How do I choose amplifier?

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hungugu

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#62635 11-Jun-2010 01:43

With my TV's built-in receiver, Prime/Maori channels are good; TV1 channels are ok and TV3 channels are well below acceptable quality. I would like to get good TV1/TV3 reception so I have try my friend's amplifier today and it worked great!! It was a Kingray 2-way amplifier like this one: http://www.dse.co.nz/dse.shop/4c10eb20034c9e50273fc0a87f3b0691/Product/View/L4219

However I found that the signal gain is only 16db....

There are two other models on the DSE website:

http://www.dse.co.nz/dse.shop/4c10eb20034c9e50273fc0a87f3b0691/Product/View/L2105 with an adjustable knob and 26db UHF gain.

and this masterhead one with 32db UHF gain
http://www.dse.co.nz/dse.shop/4c10eb20034c9e50273fc0a87f3b0691/Product/View/L0040

How do I choose among these three? Is it possible for the signal to be too strong? Is the adjustable signal gain important? Would you recommend any other amplifiers from somewher else?

Thanks heaps in advance!!

Brunzy

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#340590 11-Jun-2010 12:18

You would be better served by fixing/optimising your antenna first,
when it eventually falls below threshold , and you have it repaired
you will probably have an amp that is of no use to you

rscole86

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#340609 11-Jun-2010 13:03

I assume you have analogue TV? As you mention that "below acceptable quality" if you have digital, then its either there, or its not.

This particular forum is for Freeview only, but that does not appear to be what you are using. Where do you live, as brunzy pointed out, you are possibly better off fixing your antenna.

hungugu

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#340633 11-Jun-2010 14:28

I am sure it's a digital tv (freeview HD) and as I said I can get perfect pictures with that amplifier....my problem now is that I am a bit confused by these different amplifiers....

Put it another way, without the amplifier, I got signal quality 0-1 / 10 and signal strength 1-3 /10 for TV3 (I get the mosaic-like picture every 3 or 5 seconds). But now with the amplifier I have 9/10 and 10/10.

I have no idea how to fix / optimise the atenna....for me adding an amplifier is the probably the easiest solution@_@

oxnsox

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#340637 11-Jun-2010 14:50

The problem you describe is indicative of an analogue, not a digital (Freeview) signal. If you were using a Freeview signal then you would have a good picture on all channels as they all come from the same source and are in a similar frequency range for your aerial.

But first it helps if we know what area you live in. You may probably have to alter the direction you UHF antenna is pointed, to improve the Freeview signal quality.

Jaxson

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#340640 11-Jun-2010 15:00

oxnsox: The problem you describe is indicative of an analogue, not a digital (Freeview) signal.

No it's not. "I get the mosaic-like picture every 3 or 5 seconds" definitely sounds like digital.

What is being said here though is correct, you want to try and get your aerial's reception as good as you can first, before you try and make the signal louder. The problem is that an amplifier will turn a bad signal into louder bad signal, so down the line you may have problems as your aerial's quality fails even more.

The above is why it's best to use a masthead amp too, so you take the raw signal as soon as possible and make it louder, rather than allowing that small signal to be distorted as it travels down your cable/joins/splitters etc and then trying to make that louder right before your TV.

Yes, you can have too much signal. That's where the variable amplifiers come into their own as you can dial up just the right amount for your application.

The correct approach as such is to do a check on your whole aerial system. eg is it a proper UHF aerial, does it run directly to your TV via good quality and good condition RG6 cable and does it have good quality plugs on the ends of it? If you have no other analogue TV's then you can do away with VHF aerials and diplexors etc altogether too. Is it large enough for the task and does it point in the right direction?

That said though, you can just work with whatever is easiest and comfortable for you. Dick Smith is famous for it's returns policy so you could just try a few until you are happy too.

robjg63

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#340641 11-Jun-2010 15:01

Err - he(I presume) did say it went mosiac - that does sound quite a lot like a digital picture rather than analogue.

The TVNZ signals are all transmitted on the same frequency, TV3 (tv4 tv3+1 c42) all go out on another frequency (from the same tower but probably a different aerial I would guess), then there are Maori tv chinese tv that are on another. So there are 3 frequencies used. Its possible to get good TVNZ picture and maybe the others bad (or the other way around) if your aerial is not good or something else is interfering. Maybe bad cabling as well?

Which city are you in?
Can you see the transmitter from your antenna? (If so you dont need a booster).

Are you sure your TV has picked up the right transmitter? Try a manual tune (look here for the frequencies you need) http://www.freeviewshop.co.nz/digital-terrestrial-i-8.html

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler