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


View this topic in a long page with up to 500 replies per page Create new topic
1 | 2 | 3 
Brunzy
2016 posts

Uber Geek

Trusted

  #2358642 21-Nov-2019 13:29
Send private message

Are there no BER figures?



tripper1000
1609 posts

Uber Geek


  #2358675 21-Nov-2019 13:55
Send private message

An amp behind the TV is unlikely to help you much.

 

Long story short, an amp can't make the signal "better" at the amps output that is was at the amps input, but it can only beef the signal up to overcome down stream losses.(a good one can remove interference such as LTE). 

 

The purpose of amps is commonly miss-understood. Amps are not intended to restore a bad signal as you seem to be needing to do. If putting an amp right behind your TV fixed all problems, they'd simply build an amp into all TV's.

 

Splitters and long coax lengths reduce the signal strength (and Quality). An amp behind the TV can not restore information which has been lost up-stream of it. Once the data is gone, it is gone. By removing some of the extra/bad connections you have reduced up stream losses, retaining more of the signal/info, which is what has improved the picture.

 

The purpose of an amp is to preserve quality, not repair a bad signal. They boost the size of the signal at the antenna so that after the signal has been halved and halved again from running through all the splitters, cables and dodgy connections, the signal that arrives at the TV is hopefully the same strength and quality that left the antenna.

 

Amps also boost the noise, so in all professional installations amps are located at the antenna (or very near to it) because this is where the signal to noise ratio is at it's best. Down at the TV the signal to noise ratio will be at it's worst, so there's usually no point amplifying the signal there. In the TV diagnostics menus, signal to noise is most closely related to the Quality/BER figure and not the Strength. Quality/BER is the most important of the two readings.

 

Another point to keep in mind is that the antenna could be bad or miss aligned. Domestic antenna's are made cheaply and don't last forever. They commonly have very poor weather proofing and corrosion resistance, but people simply don't want to fork our the cash for decent antennas (made of stainless etc). If the design was particularly poor and the installation careless their failure is faster.


ADKM

860 posts

Ultimate Geek


  #2358684 21-Nov-2019 14:14
Send private message

There's no mention of "BER" in the Sony Diagnostics screen.

 

I get what has been said about amplifiers. Although I'm hoping to increase a poor signal, compensating for losses in the splitters may well be enough as removing them shows a marked improvement. I guess trying out one of these gadgets from JC is the best bet. If no improvement I can return it. There's a great signal on Maori TV and a rotten one on 3. Is this my aerials fault, or are the transmissions at a different strength ?




tripper1000
1609 posts

Uber Geek


  #2358691 21-Nov-2019 14:43
Send private message

IME the antenna's fail most frequently because they are subject to the harshest conditions but we have evidence that seems to point to your system needing a mast-head amp and that amp to be faulty (ie the power supply that makes no difference).

 

The channels are generally transmitted at the same strength but I'm not familiar with your area. Differences in reception are most commonly because the different frequencies bounce differently and the reflections can cause stronger and weaker final signal at the antenna/receiver location. Someone down the road could have exact opposite symptoms. When the signals are weak overall, some channels may be just above the threshold required for a good solid picture and some might be just below. Digital does a good job of making a flawless picture out of a weak signal, so your "great" channels might only just barely be good enough and not necessarily a good strong signal. Any component in the system (antenna, coax, splitter, connectors, bad mast head amp) can be the culprit in theory.

 

An amp behind the TV won't give the same results as the same amp at the antenna.


Brunzy
2016 posts

Uber Geek

Trusted

  #2358694 21-Nov-2019 14:50
Send private message

I’d say buying some sort of amplified splitter would be a total waste of time.

A poor signal on one mux and good on another is often indicative of a poor reception area with hills ,trees etc in the way ,but moisture in the cable and some cheap hardware i.e. splitters etc can also be detrimental.
Also the fact you said your analog signal was very poor suggests you may in fact need a mast head amplifier ,but before going down that route first make sure all of the cables are good quality, RG6, and if you can remove any hardware in between i.e. splitters etc and try and have a direct line to the TV and report back on the quality figures then.
If cables connectors etc are all good quality then I’d suggest you get someone in ,as about the only other thing that can improve the difference between muxes is aerial placement ,and to put it in the optimum position you need a spectrum analyser.

ADKM

860 posts

Ultimate Geek


  #2358707 21-Nov-2019 15:07
Send private message

Thanks to all for feedback and advice. I'll ponder what to do next and probably get someone in. Will flag the amp idea.

 

It may be "good enough" now that the extreme pixelation seems to be gone. Will give it a few days.  I can't remove all splitters, as the first in line  is not accessible.

 

Thanks again, Cheers.

 

 

 

 


richms
28060 posts

Uber Geek

Trusted
Lifetime subscriber

  #2358783 21-Nov-2019 16:26
Send private message

Poor on one and good on another is also a symptom of a bad join etc causing reflections in the cables, and also cross modulation from a crap amp being overloaded by LTE or other nearby stuff.

 

If the first splitter isnt accessible you have no way to know if its even terminated correctly so work on getting access to it, or running another cable around where it is located. Also give whoever made it inaccessible the bash if you know who they are.





Richard rich.ms

 
 
 
 

Trade NZ and US shares and funds with Hatch (affiliate link).
ADKM

860 posts

Ultimate Geek


  #2358806 21-Nov-2019 17:41
Send private message

Would it be worthwhile to change the mast head amp?  I can see there is one, a grey box about 3/4 down the hockey stick.
I have checked the Kingray power injector and it's just over 18v off load. But certainly it does not improve the signal when connected.  I assume it should ?

 

 


Brunzy
2016 posts

Uber Geek

Trusted

  #2359075 22-Nov-2019 08:00
Send private message

Yes it should make a definite improvement, but the issue is as I mentioned earlier when you remove the power supply you get no signal at all , so somethings not right ,
I would definitely check it and see.
Is all the cable RG6 ?
And also why is the splitter inaccessible?

1 | 2 | 3 
View this topic in a long page with up to 500 replies per page Create new topic





News and reviews »

Logitech G522 Gaming Headset Review
Posted 18-Jun-2025 17:00


Māori Artists Launch Design Collection with Cricut ahead of Matariki Day
Posted 15-Jun-2025 11:19


LG Launches Upgraded webOS Hub With Advanced AI
Posted 15-Jun-2025 11:13


One NZ Satellite IoT goes live for customers
Posted 15-Jun-2025 11:10


Bolt Launches in New Zealand
Posted 11-Jun-2025 00:00


Suunto Run Review
Posted 10-Jun-2025 10:44


Freeview Satellite TV Brings HD Viewing to More New Zealanders
Posted 5-Jun-2025 11:50


HP OmniBook Ultra Flip 14-inch Review
Posted 3-Jun-2025 14:40


Flip Phones Are Back as HMD Reimagines an Iconic Style
Posted 30-May-2025 17:06


Hundreds of School Students Receive Laptops Through Spark Partnership With Quadrent's Green Lease
Posted 30-May-2025 16:57


AI Report Reveals Trust Is Key to Unlocking Its Potential in Aotearoa
Posted 30-May-2025 16:55


Galaxy Tab S10 FE Series Brings Intelligent Experiences to the Forefront with Premium, Versatile Design
Posted 30-May-2025 16:14


New OPPO Watch X2 Launches in New Zealand
Posted 29-May-2025 16:08


Synology Premiers a New Lineup of Advanced Data Management Solutions
Posted 29-May-2025 16:04


Dyson Launches Its Slimmest Vaccum Cleaner PencilVac
Posted 29-May-2025 15:50









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.