All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Brian Murray: According to Digital UK, COM8 launched from Caldbeck only yesterday.
In which case, if you haven't already done so you should go to the manual tune screen and select/enter UHF channel number 35 (if there's an option for DVB-T or DVB-T2 then the latter should be chosen). Don't press the button to scan/add services straight away, instead wait and see what readings of strength and quality you get. If the going's good then add the channel.
According to Digital UK, power levels for Caldbeck channels are:
PSB1, PSB2, PSB3 - 100kW
COM4, COM5, COM6 - 50kW
COM7 - 31.91kW
COM8 - 35.8kW
We do not know whether COM8 is running on its full final power yet.
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Brian Murray: Have you confirmed that BBCB is tuned to Caldbeck (England) on UHF channel 30?
And, silly question, but the grid aerial is mounted horizontally and not vertically?
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Brian Murray: That's odd. So what BBCB(PSB3) is it tuned to? This information (the tuned UHF channel and/or frequency) is given on the signal strength screen. Go to 101 BBC One HD and view the signal strength screen.
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Tony: Purely on the information provided, it could conceivably be that the signal strengths are high to excessive, although this would be unlikely at such distance from the transmitter. HD signals tend to be affected before SDs with excessive signal. If you have an amplifier then turn it down.
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Brian Murray: What you're describing sounds like a TV which doesn't have a Freeview HD (DVB-T2) tuner in-built. Lots of people have been caught out by this. Are you sure it receives the HD channels itself or have you been viewing the HD channels using another tuner such as a PVR?
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Brian Murray: As you may know, Film4+1 used to be on one of the COMs (COM5 IIRC) and it's now on BBCB. So even though it's in SD you need a HD receiver to get it. The TV or box you are using for the test must have a HD (DVB-T2) tuner in-built, usually branded as being "Freeview HD".
Retuning is a waste of time if it's tuned correctly -- you need to ascertain that that's the case. So is the Samsung tuned to UHF channel 30 (545.8MHz or 546MHz) for BBC One HD? If it is, what happens with a different aerial?
Perhaps there's a known issue with your model that is causing it to forget Film4+1. Let us know the model number and one of the experts on here might be able to shed light on that.
That said, perhaps the issue is Film4+1 moving multiplex and some remnant of its old multiplex being stored in your TV, this only being cleared out by a factory reset. This still doesn't explain the poor reception.
A grid aerial has low gain (because it has no elements and has wide acceptance angle). So it would seem unlikely that you could possibly be suffering from too high a signal level into your TV. Where this is the case, however, it usually affects HD multiplexes before SD muxes.
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Bob Partridge: A location, preferably in the form of postcode, is imperative as it's a reception issue. If you live out of sight of the transmitter and where reception is predicted as non-existent then it may be a case of keep moving the aerial in the hope of securing a good spot and hoping it lasts.
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Brian Murray: This would seem to be odd. Perhaps one of the other experts on here can chip in.
Brian gets poor reception of PSB3 with a grid aerial. COM7, which is on lower power, is received OK.
Brian, where are you in CA14? A full postcode is really needed. Due to the terrain you may or may not be able to see the transmitter. So can you see it from where the aerial's mounted or not?
And what's the signal strength reading from the Samsung on C30?
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Brian Murray: Here's a terrain plot:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Line-of-sight could be obstructed all the way up to 2.5 miles which is Great Clifton. The grid aerial is probably not suited to such a location.
Remember that larger aerials "might" have been installed in order to receive pre-switchover digital signals which were on much lower power.
Different models from one manufacturer may have different menu systems, but I pulled this from the user manual of one current model:
MENU > Support > Self Diagnosis > Signal Information
For Caldbeck, if you get a yagi it should be a Group A, or a log periodic is usually wideband:
The Main Digital TV Transmitters (the 6 MUX transmitters)
Or using an existing aerial, install a distribution amplifier.
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Friday 12 June 2015 7:52PM
Tricia Camm: This is the plot between Ruswarp Bank and Bilsdale:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location