Microwave Activity

When it comes to microwave frequencies I am very much a beginner.


I define microwave frequencies as all frequencies above 1 GHz, so the first (lowest) Amateur microwave band is the 1296MHz (23cm) band.

I have done some activity on that band about 30 years ago, with output power limited to 3W (probably <1W at the antenna) with a transverter.


I have some (30 years old) experience with tropo propagation on 1296MHz, and a little bit of recent reception experience with listening on 10GHz with very simple means.


30 years ago I did manage to work 9 DXCC countries with less than 1W at the antenna, a 65 elements yagi. Best DX was Switzerland, so I am not complaining, at all.


First (baby) steps.

Reception experience:

When the Es'hail 2/QO100 geostationary satellite switched on its amateur radio transponder I realized that reception of the satellite downlink on 10GHz was relatively simple (The internet is quite useful, isn't it?). A PLL controlled standard Low Noise Block Converter (LNB) converts the 10GHz satellite signal to approx. 739MHz, and I have an SSB/CW capable receiver for that frequency.

After quite some work aligning the 60cm dish I was able to listen to the downlink.

I had heard about rain scatter signals on 10GHz, so one day with heavy showers more or les inside the beam of the dish, I decided to listen for beacons in the terrestrial narrow band segment on 10368MHz, and sure enough, the closest beacon, OZ7IGY (26km) came in with a fairly strong hiss-like signal, consistent with rain scatter.  Tuning around in the beacon band, I found another beacon: OZ9GHZ. I had heard that it existed, but did not know its frequency. (Now I do ;) ).

Later I realized that OZ9GHZ was barely audible at all times, coming in and out of the noise, evenwith the dish pointing 25 degrees up. Encouraging. I tried setting the LNB on a different dish and point it towards the horizon between two houses, and voilá, OZ9GHZ as pretty strong.

The beacon was even audible sometimes, without the dish, just the LNB feed horn.

OK, another LNB went into the mast, and the beacon is now essentially continuously audible here. "Look mom, no dish!" ;)

This is encouraging.

OZ7IGY, however, even if it is closer, is not audible with this simple set up, probably because the landscape is against me in that direction, rising 20 - 30m within a few km.


As usual, links become active when there is content.


30 years ago I started with a transverter delivering less than 1W at the antenna.

Later new equipment arrived:

TM-741 with 23cm module for FM This has been in limited use

TS-790 with 23cm module for all modes. Not much used.

Some modules and preamps lying around, that should be used

Some small (yagi) antennas, and verticals.

This should be sufficient for getting re-started on 23cm.


Modules, with which it should be possible to build a QO100 uplink TX converter and/or a full 432MHz/2400MHz transverter, (only controller boards for the synthesizer boards are missing yet, but on the way).


Nothing yet


Nothing yet


Some PLL LNBs, suitable for reception on 10GHz.

Some HB100 modules, originally Doppler radar modules, suitable for a low power wideband FM transmitter

Some old waveguide system equipment, including a DRO transmitter

Some (Qualcomm?) modules, likely useable with modifications, for a transverter with 0.5 - 1W TXout

Some horn antennas and a few parabolic reflectors

This should be sufficient to get started with some experiments.


Nothing yet, but some Doppler radar modules are on the way. They *may* be useable for wideband FM

Last Update: OZ9QV, 2019-07-20