VHF LHCP patch antenna

Hi Bob!
It looks like a fail. Apparently I looked at QFH antennas and saw the left thread or was confused by LRPT acronym.

It is also not clear how I was able to receive the signals. If the antenna is opposite circular (or elliptical) polarized, there must have been suppression.

Thanks for your question. I think I need to fix it and see how it works.

Any progress in creating a constellation of switchable antennas? This patch camera looks like it could be used to tile a dome-like structure. How much of the sky does one tile cover?

As for switching I have little radio experience but for controlling robots I’ve used something like this 16 channel relay module with optical insulation - Botland - Robotic Shop and I wonder if it could be used for switching signal from multiple antennas on and off.

The QFH antennas, when fed from the top, operate in a backfire mode and reverse the polarization. Caused me a lot of confusion when I built them. I am still surprised how well they work especially the UHF (724) one as I built it using some 3mm enameled copper wire recovered from an old power transformer.
Mind you both my receiving antennas have LNA4ALL pre-amplifiers right at the antenna which helps a lot. I have separate antennas for transmitting.

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You could also use the Pimoroni Automation hat for RPi, using its relays to switch proper remote RF relays. See [Automation HAT – Pimoroni](https://the Pimoroni shop here.) They also provide simple niblets and scripts to build into the pre and post observation scripts. :slightly_smiling_face: Can anyone write a simple script for me please?

Sorry for the delay.
My test was based on practice, listening to streaming satellites and taking the position from gpredict as a reference.
With that I roughly estimated the lobe of the antenna. All experimental.


Regarding using a constellation of patch-type antennas in a dome, it is an idea for which I began to test this type of antennas and that is why I am very interested in knowing what is the angle that its lobe covers. This to think how many antennas would cover the entire sky.
Then switch the antennas based on the position of the satellite, which would make this system equivalent to a rotor. But with the advantage that there are no moving mechanical parts, which I understand would have almost no maintenance and would last much longer.
It would be a good alternative to a rotor, except for the difference in gain against a yagi in the rotor, although it can be supplied somewhat by an LNA.


In satellites that are not geostationary, the polarization is not RHCP or LHCP, but it changes all the time with the position of the satellite, which is why there is no difference between using one or the other type of polarization.
If most of the satellites are fixed, and more the Cubesat or Pocketcube, they use as antennas a simple dipole or a quarter wave (which have linear polarization), but the change of position of the satellite with respect to the observation point makes it go changing direction and circular polarization is required to receive it correctly. If it is important to respect the type of polarization in a Geostationary satellite.