From time to time people find that their Freeview box, integrated set (idTV) or Personal Video Recorder (PVR) has lost many channels without any apparent changes.
There are a number of factors to consider
Freeview is broadcast on digital multiplexes. This means that, once broken down into a stream of bits, each television channel is combined into a single transmission of 1s and 0s. This means that reception is of the multiplex first if this is lost it affects all the channels in the multiplex in the same way.
The signal strength received by the box or TV for a particular multiplex from a given transmitter determines if the data can be received or not. So, a poor signal results in no data, an adequate signal in perfect data and a low signal in either none or all.
Poor digital signal levels do not result, as they do with old-fashioned analogue television, in a sub-standard picture or sound. Poor signals often result in a perfect data-stream, but are prone to periods of no reception. Sometimes this will be for hours, but can also be several times a minute when caused by induction from fridges, freezers, central heating systems, two-stroke scooters, baby monitors and so on.
The RF connectors need to be in very good condition to work. There are two general types:
Factory-fitted connectors are very reliable as they cannot easily be taken apart, but they can be damaged by wear and tear. On the female-type the central section is often composed of two parts which can often be forced apart, resulting in a poor connection you can push them back together if this has happened with a pair of tweezers. On male connectors if the central pin is damaged, you will need a new cable. If there are any loose partials in the connector, remove them.
Another problem with these cables is that quite easy to sprain the connector at the back which causes little obvious external damage, but disconnects the internal connection. This happens often when a set-top box is pushed backwards into a cabinet.
Hand made cables can also suffer from similar problems to factory made ones and they are also prone to accidental damage from a cable being pulled. If such a connector is not firmly attached to the cable, the connector may need refitting.
Make a visual check of the cables. There are a few basic checks:
If the cable has been slashed or cut, it will not be very effective or reliable. If such a cable is fitted externally, this can allow rainwater to enter the cable and this will reduce the signal levels.
You can easily damage an RF cable by crushing it, for example in a door. If the outside of the cable has a permanent kink in the cable or has been very tightly looped, this could be the site of damage.
For reliable and effective Freeview reception, a rooftop aerial is required. It is hard to make a visual check of such an aerial without putting yourself in potential danger.
You can make a visual check of the route between the aerial and the transmitter. Any form of obstruction will damage the digital signals. In particular trees coming into leaf, as these will leech the signal before it reaches your aerial. This applies to both trees adjacent to the aerial and at a distance.
Another common problem in cities is building work. A large crane will often change position many times during the day, and if this is between your aerial and the transmitter this can reduce the signal levels in an unpredictable way.
If your system uses a booster, the power may have failed. Check the fuse to the power to the booster.
There are two main weather problems that effect Freeview reception.
philip Barrett: I just checked the spec on the web. Now I've always liked the 5 series, and the ones we've sold for the past couple of years have had an HD tuner as standard. Argos are knocked them out at 329, and if you'd bought one at that price, then I'd certainly expect it to have HD (and be smart). However, if you bought it from the likes of Pixamania, then the price of 199 (and just 2 HDMI's) means that its unlikely.
The LG site does not mention whether the tuner is DVB-T (freeview) or T2 (HD), but since the description is 'with Freeview', I'm afraid your not getting HD channels becuase it has no HD tuner. If you paid 300 notes, then take it back, because you've been ripped off (there is a reason I'd never buy a TV from catalogue shop or supermarket), and get your money back. We are knocking out the perfectly decent 580 model (so Freeview HD and Smart) for 329 Buy LG 32LF580V LED HD 1080p Smart TV, 32" with Freeview HD and Built-In Wi-Fi | John Lewis and the 650 series (so 3D as well, and a slightly better contrast ratio) for 369. Or the decent Samsung J5500 (again, Freeview HD and Smart) for 299.
I feel sorry for you - this sort of question had started to die off, with decent brand TV's generally now having Freeview HD tuners as standard, but obviously there is still a market - I just wish retailers would make it clear.
If you paid less than 200 notes for it, you can't expect that much. I've just got (as a hand me down) pretty much the same thing, but when LG were still doing LCD. With only 2 HDMI's iys a bit difficult to upgrade, but I've just bought a Manhatten T2 reciever for 44 quid. Not just an HD tuner, but also does Iplayer (if plugged into ethernet). A bit twitchy with signal strength on HD (a bit sensitive), but decent so far.
MikeB /philip Barrett: The manual I have for that model indicates that HD tuners are only fitted in the Satellite version, non Satellite types being fitted with a standard DVB-T tuner.
On checking around a few suppliers of this model, I failed to find any of the outlets advertising it as being capable of receiving HD transmissions, a couple of examples seen on the undermentioned link.
jb38: LG tend not to even mention the sat tuner, but its nice to have it, all the same! Its really annoying that people are still buying TV's with just Freeview in them, but expecting more, because of the big letters HD used in the blurb by the likes of Argos. I know its all about price, but a clear description of the limitations of the set would be helpful. Once agin, its wise to read the small print, and remember that cheap is not cheap, expensive is not expensive.
I have freeview in my Televison Panasonic TX-L32G10B, also in my Panasonic DVD Recorder DMR-BWT700, I can get Channel 81 Talking Pictures on my DVD Recorder but not on my TV.
I have tuned in the TV, both manually and auto, but still " Invalid Channel" show's up.
I have looked in the guide and there is no channels in the 80's.
Anyone got any suggestions
William Floyd: The manual for this model indicates that HD reception is only possible when on Freesatmode, not Freeview. A way to verify if this is correct or not being to have a look at the EPG listings, if 101, (BBC1HD) or 103 ((ITV HD) is not seen? then the set is not fitted with an HD tuner which is necessary to view Talking pictures, as this programme is transmitted on COM7, an HD Multiplex.
We live in Chelmsford, Essex. There has benn no change to our set up but overnight we now have very bad reception on BBC channels and no longer have any HD channels. We have a Samsung TV with build in Freeviewreceiver. Other channels like ITV and C4 are all fine.
I have reset the channels as described on this site but it has made no difference.
We use the Londontransmitter but it there is no difference when we connect to the Sudbury transmitter. It all worked fine - good BBC channels and HD channels but it has all gone wrong overnight.