Attaching aluminium window screening to extend perimeter of LRO-H2 Solar Cooker Radio Telescope

[Andrew Thornett]

Today, I have managed to attach the aluminium window screening to the framework I attached yesterday. Lots of cuts on my hands from the edge of the screening - but they'll heal - so, now the question is whether it makes a significant difference by reducing ground noise reaching the feed.

The answer to that will become clear over next couple of days.

Andy

[Marko Cebokli]

Hello Andy!

From the photo it seems that you are using a two mode horn (known as "W2IMU" among HAMs). This already has a rather narrow beam, more suited for shallow or offset dishes (f/d about 0.5...0.6). Your dish (by eyeball measure :-) looks deeper than that, so you probably already have a low edge illumination, hence low spillover noise, so the mesh rim will only reduce it a little bit. Maybe you could switch to the wider beam Koch feed, which will give a better illumination (gain), with the mesh rim keeping its noise pickup low.

Marko Cebokli

08.06.2026 16:03, je 'Andrew Thornett' via Society of Amateur Radio Astronomers napisal

Today, I have managed to attach the aluminium window screening to the framework I attached yesterday. Lots of cuts on my hands from the edge of the screening - but they'll heal - so, now the question is whether it makes a significant difference by reducing ground noise reaching the feed.

The answer to that will become clear over next couple of days.

Andy

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[Andrew Thornett]

Thanks Marko. I am intending to swap out the feed for a scalar horn (cantenna with sort of Mexican hat) but first I need to stabilise the structure as it flexing. Plus Ive got to finish the series of tests currently underway - done by end week.

Andy

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From: sara...@googlegroups.com <sara...@googlegroups.com> on behalf of Marko Cebokli <s57...@hamradio.si>
Sent: Tuesday, 09 June 2026 06:40:44
To: sara...@googlegroups.com <sara...@googlegroups.com>
Subject: Re: [SARA] Attaching aluminium window screening to extend perimeter of LRO-H2 Solar Cooker Radio Telescope

 

To view this discussion visit https://groups.google.com/d/msgid/sara-list/873c532582476dd88982c07a096ba37f%40hamradio.si.