47 GHz Equipment

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PA0EHG

My 47 GHz system

TX 13 mW output CW
RX Noise Figure about 12 dB

Dish 24 cm prime focus feed

On this page you can see my equipment for 47 GHz

I started building equipment for this band around 1990
At that time there were no other local hams available with interest for this band so I started building two complete TX/RX systems to be able to make a two way contact.

It existed of a crystal controlled narrow band LO with 12 GHz output and a multiplier to 24 GHz, then a doubler using a mixer diode.
Learned from previous designs used for 10 GHz wideband  systems the LO's were 144 MHz offset so that the two systems were able to RX and TX to each other. For switch from RX to TX I just changed the diode bias for best output or best receive performance. Without measuring equipment for this band I optimised these systems by measuring the IF signal on 144 MHz.
When this setup was ready I calculated the possible maximum line off sight distance and decided it was good enough
 to give it a try for a first ever QSO in the Netherlands.

As antenna I used on both systems a 24 cm diameter dish with an open waveguide feed

On 8-3-1992 I made my first test over a distance more than within my shack,
the first system was used at the PA0PLY contest QTH on top off a high chimney, about 150 Metre above ground.
I took the second system with me to a location about 9 km away and we succeeded in the first ever 47 GHz QSO in the Netherlands

The story of this can be found at: first QSO on 47 GHz in PA (Dutch language)

Using this setup I also made the first ever QSO from PA to DL on 4-7-1992 with DC0DA/p

 

When I participated in the Danish Microwave activity week in 1994 and 1995 I became much more interested in 47 GHz and started building some new equipment with much better performance

From Michael DB6NT I received some PCB's to build my new system, based on harmonic mixers for RX and I build a 100 mW source on 24 GHz to double it to 47 GHz giving about 14 mW output on 47 GHz. For that time that was a lot of power. Switching from RX to TX was done using a waveguide 4 port switch.

Also I build a second transverter only a harmonic mixer for RX and TX.
It was my third setup for this band.

 

At this moment I am planning a new system based on modules from Kuhne Electronics and a waveguide switch from OE2JOM

At the end of January 2017 all modules have arrived and I have started building my new system

It should be giving about 0,8 Watt output and an overall noise figure below 6 dB

When it is ready it will look a bit like the system from OE2JOM

 

More experiments for this band to be done

Via Ebay I found this low noise pre-amp, could be usable for 47 GHz. Will need some testing.


 

Also for testing this Doubler-Mixer

 

For my NF measurements


 

And a PA for high output power (3 to 4 Watt) on 47 GHz

 

47 GHz x4 multiplier with 15 to 20 mW output