dielectric plate

[Archive-8]

Hi what material can I use to make a dielectric plate to turn a circular lnb in to pseudo liner?

Eg foil or old credit card ect?

 

[Terryl]

Some have had success with a Teflon cutting board cut to size, but most just buy one for a "C" band LNB.

But some circular LNB's can't be changed over to a linear LNB, this due to the way the internal circular antennas are setup.

 

[Archive-8]

I have a couple of plates for c-band lnb's. I didn't really want to cut them up.

To try modding one of my Ka Band lnb's.

 

[Archived-1]

Hi what material can I use to make a dielectric plate to turn a circular lnb in to pseudo liner?

Eg foil or old credit card ect?

Lots of information here Chris .
https://www.satellites.co.uk/forums/threads/dielectric-plate.115537/

 

[Costactc]

Most, if not all, c band lnbfs come with the dielectrical plate.

 

[BlindFaith]

Hi what material can I use to make a dielectric plate to turn a circular lnb in to pseudo liner?

..isn't that the other way round? ;)

 

[Archive-8]

I am trying to see if I can get h+v from my Ka inverto.

 

[BlindFaith]

if you want to use a circular lnb to receive linear polarisation, you have to remove the dielectric plate ;)

 

[Captain Jack]

I know circular Ku LNBs have a plate in them like a C band LNB does. SL3 Ka LNBs use a different method... Using a 'septum' on the PCB itself. I don't know what's inside the Inverto one. Have you opened it up?

 

[Archive-8]

Not yet I was trying to find out a bit more first. I am going to have to remove the bed cap first.

 

[Trust]

Here the job I made at the Triax TKT 001 , the Inverto will be almost the same .
To have better control while milling the rests of the cutted plate in the throat , I put a PVC plate in the housing .

 

[Archive-8]

Inside the inverto L+R Ka Lnb

 

[Channel Hopper]

if you want to use a circular lnb to receive linear polarisation, you have to remove the dielectric plate ;)

Or use a second dielectric in reverse ;)

 

[PaulR]

Surely using a circular lnb to receive linear polarisation will simply result in a 3dB signal reduction. Or am I missing something?

 

[Archive-8]

View attachment 72277 View attachment 72278 View attachment 72279 View attachment 72280 Inside the inverto L+R Ka Lnb

 

[Archive-8]

Surely using a circular lnb to receive linear polarisation will simply result in a 3dB signal reduction. Or am I missing something?

Can you get a H+V Ka lnb easily in the uk? With feed horn?

 

[PaulR]

Dunno. I was just talking theoretically about circular and linear polarisation.

 

[BlindFaith]

Surely using a circular lnb to receive linear polarisation will simply result in a 3dB signal reduction. Or am I missing something?

yes, cross polarisation ;)

Circular polarisation wth a linear lnc will result in -3dB (both on the horizontal and vertical probe)

 

[PaulR]

You would have to have H and V polarised signals on the same frequency for that though. H and V alternate to increase the differentiation between adjacent frequencies, or so I thought.

 

[Archive-8]

Here the job I made at the Triax TKT 001 , the Inverto will be almost the same .
To have better control while milling the rests of the cutted plate in the throat , I put a PVC plate in the housing .

View attachment 72188View attachment 72189View attachment 72190 View attachment 72192

Do you have to de-solder the circuit board? Or can you get the front plate of to mill it?