EQUIPMENT ON SHOW AT TELFORD 2nd
The 76GHz transverter shown left is by Martin
Farmer, G7MRF. As shown here it is not quite complete but was working well
just a week after the rally at Telford. The biggest problems with equipment
at this frequency is (a) mounting the almost microscopic-sized mixer diodes
on the printed circuit boards and (b) obtaining sufficient drive at 38GHz
(this being the subharmonic local oscillator for the DB6NT 76GHz mixers).
The equipment shown to the right is that of Paul,
G0HNW. His knack of putting gear together faster than most other constructors
paid off once again as he was the first of the Northern UK millimetre group
to get his 76GHz transverter working. As a result, others in the group
were able to send him their gear to be checked and adjusted against his.
After all, test gear at that frequency is very hard to come by! Paul's
system includes a highly stable, phased-locked crystal oscillator.
Martin, G7MRF, brought along his stereo microscope
which he uses when fixing the very tiny 76GHz mixer diodes to the printed
circuit boards. The diodes are only just visible to the naked eye and even
a pin head looks big in comparison!
Here the microscope is set up with a (defunct)
diode for visitors to marvel at.