All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
Andy: I wouldn't like to say with any certainty whether the Grenoside transmitter, if it were to come to fruition, would serve you. In general terms, a south-facing slope is just what you don't want for a transmitter to the north! So I doubt it will.
This is a terrain plot from you to the Crosspool transmitter:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location
Obviously the plotter samples ground heights at set intervals and as it's only a relatively short distance it may not be entirely accurate.
There's also a question of which channel to use. Refer to Digital UK Coverage Checker for your location:
Coverage Checker - Detailed View
UHF channels available for use by TV are 21 to 30 and 39 to 60. At your location only 50, 55 and 59 are free. 56 and 57 are used by Waltham for its lower-powered COMs. We already know that 50, 55 and 59 are used at Oughtibridge so they won't be available for use by Grenoside. Therefore, if Grenoside comes off my guess is that it will broadcast on 56 or 57, and even if you are just about in with a shot you "may" find that outside chance obliterated by Waltham.
And then there is the question of your aerial for Grenoside (I guess it's unlikely you will receive from it, but let's just say you will), you will have to receive other channels from where?
| link to this comment |
George Stephenson: At your location you could potentially have difficulty with Divis' COM4/COM5/COM6 channels (which carry, ITV3, Pick, Dave, 4Music, Sky News etc) because these are co-channel (same frequencies) as those of Darvel in Scotland and Caldbeck in Cumbria. The PSB channels (BBC, UTV, Channel 4, Channel 5 etc) are not shared. As you are right against the sea then then it's possible that the unwanted signals could affect your reception at some times.
Has the signal level dropped from what it usually is? There are seven channels you should look at:
PSB1 - BBC One
PSB2 - UTV
PSB3 - BBC One HD
COM4 - ITV3
COM5 - Pick
COM6 - 4Music
COM7 - BBC News HD
PSB3 and COM7 are only available with a Freeview HD receiver. COM7 is on lower power so might not be available to you.
If the problem is interference from Darvel or Caldbeck then the strength would be expected not to have reduced but the quality would have.
If you view the signal strength/quality screen on each channel, do so for a minute or so in order to see if there are fluctuations.
| link to this comment |
marion: If the VCR has two scarts then you might find that feeding the digibox into it and then the VCR into the TV works. Obviously the VCR will need to be powered on at the wall in order for the digibox picture to pass through it. The instructions for the VCR might detail different set-ups, including one where you feed a "decoder" into it, which is what you digibox is.
| link to this comment |
Richard: It's carried on "local" TV multiplexes and as such these serve one town or city which means they are more restricted in their transmission power and radiation pattern. So no, Mustard isn't likely to be broadcast in your direction, only to Norwich.
| link to this comment |
Fiona: Confirm whether or not 4G in the 800MHz band is operating in your area and perhaps coincides with the start of your issue.
The mobile operators have set-up a company called "at800" to address the issue of interference with TV reception and its contact details are here: Contact us | Advice or general enquiries | at800
I suggest you give them a ring and see what they say. If it could be 4G interference then they will send out one free filter per address.
| link to this comment |
tannya: An "Freeview" set-top box will not work with a satellite dish because Freeview is the terrestrial system (transmitters on the ground rather than a satellite in orbit).
A "Freesat" box will work with a satellite dish, Sky and Freesat being 100% compatible as far as the dish is concerned.
If you plugged the satellite dish into the back of the TV and your TV has a threaded F-connector which mates with the plug on the lead from the satellite dish then it might have the capability to receive Freesat. If, on the other hand, you used an adapter or changed the plug on the end of the lead to a push-in one then that won't work.
| link to this comment |
Peter Hughes: The quasi-national COM7 which carries BBC Four HD (and forthcoming COM8) multiplexes are as they will be for the next four or five years, Sudbury being without.
There is talk of BBC Three closing so whether BBC Four HD will take the place of BBC Three HD, I don't know; I know some have speculated maybe someone else can confirm more solidly either way.
| link to this comment |
Mike : See Digital UK Engineering Works:
Digital UK - Planned Engineering Works
Stockland Hill's status is "Possible weak signal" so don't adjust your set, it's probably the works that are causing your issue.
| link to this comment |
Friday 20 February 2015 7:12PM
John Luke: I suggest that if it's a yagi aerial then go for Group K. With the Group T "LTE" aerial you have gain on channels 49 through to 60 which isn't necessary. The wider the band of a yagi the more of a compromise it is. I say Group K because SC could use channels in the 20s in future.
See:
TV Aerial Tests
Gain (curves), Again
I write on here as a technical bod rather than an installer, so which it should be, I'm not sure. Or a log and amplifier maybe??
Here's a terrain plot showing two obstructions:
Terrain between ( m a.g.l.) and (antenna m a.g.l.) - Optimising UK DTT Freeview and Radio aerial location