144MHz Beacon IQ0OS upgraded
Last weekend we have installed a new transmitter for the IQ0OS/B beacon, now it sends the id on CW and PSK31.
Power output is about 5W on PSK31 and a bit more on CW.
QRG: 144.461
LOC: JN61DR
ANT: 2 x hentenna stacked for omnidirectional pattern, horizontal polarization
Any report on the ARI Ostia Webpage is very appreciated.
iw0ffk 
11 March 2014 at 15:22
Looking to build a hentenna in the same configuration, How well does it work? Any problems with it?
Thanks Tim AK4YW
12 March 2014 at 07:51
Hello Tim, after 3 years no problem at all. It was built with hydraulic chromated copper pipe (those of the sinks…). The two antennas have been tuned separately. The delay line for the phase shift and the impedance adapter has been made with coaxial cable.
Here you can find some report and a coverage map of the beacon: http://goo.gl/KNdoau
12 March 2014 at 13:18
I’ve only been a ham for a little over a year and I’m still learning and experimenting with making antennas. I have already made a single hentenna, but haven’t installed it yet. Then I saw the picture of your dual antenna. I wondered if they were simply attached at the same read point, but I can tell from your answer that I have a little more research to do before I try it. Thank you and 73. Tim AK4YW
27 January 2016 at 02:40
Can you tell us some details of the phasing line?
27 January 2016 at 14:59
The antennas are feeded with 90deg of phase difference. After the coupler, one of the two coaxial cable is a quarter wave longer.
27 January 2016 at 18:14
Thank you. What was the theory for the 90 degree feed offset? What would have been the problem with the two 50 ohms impedances in parallel at 0 degrees, other than impedance matching? I understand why to do this for a circular polarised antenna, but I would be interested to understand why you did it here. Very clever use of the hentenna! I use them on 40/80/160m
28 January 2016 at 08:33
Well, the theory is how you can couple two antennas to obtain more gain or, in this case, to modify the radiating diagram. The goal for the beacon was to obtain an antenna omnidirectional and horizontally polarized. If you feed directly the two hentennas, without transformer and 90° delay, you’ll have swr 2.0 and a non-omnidirectional lobe. I suggest to simulate it with MMANA or 4NEC2 to see what happens. Congrats for your BIG hentennas.
11 November 2017 at 21:42
I tried making the antenna wider to get 100ohm, and then directly parallel two at the fedpoint. This worked very well. Very slight bend on an element to get better than 30dB RL.
12 November 2017 at 08:34
Vy good, by making the antenna at 100 Ohm you don’t need the impedance transformer, but in order to have an omnidirectional radiating diagram you need to feed them with 90° phase difference.
Try with a simulator.
12 November 2017 at 08:45
Ha! It is a big job to put all that into a simulator. Do you have a simulator file?
17 November 2017 at 14:02
Hi, I’ve found in my old hard drive a simulation of the double crossed hentenna. It’s for 70cm band, the idea is the same. The simulator is MMANA-GAL. Here the file: https://goo.gl/baS7WN