ABM (UK-Terrestrail ): Add HD channels/regions REVISTED Bluebell Hill

[Huevos]

One of the problems I hit when investigating different tuners was that the different display features appear to use different data, and/or display the available data incorrectly. Using the logic I proposed for DVB-T frequency finder both Si2168 & Si2169 provide sensibly varying values. The Si2169 responds sensibly to the "signalQuality = self.frontend.readFrontendData(iFrontendInformatio n.snrValue)", but the Si2168 does not and so the "signalQuality = self.frontend.readFrontendData(iFrontendInformatio n.signalQualitydB) is invoked and gives values that appear to be in milliBels - i.e. 30 dB is reported as 3000.


The following SNRdB results from the webif "web/signal?AGC=" command may be of interest (the main figures are averages across 20 samples, and those in brackets are the lowest figures in those samples) :

   	      	               <----------------- Signal SNR -----------------> 
	Name	Status	Tuner A	        Tuner B	     Tuner C	     Tuner D
	    	       Si2169 	  Si2169 	 Si2169 	      Si2168 

1	PSB1	In Use	340 (334)	301 (301)	340 (340)	31 (31)	

2	PSB2	In Use	348 (347)	341 (340)	340 (334)	32 (31)	

3	PSB3	In Use	354 (353)	348 (347)	347 (308)	31 (31)	

4	COM4	In Use	360 (353)	358 (353)	360 (360)	33 (32)	

5	COM5	In Use	360 (360)	343 (340)	341 (340)	33 (33)	

6	COM6	In Use	355 (353)	284 (275)	301 (301)	28 (27)

Note that the "HD" mux is being shown apparently correctly, unlike Signal finder where I have seen the same problem as reported by ccs.

It would also appear that the Si2169 reports are in centiBels, as they seem to be a factor of 10 larger than for the Si2168. However as DVB-T frequency finder is only interested in relative levels, that would not affect the results.


EMJB

So we need to look at why Signal finder and OWI produce different outputs for AGC.

For me the values correspond 100%.

How are you testing this?

[Huevos]

I thought that the idea was that different chipsets produce different results (but could easily be wrong).
I have a box with 4-different DVB-T2 tuners in....

I don't understand your point. All tests are done on the same tuner and compared relatively.

[Huevos]

Even if a service is duplicated on Crystal Palace I don’t what a scan of CP frequencies which for me can be unreliable.

If you want to be in control of that you need to create your own file manually. No automatic process is going to know what transponder you want to prioritize and why.

[Huevos]

Selecting the first MUX it sees with a decent SNR or signal strength is a poor way of selecting the MUXs to scan.

The mux selected is the one with the best signal quality. If signal quality is maxed out on both transponders (possibly due to broken drivers) the transponder with the lower frequency is selected.

[Huevos]

I suspect (have no proof nor inclination at present to further investigate) there is something that prevents T2 scanning when only one entry for the transmitter in the terrestrial_uk_freeview.xml file hence the reason I added the 3 entries to my custom transponder section.

If you can't receive those muxes there is no need for custom transponders.

I have one entry in the .xml file for the MUX with BBC1 and a subsequent scan doesn't find any T2 MUXs

Which .xml file?

I check with a manual scan for a single Predefined Transponder (T2 MUX transmitter channel number). The "system" default is DVB-T and not DVB-T2 and I change it to Auto and check that the MUX is active and I get the expected T2 channels.

If I now go back to ABM and scan I think it now finds all the DVB T and all of the DVB T2 MUXs

This because what you have done is a pre-scan. That negates the need for a custom transponder.

It's maybe when installing a new image the system thinks the tuner configuration is DVB T irrespective of what it says in Tuner Config/Tuner Setup and hence the ABM scan only finding DVB T MUXs and it required going to somewhere else (such as manual scan) to toggle the setting to DVB T2 (or using the custom entry in the terrestrial_uk_freeview.xm to do the same).

ABM only requires a tuner to be enabled.

[ccs]

Something is seriously wrong with the arithmetic for that tuner. Someone needs to look at that.

CH 58 is not showing signal because the selected region does not correspond to your mast. If you switch into user defined mode you should be able to tune that mux.

… it's CH 28 - which is a valid mux, so there is still something odd happening.

[ccs]

"http://et10000/web/signal?AGC=" on your browser, changing the address as necessary of course.

Thanks, I guess there are lots of these gems hiding somewhere (I've never looked for them, mind.)

The command finds data for all mux's eg -

<e2frontendstatus>
  <e2snrdb>373.55 dB</e2snrdb> 
  <e2snr>100 %</e2snr> 
  <e2ber>0</e2ber> 
  <e2acg>0 %</e2acg> 
  </e2frontendstatus>

Signal finder only finds data for SD mux's, nothing comes up on the HD mux's.

[Huevos]

… it's CH 28 - which is a valid mux, so there is still something odd happening.

It was a typo.

[Huevos]

Signal finder only finds data for SD mux's, nothing comes up on the HD mux's.

Signalfinder will open that mux if you enter the correct parameters.

[ccs]

Signalfinder will open that mux if you enter the correct parameters.

If I start at ch 22, and move slowly thru to 60, only the valid sd mux's give any values.

Am I using incorrect parameters, there's only one that needs changing?

If I'm tuned to ch 28, bbc1 hd, signalfinder fires up on ch 28, with nothing showing.

[Huevos]

What I guess is happening is the values in terrestrial.xml don't correspond with your mast. In Signalfinder if you switch to user defined transponder and then to T2 it should show signal.

[ccs]

What I guess is happening is the values in terrestrial.xml don't correspond with your mast. In Signalfinder if you switch to user defined transponder and then to T2 it should show signal.

Yes - changing to T2 works.

SD channels work with user defined set to T or auto.

HD channels only work with T2.

[adm]

If I start at ch 22, and move slowly thru to 60, only the valid sd mux's give any values.

Am I using incorrect parameters, there's only one that needs changing?

If I'm tuned to ch 28, bbc1 hd, signalfinder fires up on ch 28, with nothing showing.

If you are performing this manually as part of a test and have left Menu-> tuner config -> manual scan -> Sytem =DVB-T then you will only pick up SD MUxs when you slowly select each transmitter channel. If you change that setting to Auto or DVB-T2 you should pick up both SD and HD MUXs with a test manual scan.

[EMJB]

I don't want to accept fixes for broken drivers. But I do appreciate your contribution.

My suspicion is that it is frontend.cpp that is the problem, rather than the drivers, and it has a lot of tuner-specific code, but nothing for the Si2168/9. Who is likely to sort out what is wrong and fix it, and what sort of timescale is that going to take?

While I appreciate your position but:

• In the short term you will continue to waste time responding to users with problems that my code avoids (e.g. incorrect terrestrial_finder.xml files being reported).
• It does seem likely that new tuners will appear and suffer from the same problems, so you are in danger of creating work in the long term for yourself as problems keep arising.

It does seem to be pity to deny people with Si2168/9 tuners a working feature for what a suspect will be a significant time for the sake of a few lines of code that you could remove once the source of the problem has been fixed. N.B. I suspect the TerrestrialScan plug-in suffers from the same problems, so that is not a useful alternative as an interim measure for people with Si2168/9 tuners.

If you really are adamant not to include my fixes to get better data, I suggest the user advice along the lines of my warning message when data is missing, and a log of the tuner type in use, would be useful additions.


EMJB

[Huevos]

If you are performing this manually as part of a test and have left Menu-> tuner config -> manual scan -> Sytem =DVB-T then you will only pick up SD MUxs when you slowly select each transmitter channel. If you change that setting to Auto or DVB-T2 you should pick up both SD and HD MUXs with a test manual scan.

No, that is not correct. T2 should only select T2 muxes. T should only select T muxes. Auto should select either. Any diversion from this behaviour means the drivers are faulty.