Feedback
Brian Butterworth published on UK Free TV For the last six years, I have answered many thousands of personal emails that you have sent to UK Free TV.
Sadly, I am unable to offer this personal service at the moment.
Until I can restore this service, please can you leave any questions you have on an appropriate page, where they will be answered as soon as possible, or below, if you can't figure out where to ask.
I look forward to your questions!
Help with TV/radio stations?
In this section
Saturday, 22 September 2012
L
lez8:56 AM
what happens when only one channel says no signal recieved all others are working fine
| link to this comment |
J
jb385:35 PM
lez: Its impossible for anyone to be able to answer this type or query without a post code (or one from nearby) being provided, plus slightly more information regarding the type of aerial being used, eg: set top, loft, roof mounted or a communal aerial system.
| link to this comment |
W
William5:44 PM
I only get 18v at the master aerial point when I switch the sky box on and the sat cables are connected from wall to box when the sky box is switched off or I take the sat cables out the box I get no voltage at my aerial
| link to this comment |
J
jb386:05 PM
William: Just to reiterate on a point, no voltage whatsoever should be appearing across the master aerial socket and this is likely to be the source of your problems.
Although I have never ever experienced this sort of thing happening and with knowledge of the circuitry don't actually see how it could, but purely for purposes of elimination test for voltage across the Sky boxes (test made on box) normal aerial socket, there should of course not be any!
Remember not to use a AC setting on your test meter as it will result in any DC readings taken being far higher than they really are.
| link to this comment |
W
William7:06 PM
Is the 18V going back towards my aerial when the box is switched on not a back feed through my sat cables into the triplexed unit as the voltage only appears when there plugged in and the box is powered up.
| link to this comment |
W
William7:19 PM
When you said the sky box sends 18V DC to the LNB for polarity switching purposes is that not why I am getting the voltage on my triplexed unit as its a combined unit hence the reason for the isolated coax point in the room
| link to this comment |
J
jb389:00 PM
William: Yes it could well be, but you had mentioned that the bedroom return was on a separate module and which I assumed was not connected to the main plate, but is it?
However these wall plates aren't completely standard and it depends on the manufacturers technical spec of the plate, and so if it has a type number printed on it maybe for reference purposes you could supply it.
But though irrespective of that, there should never at any time be voltage appearing on a coax aerial socket designed to feed into a TV, and the reason for me requesting that you carry out a test by removing the "F" connectors from the box one at a time was because I suspected that there was some form of bridge taking place between the Sky boxes LNB connection and the main aerial socket inside the wall plate, and that was where the voltage was coming from, because if this is happening then it shouldn't unless the plate was designed to be used with an isolating filter connected to its master output.
By the way, the 18 volts referred to only applies if its left on certain channels, as 13.6 volts is the norm if the box is on it menu screen.
| link to this comment |
J
jb389:37 PM
William: Re: bedroom wall plate being isolated, with the aid of your test meter you can find out if the isolater is for that purpose or not by measuring if any voltage is present on the rear coax where its terminated on the plate as sometimes these plates are isolated for the reverse reason, insomuch to stop a piece of defective equipment connected into the aerial socket from sending a voltage back along the communal line.
| link to this comment |
Sunday, 23 September 2012
C
Chris Bowden12:46 PM
jb38: Lost ITV1 and others? Dont let them fob you off by blaming the weather, your aerial, your set. your box not reset. Its all lies. The strength of the signal goes up and down like the proverbial.....!
CHATTON transmitter is the worst!. Had Freeview since it started, no problems till this year, recently ITV1 is the worst. Can get good transmission for some parts of the day then nothing. No new buildings or trees, good reception on other channels and even ANALOGUE. so it must be the signal or perhaps Santa parking his sliegh on the roof at certain times of the day. Tried all the helplines and website which are (in my case) about as much use as a chocolate teapot.
| link to this comment |
Chris Bowden: Santa only comes on 25th December and therefore is not likely to affect reception as switchover completes this Wednesday. On that date the power of the signal whose reception that is intermittent for you will be boosted to that of the current post-switchover BBC and equivalent to the soon-to-be former analogue.
The nature of digital reception means that a receiver requires the signal to be above a particular threshold level. Signals vary a bit over time. Thus, where the signal level changes every so slightly from "just above" the threshold to "just below" it, then the difference in the picture will be marked in that it will be available at times and not others.
The affect of the same change to an analogue signal will be a marginal change to the picture and perhaps not noticable by the viewer.
The lower power digital signals that are present before switchover mean that some (closer to the transmitter) will be able to pick them up, others will be too far away and won't be able to receive them, and then there will be some for whom it will be intermittent.
Perhaps a replacement aerial will provide a more reliable service for those whose reception is intermittent, but this is likely to be unnecessary post-switchover.
| link to this comment |
Select more comments
Your comment please