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Permalink Reply by James Gray on April 22, 2013 at 23:50

Yes, you'll more than likely want to replace the ribon cable. While it can technically be used for UHF, most UHF antennas these days have their driven element integrated with the balun (which you'd have to remove), and it certainly can't be used for satellite.

You could maybe give Freeview HD a go. The advantages are:

-Better picture (1, 2, and 3 are broadcast in 1080i)
-There is less to go wrong with a UHF antenna than a satellite dish
-Because the receiver is built in to most new TVs, there is one less remote, on less box by your TV, and you don't need to keep replacing boxes as they fail over the years (just the TV)

But that said, My boss's house in the western half of New Plymouth is in a valley surrounded by trees, and we've spent countless hours trying to get a stable picture but had no luck.

You may be able to get the gear you need to try UHF cheaply enough (UHF antennas are cheap enough, receiver may be built in to your TV, and you can use the same cable as the satellite dish), but all bets are off when it comes to trees.

A good quality 60cm dish, aligned correctly, shouldn't have any trouble with rain fade.

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Permalink Reply by James Gray on April 23, 2013 at 0:17

Also, Matchmaster are good to talk to, give them a call on 0800 aerial, they might have a suitable UHF antenna for you

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Permalink Reply by Graham on April 28, 2013 at 9:24

Thanks for your input James. Most welcome. An update: Found that I have line of sight to transmitting mast above Aramoho from one window on one side of the house (no trees in the way) so have put a 11db amplified indoor antenna there and tv goes well in that room on all channels even with 8m of coax cable. Unfortunately that room is not the lounge, so extended 8m cable another 10m to lounge but there I do not get all channels. Wondering if another booster/amplifier in the coax cable somewhere might help, what amount of boost I might need, and what type of booster to try? Having fun :)

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Permalink Reply by James Gray on April 28, 2013 at 9:37

What kind of coax are you using? If you have RG-59, maybe try replacing with some RG-6

http://www.jaycar.co.nz/productView.asp?ID=LT3281&keywords=UHF+... looks like a nice cheap option (the matchmaster and hills indoor distribution amps are around $100 to $200 apiece)... The loss on RG-6 is around 4.5 to 6dB per 100 feet, so 20dB should be plenty

Connect it close to the antenna rather than in the middle of the cable

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Permalink Reply by Graham on April 28, 2013 at 9:53

Thanks for the prompt and helpful reply James. 10m cable says RG6 on it 8m says 3c/2v on it. Will any tv amp be ok that gives 20db? - I think a friend has one he is not using. Could amp be connected close to tv? - can then switch it on when I switch tv on. And is it ok to leave the 11db antenna switched on as well? - don't want to cause damage to anything.

I note that the signal varies as I move the 10m cable about. There are electric leads, phone and ethernet cables near it. This is hard to avoid.

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Permalink Reply by James Gray on April 28, 2013 at 13:45

I'm not sure what 3c/2v means but if the cable is a similar thickness to the RG-6 it is probably the same, if it's thinner, then it's probably RG-59.

Yeah should be fine, but ideally it would be connected close to the antenna as you want to amplify the signal from the antenna, not noise that it's picking up on the way... Your receiver should have an automatic gain control circuit anyway, so the signal to noise ratio is more important than the signal strength that reaches the TV...

You can get an amplifier designed to be mounted on an outdoor masthead, that has a separate power supply (which you connect at the TV end of the coax)

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Permalink Reply by Bill McMurray on April 28, 2013 at 21:39

James Gray said:

I'm not sure what 3c/2v means but if the cable is a similar thickness to the RG-6 it is probably the same, if it's thinner, then it's probably RG-59.

 

Hi James & Graham,

3c/2v cable is one of the very first coaxial cables (about 35 - 40 years old ??) and is definately not suitable for carrying a digital signal. In fact, you could find that most of your signal will dissipate away in an 8 to 10 metre length of it, because it doesn't have any "low loss" capabilities at all, and the inner core is braided, so it's very difficult to fit F connectors to it -(which you must use for digital!). - Chuck it out!

2002 cable came out after 3c/2v, then 2006 cable came out in the 1980s, and then RG59, which we started using in 1990 for the Sky UHF installations! RG6 cable came out when Sky started their satellite installations about 17 - 18 years ago.

Cheers Bill.

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Permalink Reply by James Gray on April 28, 2013 at 22:01

Thanks Bill, very interesting information... My background is telecommunications and IT, and picking up a few things about satellite/antenna installation, and I've been working for just over 5 years, so I guess that would be a bit before my time :)

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Permalink Reply by Graham on April 29, 2013 at 7:42

Thank you for that information Bill. Will get a new cable and see what happens. Also thanks for your further information James.

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Permalink Reply by Graham on April 29, 2013 at 8:05

Any tips on what type of coax I need with phone, power and ethernet cables nearby? Dual shielded? Quad shielded? Something else?

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Permalink Reply by James Gray on April 29, 2013 at 13:23

I've never run in to any issues with cross talk, just with dual shield RG-6, so long as you're reasonably sensible with cables run long distance in parallel... I wouldn't expect it to be any issue over the distance you're looking at, so long as you aren't trying to make some kind of combo antenna/AC lead (and why would you?)

Remember if you're installing cable in to the walls or crawl spaces, you must have 50mm or a physical barrier between any ELV services (phone, ethernet, TV coax, etc) and any power cable.

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