All posts by Dave Lindsay
Below are all of Dave Lindsay's postings, with the most recent are at the bottom of the page.
steve: The likely answer is never as the Commercial broadcasters do not wish to invest in transmitters at 1000 or so small sites like Dallington Park. They achieve around 90% coverage of the population from about 80 sites nationwide. They were invited to increase their coverage but declined. The cost of broadcasting from the relay sites would roughly double their costs of transmission.
They work on a commercial basis where they generate revenue from advertisers. The objective is therefore to get as many people to view the adverts as possible at the lowest possible price.
See here for a fuller explanation:
Will there ever be more services on the Freeview Light transmitters? | ukfree.tv - independent free digital TV advice
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Frank Sanjana: I'm assuming that you're receiving from Hannington. If so, then the Commercial channels will remain on low power until 4th April for SDN (which carries ITV3 and others) and until 18th April for ArqA and ArqB which carry Pick TV, Yesterday, Dave, Film4, Sky News and others.
The missing channels you identify are all on ArqB multiplex and you need to try manually tuning to C47 for them.
If you have a signal booster, you should try removing it.
You may be able to get all channels to work, or perhaps at least get Sky News and Food (ArqA) to be more solid by putting an attenuator on line with your aerial lead. I am referring to a device such as this: www.ebay.co.uk/itm/VARIABLE-ATTENUATOR-TV-SIGNAL-REDUCER-20dB-3-5-6-9-10-12-15-18-DIGITAL-FREEVIEW-/370552240392
The issue could be that there are now high power digital signals BBC and ITV1 etc when there wasn't before. These could be acting to desensitise your receiver and in so doing it doesn't "see" the lower power channels you're having problems with.
The attenuator will reduce the level of all signals. A variable one such as the example I've given will allow the level of reduction of signals to be varied so as to see if a happy medium where all will work can be arrived at.
So basically the hope is that the level of the high power signals can be reduced sufficiently (to increase the sensitivity of the receiver) *and* that the degree of attentuation does not reduce the level of the weaker signals too much so as to not be receivable.
There is therefore no guarantee that a balance can be struck.
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Sarah: On the basis of what JimF has said, to increase your chances, your radio probably needs to be on the side of the house facing Exeter with the clearest possible view in that direction. Try taking it upstairs on that side of the building and see what sort of signal strength you get on each multiplex.
St Thomas broadcasts BBC National (12B), Digital One (that's the commercial national multiplex and it's on 11D) and South East Devon (11C).
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Sarah: Having taken it from the shop all tuned in, then the worst thing you can do is rescan.
Once tuned, the radio "knows" what channels are available and will receive them when sufficient signal is available to it.
Rescanning wipes its memory so it no longer "knows" what's available and you then have to get this list of what it "knows" back by repeated re-scans until you have them all.
Where you have the radio in a location where it is tuned to a particular station but where there is insufficient signal to hear the station, then retuning cannot possibly have a positive impact in that it will not enable you to hear the station. The only outcome it can have is a negative one (i.e. you loose the station in question from the list).
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pete: Is your aerial directed at the Steyning transmitter (your aerial will be vertical) or is it on Midhurst (aerial will be horizontal)?
If your aerial is on Midhurst, then you shouldn't be tuned to Steyning and its existance will not improve your reception from Midhurst.
It is worth confirming that BBC and ITV1 are tuned to the transmitter to which the aerial faces.
From Midhurst, BBC is on C55 and ITV1 on C61.
From Steyning, BBC is on C59 and ITV1 on C50.
Therefore, when it is scanning, Midhurst is the first BBC signal (of the two transmitters) and Steyning is the first ITV1 signal. I wonder, therefore, if this could have resulted in your main ITV1 signal being tuned to Steyning when in fact it should be Midhurst.
You should be able to confirm either way by viewing the signal strength screen whilst on each channel; most receivers give this information.
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Derek Green: The vertical element of the COMs will only be introduced on 18th April when they change channels and when their ERP is increased.
The vertical element of the PSBs' signals has been introduced at switchover.
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Kim V: Confirm that the jerky BBC channels are coming in on channel 24 and not 46 which is Winterborne Stickland or even 61 which is Mendip.
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Dino: In circumstances such as yours, you would be best advised not to retune because the only possible outcome is that (most likely) you loose the programme channels from your receiver or you get them back. Crucially, the act of retuning cannot have any affect on getting them back, therefore they would have come back anyway if they are back after retuning.
The act of retuning is therefore like shooting oneself in the foot. Only where there is reason to retune, such as a change of channel should retune be carried out.
The only way you are going to get it back is to repeatedly manual tune to channel 31 until it comes back, whereas had it been left, you could simply have select CITV to see if it was back.
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Monday 19 March 2012 10:33AM
Simon Miller: It should improve come switchover.
Tunbridge Wells is traditionally a "Group B" transmitter. That means it uses frequencies in Group B which is roughly the middle third of the band used for television.
Consequently, Group B aerials are likely to have been fitted. They are aerials that are much more sensitive around Group B frequencies.
Unfortunately, some of the pre-switchover digital channels are outside of Group B, them being higher. This means that your aerial (if it's Group B) won't "hear" these as well. The affected multiplexes are Mux 1, Mux 2 and Mux D; see the top of the page for the services that these carry.
After switchover, all multiplexes will use Group B frequencies. So I would not replace the aerial because the current one should work OK from 13th June.