- This topic has 24 replies, 12 voices, and was last updated 9 years, 8 months ago by
.
-
Posts
-
If the signal was too strong it should show at 100% but I get between 72 and 84%. I will give attenuator and splitter a try. I have both in my spares box.
Transmitter is considered a main but actually acts as a relay. No faults are reported according to the web site.
viccot – 44 minutes ago »
If the signal was too strong it should show at 100% but I get between 72 and 84%.
No sorry that is not correct; if the tuner is receiving a very strong signal then it can report a signal strength well below 100%.
So, based on above discussion, which is more important signal strength or signal quality and how would either of these cause the 4000T to consistently start recordings 4 to 5 minutes late for the majority of recordings as I am experiencing as well as the pixelation , even though my 9300T starts all recordings on time and no pixelation on the same aerial feed ?
Any thoughts greatfully received.
giverny – 7 hours ago »
So, based on above discussion, which is more important signal strength or signal quality and how would either of these cause the 4000T to consistently start recordings 4 to 5 minutes late for the majority of recordings as I am experiencing as well as the pixelation , even though my 9300T starts all recordings on time and no pixelation on the same aerial feed ?
Any thoughts greatfully received.
Signal quality is by far the most important measurement.
The most common cause of this is that when you auto tuned the box it tuned into more than one transmitter. This would have given you channels with a lcn of 800 and over. Note depending on the uhf channels that your multiple transmitters use for their mux, the ones over 800 could be the ones you should be using. In this case it’s not going to help just deleting these, as you may be left with mux from different transmitters. This creates issues with the accurate recording signalling used by broadcasters.
The solution is very simple.
Identify your local transmitter by entering your details here.
http://www.digitaluk.co.uk/industry/About_DTT/The_postcode_coverage_checker
The most likely transmitter will be top of the list. The grey numbers are the UHF channel numbers you want. Make a note of these and note which are HD.
Next you need to select and delete all your existing Radio and TV channels and delete them.
Now tune each of the above MUX in turn using manaual tune (DVB-T for SD, DVB-T2 for HD) and save each scan.
I don’t have the actual box but the actual steps should be fairly obvious. Hopefully someone with the actual box will assist further.
Sadly manual tune was the first thing Humax got me to try and it made no difference. My box only auto tunes to one transmitter in any event.
I agree 100% with Grahams comments above.
I would just like to add that I find the easiest way to remove all stored channels is to run an auto search with the aerial removed. This clears the way to perform a clean manual tune on the selected transmitter.
grahamlthompson – 17 hours ago »
Stephenesque – 4 hours ago »
A splitter should have given you a better result than loop-thru so that deepens the mystery. I use a passive splitter on my 2000T with excellent results.
With the splitter I had signal strengths of 1-70%; 2-67%; and 3 was only 48%.
After I connected my 4000T directly, my signal strengths increased to 1-84%; 2-85% and 3-78%
Signal strength has no effect on the picture when digital modulation is involved, unless it falls so low the built in error correction cannot cope. The effect in this case is obvious (the picture breaks up into a pixellated mess, and the signal quality varies dramatically) . The signal quality is the important number. A quality of 100% means that none of the built in error correction is required to produce a perfect picture.
The general accepted figure for the ideal signal strength (metering varies with individual box models) is reckoned to be about 60%. This avoids problems with sensitive tuners not bein able to cope with high signal levels, where clipping the peaks of the analogue carrier can produce distortion of the output signal. In this case high levels of signal actually look low, down to the distortion produced by the signal clipping.
I can’t explain it then, as with and without the splitter my notes show that my signal quality was 100%.
All I do know is that when I used the splitter, I had a score of unwatchable and failed recordings in a week.
Since I removed the splitter and looped through to the TV I have had none in 3 months.
Stephenesque – 2 hours ago »
grahamlthompson – 17 hours ago »
Stephenesque – 4 hours ago »
A splitter should have given you a better result than loop-thru so that deepens the mystery. I use a passive splitter on my 2000T with excellent results.
With the splitter I had signal strengths of 1-70%; 2-67%; and 3 was only 48%.
After I connected my 4000T directly, my signal strengths increased to 1-84%; 2-85% and 3-78%
Signal strength has no effect on the picture when digital modulation is involved, unless it falls so low the built in error correction cannot cope. The effect in this case is obvious (the picture breaks up into a pixellated mess, and the signal quality varies dramatically) . The signal quality is the important number. A quality of 100% means that none of the built in error correction is required to produce a perfect picture.
The general accepted figure for the ideal signal strength (metering varies with individual box models) is reckoned to be about 60%. This avoids problems with sensitive tuners not bein able to cope with high signal levels, where clipping the peaks of the analogue carrier can produce distortion of the output signal. In this case high levels of signal actually look low, down to the distortion produced by the signal clipping.
I can’t explain it then, as with and without the splitter my notes show that my signal quality was 100%.
All I do know is that when I used the splitter, I had a score of unwatchable and failed recordings in a week.
Since I removed the splitter and looped through to the TV I have had none in 3 months.
I had a similar situation with the splitter feed to the TV only a few weeks ago, in fact I posted on here about it, kept getting signal drop out or freezing. It turned out to be a cheapo RF lead which was the culprit. Funny thing was it only happened on certain muxes. Changed the lead and it solved the problem. Just shows how little things can really mess things up.
Been there, done that. I’ve changed the RF lead more than once and had had the aerial direction checked but nothing that solves the mystery so far.
Humax still can’t explain why the 9300T works perfectly whilst the 4000T keeps failing.
In the discussion on aerial connections I realized that my aerial had a VHF/UHF combiner and splitter. It seemed prudent to remove this and get a pure UHF signal. In doing so, I found that one of the Co-Axial plugs was broken on the splitter. (I blame the cat.) This has now been repaired and the two recordings I have made, so far, are OK. I will in future only use metal fittings. It looks like the plastic ones are too easily damaged.
- You must be logged in to reply to this topic.