Having read the thread about Outernet migrating to Ku band, there seemed to be some anxiety and misinformation about dishes and LNB’s
so here are my thoughts based on 25 years of TVRO in Europe, its not Outernet specific but its applicable.
Dishes are easy, small dishes are really easy and cheap.
If its bent, rusty etc don’t waste your time buy a new one, although you
can repaint dishes.
Anything under 1m is a small dish. Because of their size they do not need to be pointed accurately. Just mounted firmly so they don’t move with the wind.
Forget the first generation huge C band dishes, modern KU band dishes are manageable. Forget prime focus dishes, offset dishes are easier to mount and being at a steeper angle collect less snow and bird droppings.
Go to www.dishpointer.com and print a map for your loation - it works
For outernet you need to align the dish to a satellite which has lots of transponders on it so its not a matter of finding that one weak signal source there are plenty of signals.
The cheap ones are not much use. I bought one to end to people who ask to borrow my expensive meter because I’m not lending that. I see mention of the Freesat V8 - I bought one recently and its a very good unit and it works.
Its handheld HD television and satellite receiver. Its inexpensive and you can use it to align dishes. It beats sitting in the sun on a hot roof with a small television in a cardboard box.
The first time you align a dish it takes ages. It gets easier. With a map from dishpointer and a meter its easy.
The LNB is a technical marvel and over the years they have got better and cheaper, but they are sold on the basis of hype and the ‘noise figure’ – in practice anything under 0.6db is good.
The common type in Europe is the Astra Univeral LNB which may come as a single output or as a twin, quad, or octo output, with each output capable of driving one receiver. Its common for neighbours to share a dish this way.
The LNB output(s) are in one of a number of states depending on the phantom power from the satellite receiver.
Vertical polarisation 13v
Horizontal polarisation 18v
European LNB’s also double this with the application of a 22Khz tone
No 22Khz tone = Low band (H or V)
+22Khz tone = High band (H or V)
Look on Wikipdia for more information as the USA is different
For larger communal installations there is the QUATRO LNB not to be confused with the quad LNB, this is powered by one voltage and outputs the four signals on separate outputs which is the processed by am electronic switch allowing scalability past the eight receivers an octo LNB supports
Its also handy if the receiver does not provide signalling.
Modest cable runs not an issue with LNB’s as they are designed with a high output, indeed often better results are achieved with the loss in a downlead as the internally amplified output of the LNB may be too high for the receiver.
Satellite uses 75ohm cable. The best sort has a solid dielectric so it does not become a water pipe or get squashed. Buy the proper co-ax for the job. TV antenna cable does work, but is not as good.
Good quality screw on F connectors the correct size for your cable should be used or crimp ones if you have the correct tool for them. Take care none of the braid wraps around the centre connector and shorts it out.
Get some self-amalgamating PVC tape, stretch it and apply over your F connector then it lasts for years. Block up any ports not used on a multi output LNB leave the tape off for just one night and the rain can get in your plug or LNB and wreck it.
Affix the downlead so it does not move around. White cable ties degrade quickly with UV the black ones last longer.
Remember with Ku Band you don’t need to have any other electronics outside.