Geekzone: technology news, blogs, forums
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.

80 posts

Master Geek
+1 received by user: 2

Topic # 87940 10-Aug-2011 23:31
Send private message

I've seen a local provider selling feedhorns for getting Intelsat 5 C-band on a 90cm dish, i.e a bit smaller than normally what you need. I get Intelsat 5 C-band on a 1.2m dish for instance. Is that idea scalable? For instance I am looking at a 2.4m dish, but the EIRPs for Asiasat3S and 5 would suggest I need a 2.7 or 2.9m dish. With a feedhorn and/or maybe an amplifier on the signal anyone like to guess if I could get watchable signals with the 2.4 metre dish? I have line of sight to the sats as I live on a hill.

Create new topic
6666 posts

Uber Geek
+1 received by user: 568


  Reply # 504956 11-Aug-2011 12:55
Send private message

Argh, big post lost.

Guts of it were:

You don't get masthead amplifiers etc with satellite, like you do with Terrestrial transmissions.

Get a good quality LNB.'s.html

80 posts

Master Geek
+1 received by user: 2

  Reply # 504966 11-Aug-2011 13:24
Send private message

Yes Jaxson,
Ok thanks on the amplifier news.
I'd seen your feedhorns on that URL and will adding a feedhorn give me a bit better signal if I was using a 2.4m dish?

546 posts

Ultimate Geek
+1 received by user: 13

  Reply # 505149 11-Aug-2011 19:02


The scalar rings are used on C-band LNB's to optimise them for "offset" dishes. They basically focus the signal reflected off the dish better.

Using a scalar ring on a centre fed (prime focus) dish will not result in performance improvement as they are designed for an offset dish.

If you can buy a large offset dish you can get a signal advantage over the same size centre fed dish because the LNB itself is not in the way of the signal hitting the dish and the LNB will likely face above the horizon instead of at the ground. (on a centre fed dish the lnb faces the ground which is a large source of noise= less signal/noise ratio).

The other reason a 90cm offset works as well as a 1.2 centre fed dish is that single piece offset reflectors are generally more accurately shaped than multi segment dishes.

Hope this made sense...

don't mess with me.... i'm the hd insider....

6666 posts

Uber Geek
+1 received by user: 568


  Reply # 505218 11-Aug-2011 21:14
Send private message

Yeah as above. If it's a prime focus dish then adding anything to increase the area around the lnb actually blocks signal from falling on the dish. Who know though, if it does work it may be compensating for a problem somewhere else.

Using a good sensitive LNB and optimising your setup is really the best way to be going. Someone here might have first hand experience with your size dish and the satellites you are after.

Create new topic

Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:

Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:

Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:

News »

Intel introduces new NUC kits and NUC mini PCs
Posted 16-Aug-2018 11:03

The Warehouse leaps into the AI future with Google
Posted 15-Aug-2018 17:56

Targus set sights on enterprise and consumer growth in New Zealand
Posted 13-Aug-2018 13:47

Huawei to distribute nova 3i in New Zealand
Posted 9-Aug-2018 16:23

Home robot Vector to be available in New Zealand stores
Posted 9-Aug-2018 14:47

Panasonic announces new 2018 OLED TV line up
Posted 7-Aug-2018 16:38

Kordia completes first live 4K TV broadcast
Posted 1-Aug-2018 13:00

Schools get safer and smarter internet with Managed Network Upgrade
Posted 30-Jul-2018 20:01

DNC wants a safer .nz in the coming year
Posted 26-Jul-2018 16:08

Auldhouse becomes an AWS Authorised Training Delivery Partner in New Zealand
Posted 26-Jul-2018 15:55

Rakuten Kobo launches Kobo Clara HD entry level reader
Posted 26-Jul-2018 15:44

Kiwi team reaches semi-finals at the Microsoft Imagine Cup
Posted 26-Jul-2018 15:38

KidsCan App to Help Kiwi Children in Need
Posted 26-Jul-2018 15:32

FUJIFILM announces new high-performance lenses
Posted 24-Jul-2018 14:57

New FUJIFILM XF10 introduces square mode for Instagram sharing
Posted 24-Jul-2018 14:44

Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.

Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.