Hi guys I'm trying to get an invacom LNB which now seems to be out of production and I'm not able to find it so then I was thinking to adapt an Offset Circurlar LNB to a Prime Focus Dish.
how to convert / adapt a circular LNB for a Prime Focus dish?
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Not an easy modification, unless you're a machinist, and have the tools and equipment along with the understanding of what needs modifying and how to incorporate them without introducing excess RF loss... Better off putting it, the circular DSS LNBF, on an offset dish and be 'done with it'. That's probably also a lot cheaper, in material cost alone, than what the modifications require.
For Ku FTA* on a BUD I'd consider the GeosatPro SL1P (*linear polarity, 11.7 to 12.2)
For Ku FTA* on a BUD I'd consider the GeosatPro SL1P (*linear polarity, 11.7 to 12.2)
I already have universal Prime Focus LNBs but I didn't have good reception so I was thinking to use a Circular LNB instead to test if I got better results than those Linear Universal Prime Focus LNBs
Those are all circular polarity, so yeah a circular polarity LNBF would work better than a linear type.
Could try mate it to an ADF-120 feedhorn by cutting off the integral scalar. But think it would be a lot less $$, and easier to 'make work' by mounting on a 1 to 1.2 meter offset dish. Just MHO. Could mount 2 LNBF's on a dish, one dish for 61.5 and 77 and another for 110-119.
Think if you 'get it perfect' in mating said LNBF to the feedhorn, you're going to have comparable performance with the offset dishes. That is, unless you're using a commercial Ku rated prime focus. And the 'aim' will be critical because of the narrow beamwidth of a BUD at Ku.
Have you tried a dielectric plate in the universal LNBF's throat?? Think a piece of a plastic credit card will work [seems I read that a very long time ago]
Found this scroll down to Digital DBS / KU/ C-Band Feed - and This DIY
Could try mate it to an ADF-120 feedhorn by cutting off the integral scalar. But think it would be a lot less $$, and easier to 'make work' by mounting on a 1 to 1.2 meter offset dish. Just MHO. Could mount 2 LNBF's on a dish, one dish for 61.5 and 77 and another for 110-119.
Think if you 'get it perfect' in mating said LNBF to the feedhorn, you're going to have comparable performance with the offset dishes. That is, unless you're using a commercial Ku rated prime focus. And the 'aim' will be critical because of the narrow beamwidth of a BUD at Ku.
Have you tried a dielectric plate in the universal LNBF's throat?? Think a piece of a plastic credit card will work [seems I read that a very long time ago]
Found this scroll down to Digital DBS / KU/ C-Band Feed - and This DIY
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a dialectric plate? how does it works or how can it be done?
About the satellites I first tried 61.0 and 125W with the linear LNBs but I didn't get any better signals so now I want to test my BUD with circular on 61.5, 110 etc.
Wow thanks for the links, the first one correct me if I'm wrong but the LNB you are talking about is the one that says
Prime Focus Digital Feed
PFDBS - $169.99
right?
Then on the second link that's what I was looking for, but I still have to figure out how to sold or a little bit more detail about which internal scalar ring are they using and how to add the pipe to the LNB.
But thanks again.
About the satellites I first tried 61.0 and 125W with the linear LNBs but I didn't get any better signals so now I want to test my BUD with circular on 61.5, 110 etc.
Wow thanks for the links, the first one correct me if I'm wrong but the LNB you are talking about is the one that says
Prime Focus Digital Feed
PFDBS - $169.99
right?
Then on the second link that's what I was looking for, but I still have to figure out how to sold or a little bit more detail about which internal scalar ring are they using and how to add the pipe to the LNB.
But thanks again.
That would be the one.
#2 - There's where it would be an advantage to be part RF engineer & machinist.
IMHO- the tubes I.D. would have to match the I.D. of the LNBF's throat, and somehow be 'glued' together.
The scalar is nothing more than 1/4 wave 'troughs' . 1/4 wave deep and wide. Have a machinist make one out of a block of aluminum?? (provide some accurate drawings as they probably will CNC it) Have some photos for an 'eye's on'?? Drill and tap the backside for mounting??
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