All posts by jb38
Below are all of jb38's postings, with the most recent are at the bottom of the page.
Nick: Re: your 05.10PM posting concerning signal strength reductions etc, I would strongly recommend that you keep the test as simple as possible by "only" using an attenuator in line with the aerial socket as was described, because if you attempt to reduce the signal by changing the voltage being fed to the home made booster then you are effectively bringing something else into the equation thus making it difficult to evaluate the results as its effectively dealing with the unknown as far as signal attenuation is concerned.
Another problem that could be introduced by this action being, that there is always the possibility of the signal passing through the amplifier becoming corrupted due to the RF transistor being used for amplification becoming unstable because of insufficient voltage on its collector compared to that of the high level of RF on its base.
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Lisa Brumhead: Have you checked to ensure that the volume control on the Freeview box is sufficiently advanced? this done via the Freeview boxes remote control.
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Lisa Brumhead: On re reading your posting, if by both you are meaning the Freeview box as well as the TV, then are you connecting the box straight into the TV via a scart lead?
You should also make sure that the "Mute" button isn't pressed on the Freeview boxes remote control, if though you have checked all mentioned and the problem still remains then try another scart lead.
It would also be of assistance if you supplied the model number of the Freeview box in question.
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andy: Your Sky HD box will have two input feeds from the dish and so for a test try swapping the rear "F" connectors over, if though its found that the signal still hasnt returned then leave the box in standby for about 3 minutes or so before disconnecting it from the mains, then after waiting for about 30 seconds or so reconnect it again and allow it to go through its usual searching for listings procedure once it has started to respond to the remote control.
Further advice dependant on results.
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C coates: You should carry out a signal level check using the undermentioned procedure.
If using a Standard or Sky+ box
(1): Press: "Services" - 4 - 6 and this will take you onto the signal checking screen.
If using a Sky+ HD box: (latest menu system)
(1): Press "Services" and you will see the main menu with "Options" being highlighted.
(2): Press the right arrow once to change from Options to "Settings" and press on once highlighted.
(3): Finally, scroll to the right to select and press on "Signal", the grey bars now displayed will show you the strength / quality of the signal.
Should a signal be indicated then it has to around the 55% (or equivalent of) minimum level to resolve a picture and especially where the quality is concerned, because if the quality is observed to be under the signal strength then that generally indicates that the dish requires slight re-aligning, this usually (although not always!) being rectified by the dish being moved the merest fraction either way in its horizontal (right to left) plane.
If though nothing is being indicated, then the dish could be a bit too far out of alignment for the aforementioned to apply.
Further advice dependant on findings.
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Nick: Sorry, meant to add this to my reply.
However, put simply as it can involve a lengthy explanation, but what you refer to is actually something that was quite frequently heard in a large number of older CRT sets of the somewhat less costly types when the contrast was set on the high side, and with the problem basically being caused by poor design of the power supply allowing the effects of the "maximum current drawing" white level pulses of the video signal to be introduced into the audio circuitry by insufficient levels of filtering, this being why you hear the buzz level changing with the content of the picture.
This type of problem was not really noticed quite so much when the TV was being used for analogue reception via an aerial as the sets auto-gain circuitry kept this level under an element of control, but when a video signal is being fed into the set via the scart socket this control is bypassed thereby placing the circuitry at the mercy of the incoming signal level, and because a Freeview boxes video output is not adjustable in the same way as can be done with a Sky box (three choices of contrast) the only way of compensating for this is on the TV is by reducing the contrast level of the picture, unfortunately on some sets this resulting in the picture having a slight wishy-washy appearance.
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andy: Thanks Andy, and pleased to hear that this has rectified the problem, but though I would like you to use the undermentioned procedure just to ensure that the lead thats presently being used in the LNB2 position is OK, because if anything was amiss with that input such as water having entered the "F" connector on the dish, it would show up as soon as you try to record anything.
If using a Standard or Sky+ box:
(1): Press: "Services" - 4 - 6 and this
will take you onto the signal checking screen.
-----------------------------
If using a Sky+ HD box: (latest menu system)
(1): Press "Services" and you will see the main menu with "Options" being highlighted.
(2): Press the right arrow once to change from Options to "Settings" and press on once highlighted.
(3): Finally, scroll to the right to select and press on "Signal", the grey bars now displayed will show you the strength / quality of the signal.
If the indications are similar on both sets of inputs then all is OK.
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geoff: Just to add to that said by Dave Lindsay, Sky and Freesat dishes are exactly the same in the technical sense and a dish is just generally called a Sky dish by habit, as a Sky box could also use a dish installed for Freesat purposes.
EPG (electronic programme guide) just indicates the order that the channels are arranged in by each respective service and although for example ITV3 is received on 119 on a Sky box and 115 on a Freesat box the programme is received by both boxes on exactly the same transponder frequency.
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fred wiseman: Programmes of that nature always involve a subscription irrespective of what mode they are received on.
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Saturday 16 March 2013 6:32PM
Nick: Basically yes! this based entirely on what you have reported with regards to the signal being strong etc.
But as far as the PSB channels being lost are concerned, if the action of selecting BBC1 results in a blank screen then the "only" way of determining the cause is by following (exactly) the manual tune test procedure as described in my reply on the 12th @ 07.53PM.