Signal Quality Dropped off

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E3xtc

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Topic # 148548 23-Jun-2014 09:38

I am after some opinions/options please. :)

We have had Freeview working fine from the Auckland Waitarua mast for about 3 years now. For the last 2-3 months the signal quality has dropped off a few percent (using the DishTV meter it shows around 50-65%). Strength is still solid sitting around 80-90%.
So I am getting 'no signal' or chopping/pixelation of the stream. Seems to be worse with Choice/Prime/Sonnet. And seems to be worse during the daytime for some strange reason?!? Although that could be just me being subjective - although the stuff we record through the night doesn't seem as badly impacted.

The aerial on the roof is already a large one - with lots of fins/elements/whatever they are called. And we have a masthead amplifier installed. All was installed (in a new build, so cabling/joints/etc should be all good) by a professional/qualified dude.

According to the Freeview coverage map we shouldn't have signal, so we are really batting against the odds in any case - but I really wanted HD rather than the satellite SD stream :) and like I said, it has been working fine for the past 3 years.

So I am thinking that maybe some trees have just grown to the point where they are now blocking more than enough of the signal to knock it out and make it sort of unusable.

Does anyone have any brilliant ideas? Would putting the aerial on a tall mast on the roof buy me another 3 years or so? Any other recommendations/ideas?

Cheers
Troy

turb

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Reply # 1072426 23-Jun-2014 10:34

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I think you should get someone in. Otherwise you'll be chasing your tail/spending money trying to isolate which of those issues (or something else) is causing the problems. And getting stressed every time pixellation comes on the screen!

He'll have the right gear to test all the different bits of your antenna system.

It'll be $100-$200 for the peace of mind that you have everything as good as it can be.

Not a very geeky answer but there you are...

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B1GGLZ

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Reply # 1072480 23-Jun-2014 11:25

Could be due to water ingress and/or corrosion. It's amazing how much salt there is in the Auckland atmosphere which causes massive corrosion with TV antennae.
First thing I'd check is all connections at the antenna and amp and also look for corrosion on the circuit boards. It's probably just slow deterioration of the antenna system due to weather exposure.

richms

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Reply # 1072521 23-Jun-2014 12:04

Some amps don't like cell signals much at all and there may be more people using cellphones where the antenna is aiming then night time.

Richard rich.ms

FOCUS0

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Reply # 1072545 23-Jun-2014 12:53

I also noticed a change after the May Re-stack

I have had a phased array pointing at Waiatarua with Masthead Amp for at least 3-4 years and not had a Problem with my channels.

I sit behind a hill and it was the best way to get HD and was pleased it worked.

After the restack the Signal level seemed to have dropped, and I was getting constant signal loss on Channels.

In the mean time I've simply put an additional in-line amp which has stabilised the situation, however it is not a clean fix.

Will need to get my Aerial setup checked over as there may be an issue with the Masthead AMP and the change in frequencies.

When I checked the signal Levels (without the in-line amp) on my Tele from a channel (1,3,5,16) off each of the 4 muxes there was about 15% variation from the worst to best.

Should all be at the same level.

E3xtc

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Reply # 1072561 23-Jun-2014 13:14

FOCUS0: I also noticed a change after the May Re-stack

....

In the mean time I've simply put an additional in-line amp which has stabilised the situation, however it is not a clean fix.

Will need to get my Aerial setup checked over as there may be an issue with the Masthead AMP and the change in frequencies.
....

That is interesting that it happened around the same time for others too. When you mention 'and issue with the Masthead AMP'...what sort of issue could there be that would have been caused by the re-stack? Or are you just thinking that the AMP might be due to replacement in a general sense?

I tried an in-line amp on the main TV which is most watched; but due to the signal strength being around 90%+ it actually caused more problems than anything.

What did the May Re-Stack actually do that would/could have impacted on the signal quality?

Thanks all for the feedback thus far - so it looks as though I can jump on the roof, eye ball the masthead AMP for corrosion/moisture/etc and if nothing amiss there, just get someone in to take a look...argh....

B1GGLZ

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Reply # 1072610 23-Jun-2014 14:03

E3xtc:

What did the May Re-Stack actually do that would/could have impacted on the signal quality?

The May restack introduce a new mux and shifted those in the higher channels (40+) down into the lower channel area (28 - 40) to free up Radio Spectrum for other use. That's a considerable shift in frequency of about 80 - 100mhz lower. Depending on antenna specs and amp specs/passband and setup it could have had a significant effect on received signals.
Good idea to get on the roof and inspect. A Pro with the proper gear can locate the best spot on the roof for your antenna. Moving just a few feet laterally and/or raising it higher can possibly make a big difference. Could also make it worse of course.
P.S. I think the Prime mux shifted from CH45 down to CH37 on Waiatarua.

E3xtc

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Reply # 1072611 23-Jun-2014 14:05

Thanks all :)

Will find out who we got to take a look at it initially and give them a call for a follow up :)

Cheers