Lost channels

Boycey18

Novice Member
Hi, ok fitted a new tv and tuned to the Antenna all great .... connect to router all great , this was an extra tv so there’s now 4 in total .
After the sparky left the down stairs channels were jumpy so I got him back and he fitted a booster, now the new tv only tunes to 7 channels starting at no 21 ..... sparky won’t come back and says it needs an antenna guy ...!!! Antenna looks to be new and is in the roof space ..... checked all connections and they look fine any other ideas ...???
 

Rodders53

Distinguished Member
Oh my. Sparky. Wrong trade for the wrong job (although some are good at such stuff).

Photos of what is there now, and what was there before would be ideal. But my 2d-worth and guesswork on your installation:

Three TVs passive split from one aerial (how?):
Two-way splitter... one output to lounge TV -4dB ref the aerial. Good.
Second output to another 2-way splitter to two other bedroom sets -8dB also good.

Use a third 2-way splitter to lounge and 4th bed, from the first splitter output 1, so -8dB to both, is OK in bedroom but not on the more distant lounge? Why? Poor connections or very lossy cable to that TV alone?

4-way Amplifier-Splitter in place of all the passive splitters doesn't help - but none of the other three TVs have a problem = not too much signal out of the amplifier causing overload.

So a connection or cable issue on that lounge TV set. QED.

Prove by connecting aerial direct to that lounge TV cable with a joiner if necessary (or back to the original 2-way splitter)?

Looking good and being good may not be the same thing. Disturbed connectors can simply need a re-make.

Splitters, amps and diplexers - A.T.V. Poles, Brackets, Clamps & Aerials and
Wiring up plugs, aerials and wall plates - A.T.V. Poles, Brackets, Clamps & Aerials are worth reading and will show you how to re-make the plugs?
 

JayCee

Distinguished Member
Always use an aerial company.
In my experience ”Sparkies” are obviously fine for electrics but have a very limited knowledge when it comes to aerials and signal distribution.
 

Rodders53

Distinguished Member
Further thoughts.

If sparky just put a one way booster (amplifier) behind the problem TV set, it won't help if the issue is where the splitters are located. It needs to be between aerial and the first split...
 

Boycey18

Novice Member
Have tried some fault finding ..... took antenna from problem tv and connected direct to the antenna .... re tuned and hey presto all 170 odd channels are there ..... re connected via booster and there now not available....😳 back to only 7 connect to a different connector in booster still problem .... is it a booster and antenna conflicting ..... is this a thing
 

Boycey18

Novice Member
Further thoughts.

If sparky just put a one way booster (amplifier) behind the problem TV set, it won't help if the issue is where the splitters are located. It needs to be between aerial and the first split...
[/QUOTE
If you look at my pic the booster is AFTER a split ..... is that the problem ...? The booster MUST be directly after the antenna
 

Rodders53

Distinguished Member
Location (where you live roughly) will allow estimation of signal levels available in the loft.
Postcode of a nearby shop, church, school etc.,. we don't want your exact address!
 

mikej

Well-known Member
Not sure why there would be a splitter before the distribution amp, as there looks to be more than enough TV outputs. Unless I'm missing something, you need to feed the aerial directly into the amp's UHF input (as Rodders mentioned above) and take outputs to all TVs from the amp's TV outputs.
 

Boycey18

Novice Member
Antenna must go into UHF in not VHF in.

You'll need Belling Lee TV plug to F-plug adapters to do it or re-make cables with F-plugs.

DO NOT use the Full output and it should really have a terminator fitted Splitters, amps and diplexers - A.T.V. Poles, Brackets, Clamps & Aerials
EDIT: Labgear say the same and supply the terminator (user handbook pdf)

Disconnect brown coax and find where it feeds (short the inner to outer)?
Ok thanks heaps, What I’ve done confuses me even more .... while the problem tv was connected to the antenna first I te programmed
I’ve put it all back as it was but while the problem tv was connected to the antenna first I re turned it..... ive left the antenna disconnected as it’s already the second tv since the problems started ( the first lost all power ) did we pop an internal part ...? So now I’ve got all channels... to many to count .... with no antenna connected .....are they coming through the wifi ..... fu$& it it all works 😂
 

Rodders53

Distinguished Member
You can get direct signal pickup via connected cables. Sounds to me like you are in a very strong signal location... Where? (approx).

My bedroom TV works on a stripped back length of coax - not that I'm recommending that as a reliable way to do it.
 

Boycey18

Novice Member
You can get direct signal pickup via connected cables. Sounds to me like you are in a very strong signal location... Where? (approx).

My bedroom TV works on a stripped back length of coax - not that I'm recommending that as a reliable way to do it.
Litton Aston ... Sutton Coldfield .... got everything just the coax in the tv into the loft space .... this seems to have done it Maybe the tower in the pic ... is this a tv mast 😂
 

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Rodders53

Distinguished Member
Certainly is.

Been there quite a few times.

You won't need that amplifier if you are that near.
Passive splitting should work OK for four outlets.

Little Aston Golf Club B74 3AN: Wolfbane gives 106dBuV/m - only a mile away. But that estimator doesn't allow for the deliberate beam aiming over the head and to the horizon of the transmit antennas. So it will be a fair bit lower.

Roof material (loss) say -10dB
Antenna gain say +10dB
4-way splitter loss -8dB
Cable and connection lossed -2db

So overall -10dB on what is outside... say around 96dBuV at each TV. Ideal level at the set is between 45dBuV and 65dBuV.

Add 10dB from the amplifier = guaranteed to overload the amplifier itself and any attached TV tuner which results in the classic 'loss of channels' (TV meters reporting high signal level but poor/varying quality).

It's even likely that you may still be overloading the lounge TV. Sparky may have just re-made a joint/connection that was previously losing enough signal to make it no problem?

An attenuator or a splitter on that feed will reduce it, if required. Get metal shielded ones, rather than plastic bodied. Read up those links I posted!

Do use the TV signal level/quality meter(s) to see if they show anything useful when re-jigging things. BUT don't retune the TVs as that just loses all the tuning data and makes connection fault diagnosis more difficult.
 

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