All posts by jb38
Below are all of jb38's postings, with the most recent are at the bottom of the page.
Tim: Should have really have suggested this earlier, but if your source of interference is NOT of a UHF RF nature, then a simple highly effective test can be carried out using a small portable radio that has a LW band on it.
This is because long wave radios can act as great electrical interference source sniffers, this achieved by tuning it to a blank spot on the scale where no stations are being received, (e.g: Radio 4LW) then turning up the volume slightly.
You can then try it sitting close to a mains power socket prior to the time that the problem with reception starts, making sure that no excessive buzzing noises etc are heard, then noting if this situation has changed after the picture problem has started, this indicating that the source of the problem is mains borne.
Don't position it anywhere near to the TV though, as some of these can radiate all sorts of interference up to short distances away.
You can also use this type of device to check on faulty water tank thermostats etc, or anything that involves electrical contacts.
Mains sourced interference may be nothing to do with your problem, but thought it worth mentioning as a final suggestion.
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Andrew: I very much doubt it! as even Hunmanby which is very roughly in the same line between Oliver's Mount and you doesn't indicate as stretching as far as you, if though its easy to alter your aerial then its worth a try, you most likely having to use manual tuning on each Mux for a test, blanking the memory before doing so by scanning without the aerial being connected.
Hunmanby: BBC Mux Ch48 - ITV Mux Ch42
Oliver's Mount: BBC Mux Ch57 - ITV Mux Ch60 -HD service Mux Ch53 - ITV3 etc Mux Ch54 - others Mux Ch's 58 & 61.
Remember though that in both cases the aerial has to be vertically mounted.
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Tim: Just to clarify any possible ambiguity, when I referred to Radio 4LW I was really meaning NOT anywhere near to it, as anywhere near it would kill the receivers sensitivity for sniffing out interference.
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Mark A.: Yes, I agree that this would be a very useful facility, even if as on some sites the delete option expired after a few minutes or so, as that's just about long enough for anyone to suss out that they have maybe misinterpreted what someone has meant, this being very difficult on occasions!
Of course even without the above, I would be quite content just to have a preview facility which incorporates an edit option.
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Sunflower: Try taking out the Sky boxes RF input lead from your normal aerial "before" trying to alter the modulators RF output channel and see if that works, as if it doesn't and you are using the correct procedure, which you appear to be doing, then that's inclined to indicate a fault with the box.
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Brian Rawlinson: It would have been of assistance to know your location as reception checks etc could have been made, however apart from that the problem you are experiencing could possibly be linked to the fact that when transmitters change powers at switchover they go onto an 8K transmission operating mode, this causing problems with many sets, and with on some occasions it not being a rectifiable problem.
I tried to check the spec on your device but it doesn't give that info, but the fact that you have actually received something since switchover suggests that it is capable, but exactly how efficiently is another thing all together, as many sets have to have software updates to allegedly cure a range of 8K derived difficulties.
I will say that your particular model is no stranger to firmware updates, as many people experience problems with it and other Philips devices of this nature.
If you come back with your location (pref post code) the transmitter transmissions details can be checked on, as dependant on which transmitter is involved 8K might not be applicable to all Mux channels, and a manual tune for testing purposes can then be carried out on that ones that aren't.
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Lawrence: Yes, unfortunately that's the kind of problem that is inevitable when the main transmitters are on such a high power compared to the lesser ones, as in many areas its difficult to strike a happy balance between reducing the main ones but without killing off the weaker channels.
About the only thing that can be done in these circumstances, which I will say are only temporary until 23rd of November, is to use a booster with a variable power, using the trial and error way of just backing off the main channels a little bit at a time and no more, hopefully by doing this not having killed the weaker ones in the process.
Nothing else can really be done except to wait until November when the situation should correct itself, at least it will do for some, as stations operating variable transmission powers will always cause problems for many people.
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jacko: Basically its by keeping the Sky boxes RF output channel away from any of the channels used by Tacolneston Freeview service.
Take the normal aerial (from roof) plug out of the Sky boxes aerial input, then on the Sky boxes remote control press "Services", then whilst NOT looking at the screen press "4 - 0 - 1 - Select" in one smooth operation without hesitating between anything.
You should now see a list with RF output being mentioned, punch in any number at least two channels "AWAY" from any of these Tacolneston Mux channel numbers, 53 - 58 - 60 - 61 - 63 - 64.
Finally replace the Sky boxes normal aerial input and re-tune your analogue TV to pick up the Sky boxes new RF channel.
PS: Should you not see the selection list after going through the "4-0-1-select" sequence, then its because it wasn't done smoothly enough.
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Saturday 20 August 2011 9:04AM
Tim: Thanks for your update, and so long as the test was carried out whilst the picture was bad (very important!) then the booster can be excluded, and just like Briantist has previously mentioned, I also will be most interested in the diagnosis received from anyone you call in, as it really seems to be one of these type of problems that will only be rectified (hopefully!) by a site visit, as I suspect that other aspects exist of a nature which might appear as insignificant, but not! might also be applying.