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I have a Humax HDR-2000T connected to a fairly old Pioneer TV. A coax cable connects the Humax to a wide-band roof mounted aerial and is looped into the aerial port on the TV via the antenna connections. The aerial cable that comes from the external aerial is connected to a Maxview masthead amplifier MHA26U and in turn, connected to a Signal Booster, SLx TV Amplifier Four Output 27820BMR. The Humax is running software UKTFAC1.01.18 – I have tired to check whether updated software is available, but the Humax never seems to establish a connection, even though the internet connection appears to be established and working (the Humax TV Portal doesn’t work either). I have tried to disconnect the booster and MHA, but this results in a lack of signal message on all TVs connected to this setup.
We have recently had our external aerial repositioned after it rotated in high winds. It is now pointing, (as others are locally), toward Bristol Illchester Crescent transmitter. The Humax has been retuned.
My issue is the poor reception of some, non-DTV channels, particularly ITV3, More4, Dave, and E4. This intermittent reception drop affects recordings with some failing altogether or the pictures of each one breaking up. I have checked the strength and quality of the most problematic channels and they (sometimes) show 75%, 75% for each. Unfortunately, this issue is not constant and the signal strengths appears to fluctuate. For example, last evening it was so bad that we couldn’t watch the non-BBC channels, but this morning they seem to have recovered.
In order to narrow down the issue, I have disconnected the Humax from the aerial cable and plugged this directly into the TV and when viewing channels solely via the TV have not noticed any signal loss or break-up. Other TVs in the house that are not provided with a Humax work flawlessly – these are connected to the same aerial, aerial cable and boosters.
This indicates to me that the fault might lie with the internal tuners in the Humax. Would this be a sensible conclusion? Your advice would be much appreciated.
Many thanks. Chris
Try removing the amplifier and connecting the aerial directly to the Humax box using a coax coupler. The box may have a more sensitive tuner than the TV and the level is high enough to cause signal clipping.
chickenlegs – 4 hours ago »
We have recently had our external aerial repositioned after it rotated in high winds. It is now pointing, (as others are locally), toward Bristol Illchester Crescent transmitter. The Humax has been retuned.
How did you do the retune? Have you checked that the Humax is receiving on the correct set of multiplex channels? If in doubt try a manual tune using the instructions at https://myhumax.org/forum/topic/transmitters#post-2336
chickenlegs – 4 hours ago » My issue is the poor reception of some, non-DTV channels, particularly ITV3, More4, Dave, and E4.
Just to clarify a point, DTV is an abbreviation for Digital TeleVision. All Freeview TV transmissions are now digital. So there are no non-DTV channels.
(But we know what you mean. Probably what could be considered by some as non-mainstream channels)
Quote:How did you do the retune? Have you checked that the Humax is receiving on the correct set of multiplex channels?Well I did a full Auto tune as I was not confident in doing a manual one, but now I see the instructions, I will give it a go. Thank you for the linked instructions.
Whilst looking at the methodology, I checked my local transmitter (I am confident in it being the right one as this has been confirmed by a couple of electrical and tv engineers), and wrote down the channel numbers listed on the digitaluk.co.uk web site. I then went through each one as if I was doing a manual tune. There appear to be TV services within each of the multiplexes (BBC A, D3&4, SDN, ARQA and ARQB, except number BBC B (Ch 47). This one doesn’t appear to have any service information associated with it. I will try and complete the manual tuning instructions and see if this helps. Many thanks for your helpful replies.
grahamlthompson – 4 hours ago »
The box may have a more sensitive tuner than the TV and the level is high enough to cause signal clipping.
I wouldn’t have thought the quoted 75% signal strength was too high?
chickenlegs – 7 mins ago »
Quote:How did you do the retune? Have you checked that the Humax is receiving on the correct set of multiplex channels?Well I did a full Auto tune as I was not confident in doing a manual one, but now I see the instructions, I will give it a go. Thank you for the linked instructions.
Whilst looking at the methodology, I checked my local transmitter (I am confident in it being the right one as this has been confirmed by a couple of electrical and tv engineers), and wrote down the channel numbers listed on the digitaluk.co.uk web site. I then went through each one as if I was doing a manual tune. There appear to be TV services within each of the multiplexes (BBC A, D3&4, SDN, ARQA and ARQB, except number BBC B (Ch 47). This one doesn’t appear to have any service information associated with it. I will try and complete the manual tuning instructions and see if this helps. Many thanks for your helpful replies.
Without knowing which transmitter there is no way of telling which transmitter uses UHF for which MUX.
Adjacent transmitters (apart from a few using SFN’s (single frequency networks) have to use different Mux frequencies to avoid co channel interference)
Enter your postcode here and your house number here and tick the detailed view to give us a chance to at least help, I still reckon you have over amplified the source transmitter.
http://www.digitaluk.co.uk/operations/about_the_coverage_checker
Also add the direction tour aerial points and if the elements are vertically or horizontally aligned. In general (but not always) main power transmitters are horizontal and relays vertical (to avoid as far as possible interference).
Where I live most use Sutton Coldfield (vertical) which a wood to the the North precludes the much more powerful transmitter while the clear view to the south allows a a loft aerial to deliver stable pictures from the Lark Stoke relay.
I have seen some new local aerials erected by so called professionals pointed at Lark Stoke that are are horizontally mounted. They are losing a very large percentage of the available signal. Clearly they employed idiots posing as professionals.
http://www.digitaluk.co.uk/operations/about_the_coverage_checker
Why have you ignored my suggestion to check if you have too high a signal ?.
Pulling out two cables at the amplifier and connecting them together would immediately cofirm if the signal is simply too high.
Your local transmitter (if we knew which one would help) may have changed the frequencies used for it’s MUX and your existing group aerial may not now cover the frequency range required.
Look at aerial gain curves here.
https://www.aerialsandtv.com/atvstockaerialtests.html
If your transmitter was originally a group A transmitter and has now moved some MUX out of Group A you will likely need a new aerial ( London’s Crystal Palace is a recent example).
It’s all down to the government moving TV channels out of the 700MHz band to release the spectrum for mobile devices.
Post 1 says Bristol Illchester Crescent transmitter.
Re Ch 47, don’t forget that you usually have to select DVB-T2 for the HD Mux when tuning manually.
Thank you A1944 for your prompt. I will take note.
Thank you grahamlthompson for your detailed response. I am confident that the local (relay station) transmitter is Bristol Ilchester Crescent – this hasn’t changed in the time we have lived here. The polarity on the aerial is also correct and not changed in 20 years. I haven’t “ignored” your suggestion to check the signal strength. There are a few logistical things I need to do before I can due to the set up here; get into the loft, purchase a length of coax and a few connectors etc. As described earlier, I have been part way through the manual tuning process by looking at the digital.co.uk web site, but I will complete this once I have investigated the signal strength suggestion but I can’t do this at the moment.
I’ll let you know how I get on.
chickenlegs – 8 mins ago »
Thank you A1944 for your prompt. I will take note.
Thank you grahamlthompson for your detailed response. I am confident that the local (relay station) transmitter is Bristol Ilchester Crescent – this hasn’t changed in the time we have lived here. The polarity on the aerial is also correct and not changed in 20 years. I haven’t “ignored” your suggestion to check the signal strength. There are a few logistical things I need to do before I can due to the set up here; get into the loft, purchase a length of coax and a few connectors etc. As described earlier, I have been part way through the manual tuning process by looking at the digital.co.uk web site, but I will complete this once I have investigated the signal strength suggestion but I can’t do this at the moment.
I’ll let you know how I get on.
From the DTG reception predictor
Bristol Ilchester Crescent. All mux DVB-T except where noted
BBC A 41
D3&4 44
BBC B 47 DVB-T2
SDN 42
ARQA 45
ARQ B 39.
To remove the amplifier you just need a coax coupler. Remove the aerial in and the output to the Humax box and use the coupler to connect the two cables.
https://www.screwfix.com/p/labgear-plastic-coax-couplers-pack-of-10/26904#_=p
Hello again. So I have managed to detach the external aerial cable from all boosting device (including the masthead amplifier (MHA) and divert this directly to the Humax. These are my findings by investigating the MUX channels under the manual tune page, and in the bottom right hand corner of the ‘info’ area in the Humax for a selection of programmes:
Test 1
Ch41+ 73% signal (S), 100% quality (Q), Ch44 73% S, 100% Q, Ch47 (DVBT 2) 79% S, 100% Q, Ch42+ 70% S, 100% Q, Ch45 71% S 100% Q, Ch39 72% S, 100% Q.
The programmes themselves tell a different story however:
BBC1, 2, 4 plus all HD programmes – 50% S, 100% Q (by estimating how far the indicator icon is along the bar)
ITV, ITV2, 3 and 4, plus E4 – “…signal is too weak” message and no picture or sound.
Channel 4 and 5 – “…signal is too weak” message and no picture or sound.
Channel 4 HD and ITV HD – 50% S, 100% Q. I haven’t checked every channel as life’s too short!
Test 2
I have made the same direct connection of external aerial to a Sony TV that is equipped with an internal Freeview tuner and ALL programmes are working including the ones that fail to work via the Humax. The TV doesn’t have a method of checking signal strength or quality.
A few questions follow:
1. Does this indicate in itself that the tuners in the Humax are faulty given that the Sony tv works perfectly well under the same set up?
2. What does 100% quality actually mean, given that the received, ‘unboosted’ signal strength falls below the recommended limit in the Humax instructions?
3. Is it significant that the HD channels seem to work (and appear sharper) so much better than the non-HD channels?
As a comparison, when the external aerial cable is connected to my MHA and booster/ splitter and then on to the Humax, I get 100% S and 100% Q when looking at the MUX channel manual tuning page, good news you might think, but lower signal and quality figures in each ‘info’ area for individual programmes. The ITV, Channel 4, 5 and E4 programmes for example show (on average) 75% S and 75% Q.
Thank you for any suggestions you might have. Chris
chickenlegs – 8 mins ago »
Hello again. So I have managed to detach the external aerial cable from all boosting device (including the masthead amplifier (MHA) and divert this directly to the Humax. These are my findings by investigating the MUX channels under the manual tune page, and in the bottom right hand corner of the ‘info’ area in the Humax for a selection of programmes:
Test 1
Ch41+ 73% signal (S), 100% quality (Q), Ch44 73% S, 100% Q, Ch47 (DVBT 2) 79% S, 100% Q, Ch42+ 70% S, 100% Q, Ch45 71% S 100% Q, Ch39 72% S, 100% Q.
The programmes themselves tell a different story however:
BBC1, 2, 4 plus all HD programmes – 50% S, 100% Q (by estimating how far the indicator icon is along the bar)
ITV, ITV2, 3 and 4, plus E4 – “…signal is too weak” message and no picture or sound.
Channel 4 and 5 – “…signal is too weak” message and no picture or sound.
Channel 4 HD and ITV HD – 50% S, 100% Q. I haven’t checked every channel as life’s too short!
Test 2
I have made the same direct connection of external aerial to a Sony TV that is equipped with an internal Freeview tuner and ALL programmes are working including the ones that fail to work via the Humax. The TV doesn’t have a method of checking signal strength or quality.
A few questions follow:
1. Does this indicate in itself that the tuners in the Humax are faulty given that the Sony tv works perfectly well under the same set up?
2. What does 100% quality actually mean, given that the received, ‘unboosted’ signal strength falls below the recommended limit in the Humax instructions?
3. Is it significant that the HD channels seem to work (and appear sharper) so much better than the non-HD channels?
As a comparison, when the external aerial cable is connected to my MHA and booster/ splitter and then on to the Humax, I get 100% S and 100% Q when looking at the MUX channel manual tuning page, good news you might think, but lower signal and quality figures in each ‘info’ area for individual programmes. The ITV, Channel 4, 5 and E4 programmes for example show (on average) 75% S and 75% Q.
Thank you for any suggestions you might have. Chris
You might have mentioned you have two amplifiers in series. If you removed the power to the masthead amp then it effectively stops the signal.
The corrrect way to do this using a masthead launch amp is to distribute the signal using passive splitters. Doing it your way you are adding a large amount of unwanted noise.
Without power to the masthead this means nothing. If the power supply for the masthead was in the feed to the TV it’s not surprising that the TV then works.
https://www.aerialsandtv.com/ampsandsplitters.html#AmplifierOrSplitter
You could try plugging in a variable attenuator on the Humax input.
Just to update you. I have just spoken to a very helpful person at Humax support who tried to replicate the issue on the same model that he has, he couldn’t and the conclusion that he drew was that the SID unit is “probably” faulty as the signal indicated in the manual tuning area should be consistent with the programme channel strength. He also suggested that I try and plug it in in someone else’s home to see if the signal strength problem continues there. Not sure I want to bother our neighbours with this!
“You might have mentioned you have two amplifiers in series.” I had mentioned this in my original post…”The aerial cable that comes from the external aerial is connected to a Maxview masthead amplifier MHA26U and in turn, connected to a Signal Booster, SLx TV Amplifier Four Output 27820BMR.”
I have not “removed the power to masthead amplifier” – In the test, I did not connect the Humax nor TV to it at all – I described this in my reply. The power supply was not “in the feed to the TV” the set up was exactly the same for both scenarios.
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