RHCP...

It is and I share your concerns. Any ideas to mitigate.. paint?

DH2VA : do you have a S11-plot (say 2300 - 2500 MHz) of that helix? (or better ... wider span ; -)

Quote from DH2VA

It is and I share your concerns. Any ideas to mitigate.. paint?

Paint might work, or perhaps better make the helix out of copper or brass and solder it to the connector. I have made helices out of either thick copper wire or even 141 semirigid. You can bend copper wire around the N type connector centre pin and make a solid solder joint.

73 Charlie

here the pictures inside my solution for 2,4ghz and 10GHz feed..

I used simple 9cm HT waste pipe material 3 pcs for the housing and a 40mm pipe for the helix .

Picture 1: Housing LNB and Helix reflektor..

Picture 2:

Then adding a piece of plastic to fix the helix pipe..

Pictue 3:

Then adding the original dielectric feed:

Picture 4:

Then putting the helix inside:

The final design fitted on the dish:

There is no influence seeing on 10 GHz when I transmit on 2,4 GHz but my test only with the 500mW from BU-500 at the moment. My Andrew PA is under constuction.

DD0KP : Can you make a more detailed picture of the dielectric lens and/or measure the dimensions?

PA3FYM It is the original lens which is on the ventron exl-t lnb. You could use a simple hacksaw to get it off the lnb. Then with an angle grinder I put the lnb pipe that there is no flange any more. After assembly I put the original lens back again.

New picture with better quality

Thanks Heiner! I have a similar lens from another LNB but that one consists of two parts, sliding in each other. I think this is called a 'Luneberg lens'. Is this the case with your lens too?

Edit: no it's not a Luneberg lens (just googled on it ; -)

PA3FYM Yes two parts fitting together..

DD0KP : Thanks for the information !