Dish Feeds

[g0mjw]

This afternoons project was a dual band feed based on DJ7GP design.

Dual_Band_Feed.jpg (829.99 KiB) Viewed 7021 times

I am pleased with the match.

I won't know how well it actually works until I try it of course.

[m0eyt]

Here is my effort.

20181216_173725.jpg (80.77 KiB) Viewed 7015 times

Response is pretty much identical to Mikes.

regards,

Paul EYT.

BTW I have the CAD files for this so its literally a 10 minute job to cut out the reflector / driven element.

[radiogareth]

CAD files, yes please. Any interest in a few blanks, I could arrange some laser or waterjet cut discs.

Gareth

[dh2va]

You are aware, that the plastic cap is not a rain protection but should be a dielectric concentrator?

[g0mjw]

You are aware, that the plastic cap is not a rain protection but should be a dielectric concentrator?

Yes - that's why it's there. I wish there was an easy way to get them without cannibalising a rocket LNB. Apparently some of these rocket LNBs have PLLs but not the ones I have received.

It seems to work - not too badly.

Feed_In_Place.jpg (747.99 KiB) Viewed 6896 times

[radiogareth]

A simple job for 3-D printing assuming we could work out how either PLA, PETG or ABS would behave. Other plastics possible too, like nylon. Happy to CAD and print something to experiment with if it helps.
Gareth, G4XAT

[dh2va]

Yes - that's why it's there. I wish there was an easy way to get them without cannibalising a rocket LNB. Apparently some of these rocket LNBs have PLLs but not the ones I have received.

It seems to work - not too badly.Feed_In_Place.jpg

Just asking.. it looks completely different to the original design by DJ7GP. But he would know the details.

[g0mjw]

How does it look different? It is the same design. He had a different dielectric lens I think but that's all.

Mike

[radiogareth]

A bit of goggling found this article: https://ieeexplore.ieee.org/stamp/stamp ... er=7637125
I understand all the 3-D printer speak and have a printer equal/better than the Replicator 2x mentioned. If someone can work the maths and provide dimensions, I'll happily CAD it and make some.
LMK
Gareth, G4XAT

[dh2va]

Sorry to be unclear:with 'different' I mean 'not identical' . I would assume that shape and material are critical for the resulting beamwidth, just like in optics.
https://www.darc.de/der-club/distrikte/ ... 24-10-ghz/

But comparing its G/T to a standard LNB by checking the Astra 2C beacon (as example) should confirm its performance. It would be certainly one of the nicest designs I have seen and my personal favourite.