I have got myself a new transceiver. For the microwave band I am now testing a new IC-905 and the 10GHz module (transverter).
This rig runs 10W on 144,432 and 1296MHz, and 2W on 2.4GHz and 5.7GHz, and 500mW on 10GHz.
It has 2 mast mounted modules, one transceiver for 144,432,1296MHz, 2.4GHz and 5.7GHz, the other converts the 2400MHz band to 10GHz. Everything is controlled fro a control module that resembles the IC-705, and it feeds 40V up to the modules via PoE (Power over Ethernet), and the rig has a common N-connector for 144,432 and 1296MHz, and separate SMA connectors for each of the higher bands.
The system has a built-in GPS for controlling the reference frequencies.
Time to do some tests, I started a few days ago. First, get it up on a tripod in the living room, and the tests could begin.
The very first tests was checking that the GPS system worked, and even indoors it would lock. I should be right on the frequency in the display.
I have not yet tested the 144 and 432MHz parts, but I set up a small 12 elements yagi in my living room, just 0.5m (about 2 feet) above the floor. To my surprise the OZ7IGY beacon located behind some hills about 20m higher was clearly audible. First successful test done!
I tried setting up a 2400MHz yagi (16 elements), and I was not surprised that I heard nothing from OZ7IGY. I could hear noises that I suspect came from the local wireless network.
Using a PCB log-periodic antenna, exactly the same happened on 5760MHz.
On 10GHz I set up a synthesizer generator in the house, and got a strong signal, using a PCB patch antenna array (16 patches in a 4x4 array). The transmit side was tested using my QO-100 receive setup, and worked nicely.
Today it was time to get out in the field. Temperature in the 15-20C range and some sunshine, it was a beautiful day to get started. I drove the system a few km from my home, just a bit up a hill, but not to the top (no driving permitted there). It took about 1/2 hour to get it up, and the test could begin, using the exact same antennas as in the indoor test.
The 1296MHz antenna was about 2.5m above ground and turned towards OZ7IGY. Signal was booming in, above S9. RX Success!
The 2400MHz antenna was very low above ground, about 70cm. The signal from OZ7IGY was a solid copy, though not very strong. RX Success
On 5760MHz the beacon was all but inaudible. I thought I could hear a signal tuning around the frequency, but I was not 100% sure, so I say no reception.
On 10GHz no reception (not surprising).
On 5.7 and 10GHz the cables used were some surplus semi-rigid cables with angled SMA connectors, so I suspect high losses, but the test had to be made. I am sure I could have gone to a different location with no hills in the way, and get reception, but I stayed because there was one more test to do.
I called on the local FM frequency (1297.500), and as I had announced my activity locally, there was immediate calls from 2 stations in the Copenhagen area and one in Sweden, just across the water. The SM7 station was 43km away and a solid S9, with a fairly unobstructed path.
One of the locals alerted a station in the other direction where there are some obstructing hills. Call made and good signals at 43km in the more obstructed path.
This was "first light" for my IC-905, and I am satisfied with the results. I can see many possible improvements to the system, so I have quite some work to do with the mechanical part of the portable system. Mainly better antennas for 2.4, 5.7 and 10GHz, and a better way to fix those antennas to the tripod.
At today's test the 1.3 and 2.4GHz yagi antennas were mounted using gaffer tape, so there is already some hardware that I will need to go get, some holes to be drilled, so I can mount those antennas to the mast in a more secure way. As a first test, it was good enough, though.
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