My new FVp5000T keeps on reporting on ITV channel that the receiver is not receiving a signal or the signal is weak.
The diagnostics report 100% signal and quality then drop to 0% and 0% for a second so causing the error message.
Other TV's work fine - any ideas as to what's going on ?
I've done the obvious and checked the coax lead
You may have too strong a signal. Try a variable attenuator to reduce the signal strength. Reduce the strength to the point where the quality starts to decline then increase a bit. Check the other MUX are still stable.
There a reception problems all over on many models of box because of the weather. I lost COM7 from Oxford which has only just come back but dangling on the strength / quality cliff.
gomezz - 8 minutes ago »
There a reception problems all over on many models of box because of the weather. I lost COM7 from Oxford which has only just come back but dangling on the strength / quality cliff.
The OP is able to receive the affected channel on his other TV's. It would be a strange High Pressure uplift that only affects one item of kit. The OP doesn't say whether it's ITV-SD or HD in either case it will be a higher power PSB mux that is affected.
COM 7/8 is the first to suffer in this way because all transmitters share a very limited number of uhf channels and are of lower power than the others.
There were widespread issues with freeview over many parts of the country over late 31/10/17 and early 1/11/17. It seemed to cover most MUXes for me anyway in HP15, I have a 4000t.
Andy
Have a look at http://downdetector.co.uk/problems/freeview
hi Guys,
just to follow up on my 'weak signal' issue.
Last night 3rd Nov everything was good till about 10pm before I started to suffer from weak signal, only 103 HD seemed to be affected.
Other TV's were fine, so not sure if it's propagation and some weakness in the 5000T decoder design.
We're line of sight to Winterhill and can get a TV signal on some channels with an inch of wire in the TV antenna socket.
As we have about 10 TV outlets around the the house, we still needed a line amp which has 4 outputs which then feeds 3 three way splitters, the 4th output was feeding the 5000T.
So I switched the 5000T to the output of one of the 3 way splitters, it now reports 83% signal and 100% quality.
We'll see how this goes later today as I suspect the 5000T was getting overloaded.
I measured the signal strength into the 5000T using a Rigol spectrum analyzer and previously it was -45dBm it's now closer to -60dBm.
Previously I had found the original signal amp / splitter (installed circa 2000) was overloading to the extent some channels were not receivable and the signal compression was clearly visible on the spectrum analyzer. Changing over to a low noise Motorola cable line amp fixed the problem.
I wonder how many other houses are still using amplifiers from the analog days and suffering from signal distortion when the signal is already very strong ?
Due to the signal modulation scheme in use the line amplifier needs to be very linear especially if the incoming signal is already strong.
Regards Tim
timdf911 - 22 minutes ago »
I wonder how many other houses are still using amplifiers from the analog days and suffering from signal distortion when the signal is already very strong ?
Thanks for posting some actual measurements. Lots of people come here (and other Humax forums) puzzled as to why they have picture breakup when the signal strength is reported by the Humax as a 100%. In almost all cases turning down amplification or fitting an attenuator resolves the problem.
Note to Moderators: could we have a FAQ on signal strength please.
Just experienced this problem earlier this evening on BBC 2 HD where the weak signal message flashed up now and again (on my FVP-5000T).
On the other channels, there was no error message, just some playback stuttering.
Seems to have cleared up now so I am hoping this is indeed due to the weather.
Funny thing is I have never seen or experienced anything like this on the other TVs in the house where they are connected directly to the ariel socket.
I have taken note about the attenuator which I might resort to if the issue persists.
Icebun - 13 minutes ago »
Just experienced this problem earlier this evening on BBC 2 HD where the weak signal message flashed up now and again (on my FVP-5000T).
On the other channels, there was no error message, just some playback stuttering.
Seems to have cleared up now so I am hoping this is indeed due to the weather.
Funny thing is I have never seen or experienced anything like this on the other TVs in the house where they are connected directly to the ariel socket.
I have taken note about the attenuator which I might resort to if the issue persists.
Digital TV tuner design as in most things are a comprimise. If you make the tuners very sensitive they are able to give a perfect picture using a weak signal. The downside is when presented with a very strong signal the tuner cannot cope. Technically the input voltage level exceeds the level that the output follows the input linearly but at an amplified level.
In this case due to distortion the indicated signal level can rise, the much more important quality falls to near zero or rapidly fluctuates.
Your aerial does not have the same gain at all frequencies. If the UHF frequency used for the HD mux happens to beclose to the higher gain then this could be the issue. Additionally the error correction used on the HD mux is less able (used to increase the Mux bandwidth) to cope with external impulse interference.
A lower gain flatter response aerial like a log periodic may well be the best solution. Log aerials have excellent noise rejection. (The BBC use them extensively).
Less sensitive tuners are much more resistant to higher signal levels but unable to cope with weak signals.
In case 1 you just need a cheap attenuator.
In case 2 you need to resort to a superior aerial and/or extra amplification.
Give me the sensitive tuner every time.
Many of us have/had digital TV before DSO and as a result have high gain aerials and amplifiers. At DSO (switch off of analogue) the power increased greatly leaving a over amplified source we can do without and replace with simple passive splitting.
Thanks Graham for the technical lowdown.
A good insight into something I have just taken for granted.
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