All posts by jb38
Below are all of jb38's postings, with the most recent are at the bottom of the page.
Steven Ellson: As this is a reception query then its essential to have knowledge of your location, a post code or one from nearby, as you could be located anywhere from John O Groats to Lands End.
But regarding your aerial, are you meaning that you have an indoor aerial of the set top type that has a booster built in?
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Ron Crisp: I realise that you directed the question at Briantist, but if I could just answer insomuch that on the first part of your query the answer is yes, but as far as the second query is concerned it really depends on whether or not you consider paying £120.00 per year is worth it purely to be able to use the recorder, as that's all it covers and not any of the basic package channels that you had before.
A Freeview PVR would be a better and less costly bet "if" you had a suitable aerial installed.
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Mike O'Pray: If you see ITV3 mentioned on the EPG list whilst on the Panasonic recorder then go into its signal strength check screen and have a look at the level being indicated, as a signal must have been picked up or EPG10 would be missing from the list, so a signal is likely there but just under the level that can resolve a picture.
The diplexer (or combiner) is usually in a red (but can be grey or black) plastic box strapped to the mast pole, and you should see the coax lead from each of your two aerials going into it and one coming out downwards towards the roof or wherever.
The two programmes I mentioned are (or should) be seen on the EPG number channel listing, 11 being Pick TV and 19 being Dave, but if these numbers are not seen then you might not be picking up mux Ch52 either, that is as well as Ch51.
As its not known if your aerial is wideband or not, "if" though you can see the end of the long square horizontal bar that supports the elements check if you can see a red square plastic blanking plug on the end that faces Sandy, and if you can then that's an original aerial and will require changing to a wideband type such as a log 40 or similar, if though the end piece is a black plug then its a wideband aerial.
What you require to do as far as improving your situation is concerned is removing the diplexer and having the cable from the Sandy facing aerial coming straight down into your house, and the Sandy aerial being changed to a wideband version if its not already that.
By the way the manual tuning instructions are on page 71 of the Panasonics user manual.
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Mike O'Pray: This is a link to the Log 40 that I referred to as I forgot to attach it to the bottom of my reply, should you want anything mentioned clarified a bit further do not hesitate to ask.
Online TV FM DAB Aerial sales
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Mike O'Pray: If I could just further add for purposes of explaining / emphasising why the diplexer presently installed will be detrimental to your reception and likewise has to be removed.
Diplexers are simply twin input dual band filters that only allows two sets of channels within a defined frequency range to pass through, and the type that's installed in your aerial system will be allowing channels from Ch21 - 37 to pass through on its No1 input and with anything above that range being attenuated, whereas the diplexers No2 input will only be allowing channels from Ch39 upwards to pass through and will attenuate anything under that.
As you will probably gather, that as your Sandy aerial is on the diplexers No1 input then anything above Ch37 will be attenuated, which of course includes all of Sandy's commercials, namely Ch48 / Ch51 / Ch52 and the very ones you are having trouble with.
That said, these channels will of course be allowed to pass through the diplexers No2 input which starts at Ch39, this being why Dave Lindsay had mentioned about turning the Waltham facing aerial around to face Sandy, which of course would improve the situation but only in a second best fashion, as diplexers have insertion loses plus a signal level tapering off effect near to the crossover points between the two frequency ranges covered, and so its always better without anything being installed except possibly a booster, but only should this prove as being necessary.
Taking the explanation of how a diplexer works into consideration you can maybe understand why this device is totally unsuitable for receiving signals from Sandy because of its channel span range of Ch21 - Ch52.
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Mike O'Pray: Just noticed that you had replied.
What you have said with regards to your plan of action is correct, insomuch try and check the colour of the square plug on the end of the aerial cross member and if its red then another aerial of a wideband type is called for.
All you require to do in a diplexer is prise off its plastic cover and disconnect the coax from the Waltham facing aerial and tape the ends up out of the road, then take the coax connection from the Sandy facing aerial off the the diplexers input tags and join it onto the diplexers output tags where the feed to the house will already be joined onto, in other words the two coax leads joined in parallel.
By the way the only reason for you receiving more channels via the scart from the DVD will be because of either (1) the Panasonic has a more sensitive tuner, or (2) because when the signal is looping through the Panasonic then into the TV its being attenuated slightly, this effect always noticed more in weak signal areas.
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Mike O'Pray: If I could just add a qualification to the plan of action insomuch that if its found that you do have an original group A (red end) aerial, then even without changing it you would most likely find that you could receive the missing channels by simply disconnecting the Waltham facing aerial and by-passing the diplexer, as that device alone will be killing off the reception of the commercial channels far more than the fact of the aerial operating out of band, as aerials out of band will still work but with their efficiency dropping off the further out of band they are required to operating in, although with the commercial channels upping their power to 170Kw that would more than compensate for the out of band deficiency.
Should I have known that your two aerials were linked together I would have mentioned right from the start that the system had to be changed, albeit of course that you were unaware of why it would be having such a detrimental effect on reception of the commercials.
In other words, to make life easy if you know someone with a ladder that can access the diplexer then maybe you could get them to by-pass it, even if its just done by taking the coax connections off the terminals (usually always screwed) and joining the coax from the Sandy facing aerial onto the coax feeding the house using a small terminal block, because as long as the terminal block is inside the casing for protection against water then its perfectly OK.
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ErwinH: If you can receive all the channels perfectly OK with a set top aerial then this is simply because of either (1) The signal you are receiving via the communal aerial is excessively high and is partially blocking the Sony's tuner, or (2) that the distribution amplifier used by the communal aerial system is itself being overloaded and sending out an defective signal, as you are indicated as being only 12 miles away from Sandy.
I feel though that its No1 that's the cause of your problem, and the only reason that a set top aerial works is because that it will not supply the same level of signal into the tuner as would be obtained from a communal aerial system (or roof if not communal) not that terribly far away from the transmitter, and so you should purchase an attenuator to place in line with the Sony's aerial socket, one of the variable types with a range of 0 - 20db would be fine, as although I feel that a fixed attenuator of about 10db would be suffice its very difficult to judge as to whether it would be or not as it depends on just how strong the signal is.
By the way you cannot reply on the signal strength / quality indications seen on Freeview devices that are operating with an excessively high level of signal, as the signal data gets corrupted in the tuner which results in the system used for measuring the strength / quality giving false readings, these always being low.
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Loges: You are indicated as being located at only 4 miles away from the high powered Emley Moor transmitter so in theory the signal should be very strong even if using a set top aerial, however going by what you have said about the past I suggest that for a test you try and borrow a Freeview box, coupling it into your TV via a scart lead, and should you not be able to borrow a set top aerial then even a short piece of wire (about 12") pushed into the inner part of the aerial socket on the box should be suffice for reception in your circumstances.
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Thursday 17 May 2012 2:59PM
Dave Lindsay / Mike O'Pray: By-passing the diplexer and using only the aerial that faces towards Sandy is exactly what I said in the latter part of my posting made this morning @ 08.19am, the removal of the diplexer being particularly important as you don't want anything of a signal filtering nature incorporated into the aerial system.
And with regards to the aerial used for Sandy, if it is an original group A aerial installed that pre-dated the start of Ch5 let alone Freeview, and with it never having been updated at any time, and if this is the case then obviously as you drift upwards from the end of the frequency range covered by a band A group aerial (Ch34) then signal levels received will not be quite as high as they would be with a wideband aerial, however irrespective of the aerial group fitted Mike has only complained about the reception on ITV3 on Ch51 and not anything else, so if by any chance the aerial is still a group A and programmes on mux Ch52 such as EPG11 - Pick TV or EPG19 - Dave cant be received either then the aerial will require to be changed to a wideband type.
Mike O'Pray: Regarding the programmes I mentioned, can you receive those two channels? and have you had the aerial changed since analogue days when Freeview had first started?