Retrofit advice anyone?

The mission is to upgrade an existing outernet Ku-band setup to L-band on an art sculpture (see previous post here: https://discuss.outernet.is/t/outernet-receiving-station-as-transmission-art-sculpture/2229 )

I’m tossing around ideas for upgrading, here are some options I can think of so far.

One idea is to simply house the CHIP-L-band patch antenna somewhere on the structure (in weatherproof housing) and ignore the existing dish antenna. This would maybe-probably work but seems inelegant.

What about the idea of using the existing 90 cm Ku-band dish with the L-band patch air gap antenna, like this example (halfway down the page, image caption ‘90cm dish with modified GPS patch antenna’) http://jontio.zapto.org/hda1/jaero.html What they are doing seems similar (AERO signals) so could work for outernet (?) though the person admits this isn’t really the best thing to do because of signal polarization but that it kind of works anyway. There are other issues that this path would raise, like where to put the amp-radio-CHIP in relation to the antenna (mount the whole thing on the dish? Get a 10-ft or so extension cable between the amp and the radio—what would this extension cable be exactly and would there be signal loss in extending it? Etc etc.)

And so I wonder about mounting, instead, a homebrew helix antenna in the 90cm dish. This would solve the cable extension issue—I could run an about 10ft coax from the antenna to the radio and CHIP (where would the amp be? Wait, would there be an amp?) which I could house underneath the structure in a suitable weatherproof container. It seems this could work—I’m looking at similar setups, e.g. spongella’s post here https://discuss.outernet.is/t/new-l-band-setup-for-outernet/2418 (smaller 30 cm dish and other differences) and cbander’s setup description here: “ if I use my 8.5 foot C-Band satellite dish with a helical coil and my SDRPlay, I get an SNR of around 20 dB” (from ‘trouble connection, maybe it is just NYC?’ thread in this forum).

Any input would be helpful. I might of course try all of these and see what works best—the issue is that I have limited access to the sculpture so am trying to work out as much as I can ahead of time and do and upgrade install in one or two days.

I was thinking about a dish and RTL dongle only attempt at decoding Outernet.

My thinking was how could very poor people get Outernet. I thought about $7.50 might be enough money.

The answer I came up with was use as many parts that they already have.

At the scrap metal shop here in Asia there are a lot of 60cm to 90cm discarded satellite tv dishes. These possibly could boost the signal say 20db .

If i set one of these up with a helix antenna and fed it straight into a S7.50 blue chinese R820T2 RTL-SDR dongle with no filter or Low noise amplifier. I assume the directionality of the dish should help limit the noise some what and help boost the SNR.

Then a simple Raspberry pi or old laptop with Outernet Library on a Virtualbox share could then decode the data coming down.

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