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. Both service providers and customers are encouraged to contribute. If you are showing as 'Guest', please register at the bottom of this home page if you wish to contribute or ask question. May 2018: GDPR: Updates to Privacy and Cookies policies: As you may know, a new EU data protection law called GDPR will apply from Friday 25th May 2018. As part of satsig's commitment to protecting the privacy of site visitors and forum members, I have therefore updated the Privacy and Cookie policies. There are now links leading to these policies: Disclaimer, Terms of Use and Privacy, Forum User Agreement, Forum Rules and Cookies at the bottom of the home page and all forum pages. Read the Forum rules.

Satellite Internet forum › Dish pointing and alignment › Modifying Prodelin Series 1250 from C to Ku band

Pages: 1

Send Topic | Print

Modifying Prodelin Series 1250 from C to Ku band

(Read 1044 times)

Admin1

YaBB Administrator

Offline

Personal text from: Profile,
Options, Top line

Posts: 856

Apr 30^th, 2017 at 7:39pm

Put here by forum admin from email..

>>>Modding an old Prodelin Series 1250 from C to Ku, on a remote island...

Have Ku feed assembly but need to position it on the C "platform"...
Question about the focal length: compared to the position of the
existing C horn mouth, where should the Ku window be located? Same? A
bit closer to reflector? Or someone has the "ABCD" dimensions for Ku?
Any estimate highly appreciated!

Thank you

Cheers

Christian

Owner, ICTL
Main Camp, Kiritimati Is.
EASTERN Kiribati
ictl@linnixislands.com
+1 808 441 1939� �-voicemail n fax to/from email
Time Zone: GMT-10 (Hawaii)

================================
Reply:

I think this is the key document that you need to download and print:

http://www.gdsatcom.com/vsat/Technical_Docs/feed_location_drawings/TD0641.pdf

It has ALL the ABCD measurements.

The document shows ABCD dimensions for various feed window diameters; so good for C or Ku band.

The phase centre of the feed should match focal point of the dish.

The phase centre of a feed is known only to the manufacturer. For a conical horn the phase centre may be at the aperture or further down inside.

If you examine the ABCD lengths, it is to be observed that as you reduce the feed diameter the distance the feed window needs to be from the dish increases. This indicates that for the Prodelin feeds the phase centre is deep down inside the conical horn.

Best regards, Eric.

WWW

IP Logged

Pages: 1

Send Topic | Print

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