Upcoming test of 3 types of UHF antennas

Yes, I have noice and local interference on 70cm band, there is not much I can do about this. But I have done several different tests with the Eggbeater antenna and I think it is faulty.

Can you try making my QFH?

https://www.ea5wa.com/antenas/antena-qfh

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Oh, sorry I didn’t realized you are talking about UHF…

Yes it’s UHF I’m testing now. My VHF antenna works very good. :slight_smile:
I have tried to make a QFH before, without any success…
Next test will be with a small UHF yagi, fixed elevation and azi mount. Stay tuned for results!

So, testing a small UHF Yagi now, fixed elevation, for my station. Got decodes now, so I think this will be my solution, at least the strongest sats can be followed at some passes (not all of course).
Will also try to stack two yagis.

Continue to use fixed Yagi. It seems that my broadband LNA, not filtered, is having huge problem with interference so I’m continuing testing with the LNA switched off.
Soon I will test to with two stacked yagis.

Why don’t you give a try to QFH antennas?..

https://network.satnogs.org/observations/3066421/

Bugsat without any LNA

73’s from EA5WA Juan Carlos

Yes, that is impressive, I see a lot of stations using omni antennas on UHF and get decodes. I have a bad QTH and very strong interference so it seems I need the gain from Yagis…

Hi Lars,

have a look at our UHF Eggbeater antenna we use at DK0SB in Bochum https://network.satnogs.org/stations/1663/

https://network.satnogs.org/observations/3058204/
LUSAT with its continuous carrier allows you to compare easily.

We also use VHF Eggbeater with outstanding performance… the only Antenna which can beat it is the TA-1 Antenna we use on the APT station!!!
The Eggbeater does have more gain in higher elevation, so ground noise is very well suppressed at very low elevation…
The TA-1 is more wideband and I have a run a lot of comparisons. I’m surprised how well the TA-1 works in a silent environment. We have added a 137 MHz cavity filter and APT works like a charme…
We will be adding Higain VHF/UHF antennas with Rotator later this year…

73s Peter

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Hi Peter,
thank you for info. Impressed by your UHF Eggbeater, that is way much better results then I got with mine. My VHF Turnstile antenna is performing very good (from Vinnant Antennas) so that one I’m going to keep.

Thank also for LUSAT info, I will schedule that satellite for my tests.
73 Lars

You say the only antenna can beat the eggbeater is the TA-1 Turnstile… Had you tested the QFH?

https://network.satnogs.org/observations/3045483/

Received with UHF QFH without LNA

You say the only antenna can beat the eggbeater is the TA-1 Turnstile… Had you tested the QFH?

I was speaking about VHF here, there is no TA-1 or similar available for UHF.

But if I compare https://network.satnogs.org/observations/3074174/, the UHF Eggbeater preforms very well, even at lower elevation as expected.

and here a comparison of UHF QFH (left) against UHF Eggbeater (right) on almost identical overhead passes with LUSAT

73 de Peter

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A bit hard to compare when the waterfalls scaling is so different.

Is it?
Admittedly I don’t know the exact details of the passes there, but from those two waterfalls I can see that the eggbeater appears to have a higher SNR in the middle of the pass, and received lower down to the horizon.

The QFH does have a higher noise floor, which could be from antenna placement, or an antenna design which isn’t rejecting local noise well enough. It could be that the reason its not receiving the sat signal down to the horizon is its being obscured by local noise.

Where do you see a difference in scaling? Two identical overhead passes…

Many thanks for the picture comparing both antennas.

There is a small difference, I think you are comparing a non-LNA system with your LNA system.

But apart from that, is clear. I’ve always noticed that QFH is working fine above 18 degrees. I’m thinking on experiment with another tall-width relations to improve performance on lower passes…

You eggbeater is from Anjo Antennen?

73’s de EA5WA Juan Carlos

I’m still surprised how you all can get so good results with omni antennas for UHF. You must have a very noice free RF environment and QTH with free sky.

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I’m convinced that the most important part of the satnogs station is the location.
I’m not free of QRM but I have free sky

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Yes, we have the ANJo Eggbeaters for both UHF and VHF and in parallel a separate TA-1 for APT…

Indeed, we have good LNA 's on all antennas, but even so the Eggbeater gives very good coverage. The TA-1 goes down to 0° Elevation, but picks-up more noise etc sometime…
We are now testing a cavity filter on the APT for 137 MHz…
We also had extremly QRM from 70cm Repeater only 100m away, but it’s turned off now :wink:

The location is at our 20m dish in Bochum, so it is supposed to be a little bit more quiet and has very good open sky coverage…

You can compare some observations here: https://network.satnogs.org/users/dk0sb/

73 de Peter

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