VSAT installation in Democratic Republic of Congo

Satellite Internet Forum.

Welcome, Guest.
Welcome to this satellite broadband discussion forum. Wherever you are and whatever your problem we are here to help each other. Connecting to the internet via satellite is not always easy but is critically important to those in remote places or with poor terrestrial infrastructure. Service providers and customers are encouraged to contribute. Register at the bottom of the forum home page if you wish to contribute or ask a question. VSAT service providers and satellite equipment sellers may feature their products free of charge; just register and get posting. Paid-for adverts, top left and top right, on all forum pages, are also available. Read the Forum rules.

Home Login Register

Satellite Internet forum › General and other topics › Long C-Band feed

Pages: 1

Send Topic | Print

Long C-Band feed

(Read 2775 times)

Ex Member

Ex Member
★★

Apr 13^th, 2012 at 12:11pm

I'm looking for a long throat feed for a 4.5M Prime focus C-Band dish, Receive only, it must be linear dual feed (x2 lnb's) and be longer than the Chaparral dual feeds...this is because of the congestion at the feed (support arms) support won't allow the standard 8" Chaparral with 2 norsat LNB's to rotate or acheive a closer f/d...my question to anybody out there is there a model which can be extended in length or a longer than standard feed?
The proprietry feed that comes with the setup is very expensive and unfortunately not a viable answer to the problem.
This instance arose because we changed over from circ to linear and no-go to alter the original feed.

IP Logged

Eric Johnston

Senior Member
★★★
Offline

Posts: 2109

Reply #1 - Apr 13^th, 2012 at 3:10pm

My first thought was "just remove the polariser or set the polariser at 90 deg instead of 45 deg", but maybe you can't rotate the LNBs gradually to set the linear polarisation adjustment amount.

Has anyone ever merged two L band signals via a 4 port coupler/hybrid to see if it is possible to extract linear two polarisations if the lengths of the input cables are adjusted carefully ? Do you need external reference PLL LNBs with the same external reference 10 MHz supply ?

Best regards, Eric.

« Last Edit: Jul 29^th, 2020 at 1:10pm by Admin1 »

IP Logged

Ex Member

Ex Member
★★

Reply #2 - Apr 14^th, 2012 at 4:27pm

The original polariser is encased, and yes unable to rotate the feed when the pll lnb's are attached...there's just not enough feed tube to move vertically for clearance then rotate for xpol.
I thought there might be some Russian model with this extra length in the feed tube, or some add-on by Prodelin. We actually tried to join two chaparral feeds together, the cable-end being the dual feed and a sawn-off single for the incoming wave but it's attenuating too much (as a back-yard solution)...so yes it's working but not well.
Theres a dedicated tanberg receiver for each port back at the head so we are unable to simply switch it with a dual port lnb.

IP Logged

Pages: 1

Send Topic | Print

Disclaimer, Terms of Use and Privacy Forum User Agreement Forum rules Cookie policy.