For a while I had my 1296MHz yagi mounted at a height of just 4m above ground. I could detect the DB0VC beacon in Kiel, about 200km distant, not constantly but every day I made the attempt.
On Easter Sunday I had a local ham help erecting a telescopic mast of 6m. This means that witg a little help from a friend it is possible to make antenna experiments for the higher bands. The rotatyor used is a small AR-500TV antenna rotator, and it works nicely with the small 1296MHz yagi.
The antenna is now 7m above ground (30m ASL), and I could detect a considerable improvement compared to the lower position, in some directions. In other directions there are still obstacles.
At the first test with 7m height 4 local stations were immediately heard, within about 10 minutes of starting operation on 1297.5MHz FM. This is encouraging. The furthest station was near Malmoe, Sweden, at a distance of about 30km, and while my yagi was horizontally polarized, and he used a vertical, we could get some fading signals. I suspect the fading, which came with very regular intervals, was due to some wind turbines along the path.
The beacon DB0VC is now heard a bit more regularly, and today I noticed something that I did not hear with the antenna at 4m. Several aircraft reflections were clearly audible, with the characteristic Doppler shift frequency change.
Today I also got a new station, running at a distance of about 20km, just running 4W, with the ADALM Pluto SDR and a front end with 4W output, running from a balcony with a home made 7 element yagi. Good signals, as we were both working with horizontal antennas.
For all this I used the IC9700. I also have a IC910 with a 1296MHz module.
Future developments:
Two more things are now needed to improve my system on 1296MHz:
- A good vertical antenna as high as I can get it. I intend to use the IC910 with this antenna, and a preamplifier near the antenna, just like with the yagi. Most likely the X-5000 from Diamond, used with a triplexer for multiband operation on 2m/70cm/23cm, with preamplifiers for every band.
- a power amplifier for each antenna/radio system. For the vertical/IC910 I intend to get a relay/sequencer up and running, so I can get about 25W at the antenna. For the yagi, I intend to get a maximum of about 75W at the antenna. I don't have the amplifier for that yet, but I will get one when I can.
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