power Dummy-Load (DL)
  • RF switching relay (SDR / DL)
  • Four-event Arduino Sequencer

The following diagram and photos show the interconnections and end result.

 

At the time the above photo was taken, the rear panel had not been finished. As a result the 144MHz, 10MHz, RX/TX switching and power interconnections were on fly-leads out of the front.

This enclosure with the IC-706 transceiver and ancillary bits is now working really well.  It can also be used as the IF for other bands, for example, 23cms where I use a SG-Lab TR1300 TVTR or with an HF antenna on the lower bands for low power (QRP)  propagation tests which is another area that I’m interested in. The single USB connection to a PC allows for software control of the radio. WSJT-X is a program of significant interest as it provides automatic Doppler shift correction for EME communication. The use of the old PC case has worked out surprisingly well.

What’s next…

  • Currently the interconnections between the 144MHz IF unit and the 10GHz TVTR housing uses three individual cables. I have two multiplexer units to construct which will enable the 144MHz, 10MHz and RX/TX switching all to be done via one coax cable. This plus a (12 – 13.8V) power cable will make for much easier installation, especially if mounting the 10GHz TVTR section at the top of a mast.
  • Improve the tripod table and elevation adjustment.
  • Improve the dish fixings (note the slight lean to one side in the above photo!)
  • Get out and operate /P as much as possible and to try to encourage more use of the GHz Bands outside of contests.

 

 

This entry was posted in 3cms, Blog, EME, GHz_Bands. Bookmark the permalink.