When I purchased the small Flexa Yagi antennas some time ago it was the intention to make a compact, not too visible antenna system for 2m/70cm/23cm SSB/CW etc operation. At the time I had chemo therapy, so everything went too slowly, and the project almost died.
This project has now been resurrected, and I got the 3 antennas assembled.
- 4 element yagi for 144MHz
- 11 element yagi for 432MHz (strictly speaking 8 elements, as there are 3 reflectors making a reflector plane).
- 16 element yagi for 1296MHz
The Flexa antennas have very thin steel elements (and a not too heavy boom), reducing the visual impact of the antennas, as I wanted
All these antennas are made for mounting in front of the mast, i.e. "behind" the reflector, so the mast will not interfere with the function of the antenna by blocking part of the elements, especially on the higher frequencies.
Having all antennas front mounted will create an imbalance of the load on the rotator, so I am thinking of making a compromise here: Mounting the largest antenna (the 4 el. for 2m) on one side of the mast, then mount the 70 and 23cm antenna in the opposite direction. This will make the operation a bit more cumbersome, but I think it can be done.
I may add a Moxon Rectangle for 4 and 6m to the system. This is a rather small antenna and will not add significantly to the visual impact.
Further, some small antennas for the 2400MHz and 10GHz band are expected to be added. No parabolic dish there, just some tiny yagi or patch antenna for 2400 and a small horn antenna with a transverter for 10GHz. This is for later, but initially a LNB (frequency stabilized), maybe with a small horn extension will be mounted for 10GHz monitoring purposes.
I will need to mount this on a rotator. No need for a heavy duty one, so I am looking into options.
I intend to mount the system on top of an old apple tree where I have some antennas already.
For SSB/CW (DX) work I have had a clover leaf ("Big Wheel") antenna mounted right on the top of the tree, essentially invisible, and it has provided some DX on 2m.
What kind of performance can I expect from this system.
On 2m, the stated gain of the 4 el. antenna is 7.6dBd. This may be exaggerated, but compared to the old clover leaf antenna I expect to mount the 4 el. 2-3m higher and less obstructed, so I would expect a performance improvement of approximately 10dB over the clover leaf antenna. With a good preamp at the antenna, and also an added PA in the shack I should have a solid performance boost, compared to the current system.
On 70cm, with a stated gain of 10.2dBd the system is a very modest, but some DX activity should be possible.
On 23cm, with a stated gain of 14.2dB (exaggerated?) I would expect some interesting occasional DX activity, especially if a preamp and a PA (25W?) is mounted near the antenna.
On 13cm this system will just be playing around , maybe with some interesting DX in the best directions I have, but I do not expect much there.
On 3cm the system is very modest. I may be fortunate enough to make some DX under excellent tropo conditions, and possibly some rain scatter QSOs.
For the higher (microwave) bands some hilltop operation is probably a much better option, but the capability of some modest home operation is good to have.
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