• The forum software that supports hummy.tv has been upgraded to XenForo 2.1!

    This upgrade brings a number of improvements including the ability to bookmark posts to come back to later. Please bear with us as we continue to tweak things and open a new thread for any questions, issues or suggestions in Site/Forum Issues.

How bad is the BBC3/4 recording problem?

Black Hole

May contain traces of nut
As a UK DVB receiver would not expect to see a HiDef service on a DVB-T mux, maybe there is scope for some confusion somewhere?
 
OP
M

mightyoakbob

Member
Post a zipped copy of your tuning database and somebody may take a look. If you don't, then nobody can guess.
As I expect you can guess I have not the slightest idea where to look for the the tuning database.

However, I have posted screen shots showing the manual tuning of the two T1 modulators. If that isn't enough proof for you then you are basically saying I'm lying.
What does CS stand for in your world anyway?
Customer Services.
CF - sorry.
Why can't you quote actual version numbers of firnwares instead of meaningless terms like "the slow epg version".
HDR_FOX_T2_1.03.12_mod_3.13.zip
I think it is latest one, with the distinguising feature of a slow epg according to the website.

I hope that answers all the questions. I'm happy to post the tuning database if someone will tell me where I find but that is to help with diagnosis not to prove I'm not lying.

I see no point in getting further embroiled in pointless arguments like I should have said T and not T1. T1 has no possiblity of ambiguity even if it is not 100% the norm.


Bob.
 

Attachments

OP
M

mightyoakbob

Member
Well this seems to have wandered a bit!

I suspect that the OP was originally looking at

https://wiki.hummy.tv/wiki/Which_Version

which gives the pros and cons of the different available versions and still notes the BBC3/4 recording issue for the older underlying firmware versions.

I have no idea if this problem (zero-byte .nts files) still happens, does anyone else? There's no reason to think that it wouldn't since it required a firmware fix from Humax which is only in 1.03.xx. I run the latest version everywhere so wouldn't have seen this.


You can add a poll to this thread and let people vote, but of the devices that are registered with remote scheduling, 92.6% of them are using 1.03.xx, 6% are using 1.02.28+ and the remainder are on 1.02.20
Your suspicion is correct and thank you for the rest of the info.

Bob.
 

af123

Administrator
Staff member
@mightyoakbob - to get back on topic, I have no idea how prevalent the BBC3/4 HD recording issue is with older firmwares. Almost everyone here is using the 1.03.xx versions of the underlying Humax firmware.
However, at least the badnts package is available that can fix any such recordings automatically, and the sidecar package would allow you to reconstruct the sidecar files should you want trick play on them.
You might be able to live with the slower EPG by cleaning up the schedule/tuning database.
 
OP
M

mightyoakbob

Member
@mightyoakbob - to get back on topic, I have no idea how prevalent the BBC3/4 HD recording issue is with older firmwares. Almost everyone here is using the 1.03.xx versions of the underlying Humax firmware.
However, at least the badnts package is available that can fix any such recordings automatically, and the sidecar package would allow you to reconstruct the sidecar files should you want trick play on them.
You might be able to live with the slower EPG by cleaning up the schedule/tuning database.
Thank you.
Bob.
 

Trev

The Dumb One
Yep. Sure enough, my Technomate tunes as a T source (no sig str or Q when T2 tuning selected) but displays in the CF Tuned Multiplex Information as DVB-T2 (HD)
It did rather get its knickers in a knot over the fact that the video I/P to the mod was the T2 itself.
 

Black Hole

May contain traces of nut
Thanks for the confirmation, two independent observations of the same unexplained effect puts a very different complexion on matters. So, exactly what does the Mux Info diagnostic use to (unsuccessfully) distinguish DVB-T from DVB-T2 if it's not the decoder setting? If it is the decoder setting as picked up from the tuning database (why would it be anything else?), why does that not agree with the actual decoder setting?

Maybe (just maybe) there is no decoder setting in the database, and the decoder switches automatically (but if that were the case, I don't see why it would be necessary to select between DVB-T and DVB-T2 when tuning manually, or automatic tuning to go through a DVB-T cycle followed by a DVB-T2 cycle). The Mux Info would then be using other assumptions to decide, which produce an incorrect result for this modulator. But it seems unlikely the Mux Info diagnostic would bother to recreate information rather than simply provide a means to display the actual tuning database content (and nothing else). All this seems so unlikely I'm not even declaring it a hypothesis.

Anyone prepared (and able) to look into this in more depth is still hampered by lack of data! Despite prpr's request, so far nobody with a DVB modulator and able to demonstrate this effect has posted the necessary data.

This topic of discussion needs to be transferred to the CF section.

It did rather get its knickers in a knot over the fact that the video I/P to the mod was the T2 itself.
In what way? Why? The modulator should be receiving HDMI input from the HDR-FOX regardless, and the HDR-FOX should be receiving UHF input from the modulator regardless, so what negative effect did you see?
 
Last edited:

Trev

The Dumb One
The box automatically switched to the mod's LCN on completion of tuning it. The symptoms were 'chuntering/slow flickering' of the picture (best way I can explain it without a video), picture gradually acquiring a green hue, non/very slow response to remote control. Had to hold the power button for about 5 secs before it switched to S/B and then I quickly changed channels away from the mod LCN as it was booting.

The modulator should be receiving HDMI input from the HDR-FOX regardless, and the HDR-FOX should be receiving UHF input from the modulator regardless
Thus creating a feedback loop?
Post a zipped copy of your tuning database and somebody may take a look. If you don't, then nobody can guess.
Tell me how to do it then I will.
 
OP
M

mightyoakbob

Member
Thanks for the confirmation, two independent observations of the same unexplained effect puts a very different complexion on matters.
I take it you now believe me, despite me posting 3 images yesterday showing this feature the doubt remained.
Despite prpr's request, so far nobody with a DVB modulator and able to demonstrate this effect has posted the necessary data.
Why be helpful and tell people how to do what you want when it's much more fun to have another pop.
Okay.
Despite me saying I would post the data but I don't know where to get it from, nobody has told me how.

Tell me how or post a link to the instructions.

Bob.
 
OP
M

mightyoakbob

Member
Yep. Sure enough, my Technomate tunes as a T source (no sig str or Q when T2 tuning selected) but displays in the CF Tuned Multiplex Information as DVB-T2 (HD)
It did rather get its knickers in a knot over the fact that the video I/P to the mod was the T2 itself.
Thanks Trev.

Bob.
 

EEPhil

Number 28
So, exactly what does the Mux Info diagnostic use to (unsuccessfully) distinguish DVB-T from DVB-T2 if it's not the decoder setting?
Speaking from total ignorance of the Mux Info diagnostic - I offer the following observation.
If I understand it correctly the devices are multiplexing mpeg4 type streams onto a DVB-T mux. Could it be that Mux info is determining the mux type from the type of stream contained (crudely, mpeg4 or mpeg2). Therefore, if it sees mpeg4 it's DVB-T2 - even though it isn't. If that makes sense.
 

Black Hole

May contain traces of nut
Thus creating a feedback loop?
Not while in the process of tuning, no. While you are tuning, there is no feed-through of the video or audio - the HDMI output is just the tuning menu.

The symptoms were 'chuntering/slow flickering' of the picture (best way I can explain it without a video), picture gradually acquiring a green hue, non/very slow response to remote control.
Yeah, you would expect weird stuff if you encode the output of the video decoder and stick that into the decoder, but I thought you meant while you were tuning.

Tell me how to do it then I will.
There may be a way to access the relevant file via FTP or the WebIF diagnostics file browser, but you can definitely save it to USB via the hidden menu.

If I understand it correctly the devices are multiplexing mpeg4 type streams onto a DVB-T mux. Could it be that Mux info is determining the mux type from the type of stream contained (crudely, mpeg4 or mpeg2). Therefore, if it sees mpeg4 it's DVB-T2 - even though it isn't.
Quite, and this seems to be the only logical explanation... but as per my previous post: why would it? The nature of the encoding of an individual transport stream within the overall mux data stream is irrelevant to the demodulation of the overall data stream itself (which is where the distinction between DVB-T and DVB-T2 lies). Also, if the distinction is so crude and indefinitive as that, there is nothing to stop it getting the wrong answer for broadcast muxes.

The demodulator needs to know whether to demodulate as DVB-T or DVB-T2, so a flag needs to be in the tuning database, and if that's the case there is no reason for Mux Info to get it wrong! However, by the maxim "whatever remains must be the truth", there has to be something wrong with this chain of deduction.

Although this issue affects very few people, and has no significant consequences other than that it is an incorrect representation, it is a very big puzzle - and the reason I was so sceptical of the first vague report (with no supporting evidence presented).
 
Last edited:

EEPhil

Number 28
I shall take af123's reply as an indication that I'm talking rubbish! :D
(Although I'll have a good look through the information at the end of that link to see...)
 
OP
M

mightyoakbob

Member
Speaking from total ignorance of the Mux Info diagnostic - I offer the following observation.
If I understand it correctly the devices are multiplexing mpeg4 type streams onto a DVB-T mux. Could it be that Mux info is determining the mux type from the type of stream contained (crudely, mpeg4 or mpeg2). Therefore, if it sees mpeg4 it's DVB-T2 - even though it isn't. If that makes sense.
Sounds a perfectly reasonable hypothesis to me.
But it would be better if the algorithm used a more accurate criteria.
Bob.
 
OP
M

mightyoakbob

Member
There may be a way to access the relevant file via FTP or the WebIF diagnostics file browser, but you can definitely save it to USB via the hidden menu.
So now all I need to know is how to enter the hidden menu and I'm away, if you still want it of course.

Bob.
 

EEPhil

Number 28
Bingo!
eTransMode in the table is showing 2 for real DVB-T and 6 for DVB-T2. The two debatable muxes are showing 1 in the database.
Looks like the Humax is recognising the muxes as different and in its own software correctly interpreting this as DVB-T.
I wouldn't normally quote this source, but I can't find any other explanation quickly:
https://ukfree.tv/article/1107051920/Freeview_modes_a_simplified_explanation_ said:
There are 10 modes defined for use in the UK, these are:
  • Mode 1: DVB-T 1705 (2K) carriers, 64QAM mode, FEC=2/3, 1/32 guard = 24.13Mbps
  • Mode 2: DVB-T 1705 (2K) carriers, 16QAM mode, FEC=3/4, 1/32 guard = 18.1Mbps
  • ...
  • Mode 6: DVB-T2 27841 (32KE) carriers, 256QAM mode, FEC=2/3, 1/128 guard = 40.2Mbps
  • ...
 
Last edited:
Top