All posts by jb38
Below are all of jb38's postings, with the most recent are at the bottom of the page.
Robert: What model of PVR are you using? but with regards to your suspicion about a possible post DSO issue having cropped up connected with the HDMI cable link, have you actually verified this as applying or not? obviously done by just temporarily coupling the two devices together via a scart lead, although it does have to be said that the superior HF characteristics of HDMI make it more vulnerable to being interfered with, so the cables used should be as short as possible as well as being of reasonable quality, this of course excluding cables seen with fanciful claims being made for them as well as being sold at inflated prices.
Another point I meant mention before concerning you having stated that your reception gets worse when it rains, a possible reason for this could be caused by the combination of the height of the mast in relation to your proximity to it, insomuch that the signal level received could be even more intense by the moisture in the air conducting the energy from the masts radiators more efficiently than if would be directly through air, this having the effect of making you appear as being even closer to the mast than you are, as indeed just like happens in any circuit where high voltages exist irrespective of whether it be 50Hz or 500Mhz.
A somewhat crude way to tell if this is happening is to place a metal rod on your window ledge and connect one end of a FET (high impedance) input voltmeter on to it, the other meter lead not being connected to anything unless the reading is very low, then clip it onto another piece of metal.
By the way older analogue pointer types are generally better for tests of this sort.
The test being, that provided the meter doesn't have any RF blocking measures in it like a capacitor having been placed across its input terminals then note the reading obtained in dry weather, then compare this to the indication seen when it rains, even better if the rain is on the rod.
Of course this "closer effect" when it rains referred to can completely reverse over long distances, where a signal can in many cases be reduced rather than enhanced for a variety of reasons.
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ptc: This can happen if your box has just about reached its limit for the number of channels its memory is capable of storing, hence when its unpowered they are lost.
Without having knowledge of the box being referred to carry out a complete factory reset on it, sometimes called default scan, then follow this with another auto tune.
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ptc: Should this be found not to have improved the situation then come back with the model of the box in question.
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Terry: Although you are located at 24 miles away from Winter Hill you could still be receiving a signal thats on the verges of being on the high side, and that will always affect HD transmissions before SD.
I notice you mention that you have an attenuator fitted, is this a variable type or is it fixed, and if the latter what db level is printed on it?
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Lesley: A signal level check can be carried out even on a blank screen, and so referring to the Panasonic, select a programme channel that results in a blank screen and press the following: menu - set-up - select and press on DVB tuning - select and press on manual tuning, then when it opens you will see a bar at the top with a mux channel number being indicated on the right hand side, using the up / down arrows on the large round button on the remote control keep inching it up or down until you come to Ch42 but do not press it as yet, because as soon as you have reached that number the strength / quality that the mux channel 42 is being received at should be indicated on the two bars below.
Make a note of what's indicated on Ch42 and then inch the channels up until Ch47 and likewise note the indications on it, as these two channels are the ones that are under your TV's reception threshold as far as resolving a picture is concerned.
The channels used by Hannington are: 45(BBC) - 42(ITV1) - 39(HD) - 41(SDN /10-ITV3) - 44(ARQA /11-Pick TV) - 47(ArqB /12-Yesterday ) and so using that procedure you can compare the strength / quality of the channels you see with those that you don't, and you only require one indication from each mux channel.
The indications seen on these two should be somewhat less than on the others that you can see, so maybe you could indicate what the difference is "particularly on quality" using only a couple for an example, as that would give an idea if a booster would assist or not, as if there is a large difference then it wont.
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bernard: And it would have been of considerable assistance in assessing the level of signal that you are liable to be receiving if you had indicated your location, pref post code or one from nearby, e.g: a shop etc, because although as was mentioned by Mike Dimmick your aerial will be lacking efficiency on Ch29 this will not be quite so important unless you are located at a considerable distance from the transmitter as well as residing in a known problem area.
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Yvonne: If your daughters flat is located in the lower down areas on the same level as the marina then she most likely wont be able to receive Freeview thanks to the residents having been somewhat foolishly given a choice where the replacement transmitter was sited.
However the only option she would then have is to use an online service "if" the flat is located in an area where that service exists, but it is still possible to use a smaller satellite dish kit indoors if your daughters window is Southerly facing and she is NOT located on the opposite side of the marina to where the Co-op building is situated, so if you could provide her post code or one from very nearby (a pub etc) then this could be checked out.
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Yvonne: Just out of curiosity, could you please clarify if the code you provided is applicable to your own residence or that of where your daughter is hoping to move into? as the content of my reply was based on it not being the latter, not of course that it would make much difference unless she was located in the slightly higher level parts of the town where the reception from the Whitby analogue relay isn't quite so iffy.
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Lesley: Unfortunately I could only use the check you carried on Ch45 & Ch47 on this test plus Ch41 from your previous posting, as although you did succeed OK in using the TV as a signal tester, Panasonic's being excellent for that type of thing, but you had only inched the channels up one at a time rather than repeatedly pressing the arrow button until you had reached each of the channel numbers shown on the list, excepting Ch39 that is unless your TV is capable of receiving HD, and its NOT just an HD Ready type which cannot.
By the way, this test that you carried out is about first thing that anyone called in to investigate the reason for poor reception would do but obviously using a signal strength meter rather than the TV, as signal strength / quality tests on each of the six multiplex transmitters that the station uses is the only way to assess the possible reasons for poor reception.
However, although it would have given a more complete idea of your reception if the readings obtained on Ch42 & Ch44 (+Ch39 if an HD set) had also been made, but the results on Ch47 is inclined to indicate intermittent problems being caused by trees, trees and Freeview signals not really mixing, and on a study around your area I noticed that its seemingly one where installers have pointed some aerials at Crystal Palace whereas others being directed towards Hannington, aerials mounted on tall masts coupled them facing in different directions always being an indication of a reception problem area.
The fact of you having lost ITV1 but not the BBC could be an indication of "same channel" interference from another transmitter, as the weather / atmospheric changes has already caused problems in some areas, and this is something that there is no cure for.
Maybe though you could complete the test by carrying out a check on Ch42 & Ch44, as 42 is on double the power of 44, and whilst you are at it try a check on Ch23 which is Crystal Palaces BBC1, although as its being partially received on the side of your aerial (Hannington 236 degrees / Crystal Palace 89 degrees ) it may be very weak, but it would be interesting to know if anything is received from it as its on 200Kw compared to Hanningtons PSB's 50Kw.
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Thursday 7 June 2012 9:46PM
Dave Lindsay: Well although what Mike Dimmick has mentioned regarding the removal of the Sandy's Southerly attenuation on the 27th is quite correct that's not exactly what my suspicions were aimed at, although there is a slight connection insomuch that the power of these muxes will require to be seriously reduced (or cut altogether) before any work can be carried out on the mast, "if" physical changes are on the cards to be carried out rather than other electronic methods, should they be able to achieve this.
You see the problem when dealing with commercial muxes is that they aren't obliged to report in the same way as would anything involving PSB muxes and with this making it difficult to get accurate information, even from my own contacts.
With regards to the notorious Ch48-51-52 should it transpire not to be a panel fault then it could also be that the power has been reduced for preliminary work being carried out, as I checked these three channels earlier on and although Ch48 & 51 have stabilised slightly to what they were yesterday there is still a solid zero on Ch52 , which in my long term experience is "not" being caused by anything other than something connected to the station, as pre-switch over when the commercials were operating on 20Kw indications like that were the order of the day in my area.
Needless to say I will not be advising anyone that's having a problem with these channels to upgrade their aerial "if" their reception was OK until recently, but just to wait until a few days after the 27th before re-assessing the situation.