Question Freeview signal recently got worse to unusable.

opencube

Active Member
Bit of back ground.

I use a Panasonic TH-50PZ80 plasma tv

I have always had an issue with this TV and freeview interference at my current address and my previous one.

We have a Sony AV reciever that is hooked up to all our other bits of kit, Xbox360, Wii, Humax Freeview HD, Raspberry Pi running Kodi.

I purchased the Humax Freeview HD receiver a few years ago to enable us to receive HD channels, but due to the wife's inability to use more than one remote :), we tend to still use the Panasonic's Freeview Tuner mostly with the Receiver turned off and mostly used for when watching movies.


I know there is one point of failure which isn't helping with my issue. The TV is mounted on the wall, and during install as I didn't have a HDMI cable long enough at the time I joined two together with a coupler...I'm guessing this combined with a poorly shielded RF cable sending signal from Humax box to TV isn't helping. These aren't easy to change as the TV is mounted too close to the wall for access.

The coax from the roof aerial is the brown sort that isn't as good as more modern cables, so to try and minimise interference from HDMI cables i joined the brown coax with a better insulated cable where it enters the house using f connectors and coupler.

I combined this change with a Labgear signal booster, this seemed to help a hell of a lot, it also allowed us to pick up many more SD/hd channels on our new bedroom Samsung TV too, so it seemed like a result.

However after a few months things quickly deteriorated again, and I can't find the reason for it.

I initially thought the Labgear booster may of failed, because the both the Panasonic and Samsung TVs were being affected, so I returned it for a like for like replacement. This didn't make any difference and now it's got gradually worse where we can't really use any of the Freeview channels using the Panasonic's internal tuner.

We can still watch a few HD channels on the Humax box and also on the Sammy in the bedroom but they are the worst they have ever been, and we lost all the channels we gained upon installing the new coax and booster box (BBCFour HD, CBeebies HD, More4 HD).

I'm baffled. Unless the replacement booster we got was faulty too...but I can't see that happening.

I am based nr Luton and Dunstable and I believe our nearest transmitter Is Sandy Heath if that helps.

I have noticed over the years that the signal does seem to vary throughout the year, but this is the worst it has been.

Can anyone help?
 

opencube

Active Member
Strange that the issue has affected our new Samsung TV in our bedroom that receives a signal from the same Labgear booster that the Panasonic TV does.
 

Rodders53

Distinguished Member
Aerial? Location, how old, what type / style and how large?

What does it point toward (what can it see on the way to Sandy)? For example, trees coming into leaf can seriously, and variably, reduce the received signal.

Amplifiers should really be a last resort. The COM7 channels lost are only 6dB down on the main multiplexes, but will be the first to go if close to the digital cliff. Humax: what model? What does it's signal level / quality meter show on all of the currently receivable mux frequencies (ideally do the check 'direct connected' to the aerial and repeat with the amplifier in circuit) and provide the results for analysis?

More precise location would help (village/suburb name at least; ideally a postcode of business, shop, church or pub within 100m or so) to allow reception prediction checks, or even a bit of local knowledge.
 

JH4

Well-known Member
Yeh agree with prev. post. Get that aerial checked out. Depending on where you are, it needs the correct one for the band that's transmitted. ( usually not a wideband either, which can make the problem worse, especially if you are band A. ) Needs double screened cable too.
 

opencube

Active Member
The leaves on trees could be a good point here.

We are in a bungalow, but also in a dip off a main road.

We have a tree in front of the house that obviously has come into bloom in recent months that could be a factor.

The aerial that's connected looks like a Freeview digital arial but I can try get a photo to post here along with the extra info you have asked for.

There is an older aerial on our chimney, looks like old pre digital ones to me, probably in a better/higher location than the one we are currently connected to.

I'll get back later with more info
 

Rodders53

Distinguished Member
( usually not a wideband either, which can make the problem worse, especially if you are band A. )
Sandy Heath was group A for analogue but needed group K for Channel 5 (on 39) and then Wideband once DTT started and still is the correct aerial for it.
(Although a group K would be ideal once again after the 600MHz clearance happens, and will then be the new 'wideband aerial' in the UK).
 

jonno73

Active Member
Pretty sure atmospherics have an impact. Certainly did with analogue anyway. Gets worse in summer basically.
 

TJT1

Distinguished Member
The aerial that's connected looks like a Freeview digital arial
There is no such thing. A TV aerial is a TV aerial. So one TV aerial looks pretty much the same regardless of whether it was put up before the digital switchover or after. As Rodders says, one may be a different band or design from the other. But saying it's a Freeview digital aerial is pretty meaningless, so a photo would be better. It could be that you have the wrong band aerial which, unless it's a wide-band, will restrict the reception of some frequencies/channels.
It could also be ingress of water into the coax, or it could be corrosion in the aerial connection box, or it could be... etc.
Strange that the issue has affected our new Samsung TV in our bedroom that receives a signal from the same Labgear booster that the Panasonic TV does.
Why would you think that is strange? Unless you meant 'has not affected'
 

JH4

Well-known Member
To clarify my point above: a wideband aerial is at it's most sensitive at the top of the range of frequencies, so if you are in a band A region which transmits at the lower end of frequencies you will not pull in these channels so effectively, and may get spurious signals from another transmitter at the higher, more sensitive end, which you don't want - if that makes sense. So it's important to have the correct band of aerial for your transmitter. ( Maplin used to sell W/B aerials in my neck of the woods which were totally inappropriate for my band A transmitter on the IOW. ) A local aerial fitter will have this knowledge, of course. As above, double screened aerial cable is also most important, for Freeview.
 

TJT1

Distinguished Member
But if the OP is on the Sandy Heath transmitter, he needs a wide-band aerial (at the moment). BBCB is on CH 21 and ArqA is on CH 52. Bottom and top of the existing TV band. So while your argument may have some merit as to the fact that wide-band aerials seem to be about 6dB higher gain at the top end, it is irrelevant as far as the OP is concerned.
Double screened coax will give higher protection against impulse noise etc., but the OP's problem does not seem to be caused by that, but general low signal strength for whatever reason. Possibly caused by a poor connection somewhere at the aerial or in the down-lead .
It could also be that the aerial is not pointing the right way, having been 'blown off' by high winds.
If the OP cannot check out the antenna and top end of the coax etc. himself, I would suggest 'getting a man in' who knows what he is doing. If the aerial is pretty old, its could be the the connections in the balun box have corroded badly due to the ingress of water over the years which may also have caused degradation of the el cheapo coax.
Having a 'booster' at the bottom of the feeder is not the place to have one, if indeed, an amplifier is necessary at all. It should ideally be at the masthead. But the decision whether to fit one or not should be based on the signal level received by the aerial and taken at (or close to) the aerial or slightly sub-optimally, at the bottom end of a known good length of coax.
As the OP's reception has been getting worse, it is obviously something 'going down' and as it isn't at the 'bottom end' it must be the feeder or the aerial that is causing the problem. (unless it's something silly like an outer braid whisker shorting to the inner in one of the joints)
 

The latest video from AVForums

Are the TCL MiniLED TVs better than OLED? TCL Interview with Marek Maciejewski | AVForums Podcast
Subscribe to our YouTube channel
Support AVForums with Patreon

Top Bottom