All posts by Chris.SE
Below are all of Chris.SE's postings, with the most recent are at the bottom of the page.
mike:
Brian Mathieson:
Mike, you may not have spotted that Brian's post was in 2012! But for the record, in the main, there is 3 transmission sites that'll cover most of your area, depending on precise location.
The 3 main multiplexes are carried by the Plympton transmitter roughly due E of Plymouth, which should give the more reliable signals, and Caradon Hill roughly NW, rather further away but should give fair reception. They are -
BBC National on Block 12B: 225.648 MHz
D1 National on Block 11D: 222.064MHz
SDL National on Block 11A: 216.928 MHz
Plympton also has a Local (commercial) multiplex on Block 12D: 229.072 MHz which carries BBC Radio Devon as well as some commercial stations
Whereas Caradon Hill has a Local (commercial) multiplex on Block 11B: 218.640 MHz which carries BBC Radio Cornwall as well as some commercial stations.
A Relay transmitter at Torpoint (Withnoe lane) aka Poron, roughly WSW from you, carries BBC National Block 12B, D1 National Block 11D and the Local multiplex on Block 12D.
So if you want BBC radio Cornwall, you might need a directorial aerial pointed at Caradon Hill to get reliable reception, otherwise depending on precise location, type of building and local "obstructions", the Plympton transmitter might be the best bet, a single Dipole may well do. You might be lucky and still get Caradon Hill reliably with a dipole, you might even get Plympton reliably with a directional aerial (say a dipole+reflector) pointed at Caradon Hill. Very often it's a case of trial and error.
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T mills:
Whilst you are well within the coverage area, you aren't in the best of locations for really good reception especially of the COM multiplexes. Your mother is better located and should have good reception except for COM7 where it'll probably be variable. Which channels are you having problems with?
See Channel listings for Industry Professionals | Freeview for which channels are on which multiplex. Check that other channels on the same multiplex(es) as the ones you have a problem with have the same issues.
Have you changed anything in your installations?
Neither Freeview nor the BBC are reporting any current transmitter problems and there's currently no Planned Engineering listed. There was Planned Engineering back in November with "Possible weak signal" and if you retuned or your set auto-retuned when you have no signal or badly pixellated pictures (never a good idea as it often clears correct tuning) it's possible you might have got tuned to another transmitter with poorer signals as several can be received in your area (but not as well as Sutton Coldfield).
So it's worth checking in your TV's tuning section that you are tuned to the correct UHF channels for Sutton Coldfield. All the multiplexes are C43, C46, C40+, C42, C45, C39+, C55, C36/C48 that's in the order BBCA/PSB1, D3&4/PSB2, BBCB HD/PSB3, SDN/COM4, ArqA/COM5, ArqB/COM6, COM7 and Local L-BRM.
Any aerial or cable degradation will also affect reception (not necessarily always affecting all multiplexes) so I would check that your aerial seems intact and pointing in the correct direction - bearing 317/8 degrees (~NW) and that your downlead looks undamaged (especially if it is old, and not flapping in the wind). Also check all your coax plugs, connections, flyleads etc, unplug connectors check for corrosion or other problems and reconnect them. Flyleads are a common problem, try swapping/changing them. See what signal strengths and quality you are getting for the multiplexes (groups of channels) shown in your TV's tuning section.
Problematic connections, water ingress etc. can seem to affect reception of just an individual or several multiplexes.
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Sean :
Whether this might help, see Channel listings for Industry Professionals | Freeview for which channels are on which multiplex.
And, in the multiplex order BBCA/PSB1, D3&4/PSB2, BBCB HD/PSB3, SDN/COM4, ArqA/COM5, ArqB/COM6, COM7, Local multiplex, the UHF channels for Crystal Palace are as follows
C23, C26, C30, C25, C22, C28, C55, C35 (London Local mux).
Try a manual tune on C55 &/or C35. Autotune sometimes misses weaker signals.
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David Skillen:
Is the recorder able to record BBC4 HD and BBC News HD (106 & 107)? Maybe the recorder is not receiving the channels on the COM7 multiplex on UHF channel C55.
See Channel listings for Industry Professionals | Freeview for which channels are on which multiplex.
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Jon Scaife:
The short answer is No, it's nothing to do with 5G. There are no 5G transmissions in the 700MHz band (those just cleared next to the frequencies for TV channels). The frequencies haven't even been auctioned yet. The only 5G is on much higher frequencies (~3.4GHZ) which is currently only used in some central urban conurbations.
PBS America is on the ArqB/COM6 multiplex. See Channel listings for Industry Professionals | Freeview for which channels are on which multiplex. If this is a reception issue then you should have identical problems with other channels on the multiplex.
How long have you been having the problem? Reception of any multiplex can be affected by many factors, location being one of them. We really need a full postcode to look at your predicted reception.
If you have a fault on your installation, that can appear to affect reception of one multiplex but not others!
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Anthony W Peerless:
My sincere apologies for missing your response to my previous reply to you a few weeks ago. If you happen to read here again, here is a bit of additional information which may help.
C35 is the Local Multiplex. As mentioned previously, see the channels carried on each multiplex. The missing channels above 105 (esp.106/107 BBC4 HD and BBC News HD) and the others, are on that (generally) weaker signal COM7 on C55.
Have a look in the tuning section of one of your other sets that is receiving C55 COM7 and make a note of the Signal Strength & Quality (or BIT Errors - BER) for C55 and compare it to the BBCB HD multiplex on C30. If you post the figures, I might be able to post some constructive comment.
Loft aerials can also affect the reception of individual multiplexes due to a variety of this that can disrupt signals, metal objects in particular - lead flashing, flue pipes, also water tanks, solar panels, partition walls and the like. Sometimes a minor adjustment to aerial position can improve things (or make them worse!). The bearing of Crystal Palace at your location is 35 degrees (about half way between NNE and NE) and according to the Freeview Detailed Coverage Checker you ought to get good reception of COM7 (but that is with an external aerial).
I'll try not to miss any reply if you happen to make one.
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nicky26:
RTE1 along with RTE2 & TG4 which are on the NI Mux, all moved LCN in the Channel list when 24 channels where moved back in early November. Any retune may have allocated them in the wrong place (have a look in your 800s). They are now on 52,53,54 that's TG4, RTE1, & RTE2.
See Channel listings for Industry Professionals | Freeview for which channels are on which multiplex.
The NI mux is on UHF C48 which you can try manually tuning if an automatic tune hasn't picked up the signal.
Post back if you still have problems. Happy New Year.
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colin Tate:
Hi Colin. First to clarify, UHF C33 is the SDN multiplex which is not an HD multiplex. The BBCB HD multiplex on C35 is the only HD multiplex transmitted from Selkirk. The temporary COM7 is the other which is only broadcast from 25 main transmitters in the UK.
You do need a receiver with a HD/T2 tuner to get HD multiplexes, but if you are getting the the ArqA & B (COMs 5&6) multiplexes OK, you shouldn't have any problem with SDN/COM4. However a full postcode is needed to check the predicted reception at your location to be sure there aren't any specific reception issues related to SDN/COM4.
Have a look in your TV's tuning section and see what Signal Strength and Quality (or BER) you get for the PSB1 & 2 multiplexes compared to COMs 5 & 6 and post the figures.
There doesn't appear to be any current faults listed by Freeview or the BBC and the transmitter isn't on a Planned Engineering list (that doesn't mean there isn't an unreported fault but I would have expected to see more posts in various places if there were).
See Channel listings for Industry Professionals | Freeview for which channels are on which multiplex.
How long have you had the problem with C33 & C35?
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Ian Grice:
The main BBC FM transmissions for your area come from Sutton Coldfield and the BBC aren't listing any faults. There's no reason or plans AFAIK for FM power to be reduced, other than for maintenance and there isn't any listed at present. Are you sure no nearby large buildings or trees have popped up on the line-of-sight by any chance?
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Wednesday 23 December 2020 12:20AM
Alan:
Are any other channels missing? See the channel listings link and advice in the post before yours.