Antenna Measurement Confirmation from 0 center

Would like someone to concur please.

800 mhz = 15.9512cm (6.28 inches).

Can anyone confirm I have this right? Thanks in advance

For 800 MHz your array radius could be anything from 6.38 cm to 15.95 cm. But you should have a preference towards sizes closer to 15.95cm as those will give better accuracy.

Are you using the antenna array excel sheet calculator?

UPDATE: Apologies I had the wrong sizing written here, corrected now.

Yes, but very possible inputting something wrong.

Freq to array radius

Acceptable freq range for fixed array.
15.95 cm

Does that sound right?

Confirming yes, a radius of 15.95 cm is fine for 800 MHz.

Thanks, planning on making a permanent fixture to plop on roof for quick deployment.

But is it 800 MHz exactly that you are interested in? Or some range around 800 MHz?

Here’s what I used:
800 antenna
They’re mounted on a pair of pie tins with magnets on the base. The spacing was a compromise to cover 800-1700mhz when I though wx balloons were on 1690mhz. My 5-channel electronic antenna switch is built and bench tested, but not packaged yet.

That smaller array will be significantly blocking the larger one. If the array gets blocked like that it’s not going to work well at all.

I just asked about the band of interested, because if you set the array radius to 16.95cm, 800 MHz will be the MAXIMUM frequency that you can use. The usable frequency range will be roughly 320 - 800 MHz.

I will be mainly looking into 700-875mhz with 750-850 80% of time.

Yes, I ordered those antennas with some grommets and cable management sleeves. But I got larger pizza pans instead of pie. Needed bigger radius.

If you want to cover up to 875 MHz max, then you have to design your array for 875 MHz. So that would be a max radius of about 14.58 cm.

If you design your array for 800 MHz, and then DF a 875 MHz signal you’re going to have problems.

855 is max and 775 is basically the beginning so tried to get in middle

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