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WattoToydarian

Post subject: DVB-T Channel Lock Issue

Posted: Wed Sep 13, 2006 1:16 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

I'm having a LOT of trouble getting my channels to lock. In .18 I had no trouble and it seems they might have broken it in .19 and still haven't fixed it yet.
My mythbackend.log shows this repeating over and over again:

Code:

2006-09-13 13:34:54.653 Could not find channel 5_1 in TVCT
2006-09-13 13:34:54.657 
VCT Terra: channels(4) tsid(0x68f) seclength(209)
Channel #0 name(KETC HD) 9-1 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(3) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(1)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #1 name(KETCKid) 9-2 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(4) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(2)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #2 name(KETC 9) 9-3 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(5) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(3)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #3 name(KETCDIY) 9-4 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(6) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(4)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)


2006-09-13 13:34:54.660 Could not find channel 5_1 in TVCT
2006-09-13 13:34:54.663 
VCT Terra: channels(4) tsid(0x68f) seclength(209)
Channel #0 name(KETC HD) 9-1 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(3) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(1)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #1 name(KETCKid) 9-2 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(4) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(2)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #2 name(KETC 9) 9-3 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(5) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(3)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Channel #3 name(KETCDIY) 9-4 mod(ATSC 8-VSB) cTSID(0x68f)
 pnum(6) ETM_loc(1) access_ctrl(0) hidden(0) hide_guide(1) service_type(2) source_id(4)
 descriptors length(17) count(1)
  Service Location Descriptor (0xa1) length(15)

Does anyone know what's causing this? Is it a problem with my cards, firmware, mythtv, what?
Thanks!

_________________
Backend: HP NetServer LT 6000r U3; 6 700Mhz Xeon CPUs; 3GB PC133 ECC; LSI Ultra160 SCSI 4 18GB 10kRPM striped system; 7200RPM 160GB recordings; Ubuntu-server 7.04; HDHomeRun box.
Frontend: A64 3000+; 512MB DDR; Hauppauge grey; knoppmyth PXE/NFS.

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tophee

Post subject:

Posted: Wed Sep 13, 2006 4:00 pm

Joined: Tue Sep 13, 2005 10:48 am

Posts: 852

Location: London, UK

I've just reinstalled R5D1 from scratch. I had a similar problem. I solved it by doing these things:

1. Enter the dvb-t directory : cd /usr/local/share/dvb/dvb-t/
2. Run dvbscan <Your Transmitter> ¦ tee channels.conf (though the tee channels bit didn't work for me)
2a. While the dvbscan is working make a note of hte first transmitter frequency.
3. (Or 2b.) make sure you locate the necessary information regarding this information (taken from parkinpants guide)

Quote:

I think that these values are always the same (for UK).

Bandwidth: 8MHz
Inversion: AUTO
Trans: 2K
Hierachy: none
Guard Interval: 1_32

The following values vary for each transport. Make sure you get these right or you might get 'choppy' viewing on certain channels. The first FEC value in the .conf file is the LP and the second FEC value is the HP.

Frequency: e.g. 7512666015
Constellation: e.g. QAM_16
LP: e.g. FEC_2_3
HP: e.g. FEC 1_2

And scan from mythtv-setup. If it doesn't pick everthing up, repeat the scan but make sure you set it to minimal update - otherwise you end up with several identical channels.

Hope this helps (typos and errors caused by tiredness!)
Good luck

_________________
Version:R8
Intel C2D 7400, Nvidia 5600 via HDMI to Samsung B37B650TW (PAL), Asus P5QL-E mobo, 4Gb PC6400 DDR2 ram, Samsung Spinpoint 500 Gb & 1Tb drive, Nova-HD-S2 (x2)

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WattoToydarian

Post subject:

Posted: Thu Sep 14, 2006 2:49 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

Thanks for the help tophee but I live in the US and theres no transmitter file for the US.
I just reformatted with R5D1 and the channel scan gave me all my channels on the first try but I still have a problem locking to one of my channels sometimes and antennaweb shows that it's closer than others.
Also, on step 3 of your guide, you dont say what I'm suppose to do with the info...

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WattoToydarian

Post subject:

Posted: Fri Sep 15, 2006 4:22 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

Well, it's been a while and i'm still having serious problems getting channels to lock. Sometimes no channels will lock!
Here is some output from mythbackend -v record trying to record a show but not.

Code:

2006-09-15 17:14:56.531 Recording starts soon, AUTO-Startup assumed
2006-09-15 17:14:56.541 TVRec(2): StartRecording(Legends of Jazz With Ramsey Lewis)
2006-09-15 17:14:56.541 TVRec(2): ClearFlags(AskAllowRecording,) -> RunMainLoop,
2006-09-15 17:14:56.706 TVRec(2): StartedRecording(0x82716b8) fn(/myth/tv//1091_20060915171500.mpg)
2006-09-15 17:14:56.708 TVRec(2): ClearFlags(CancelNextRecording,) -> RunMainLoop,
2006-09-15 17:14:56.708 TVRec(2): Changing from None to RecordingOnly
2006-09-15 17:14:56.708 TVRec(2): ClearFlags(FrontendReady,CancelNextRecording,) -> RunMainLoop,
2006-09-15 17:14:56.708 TVRec(2): SetFlags(AskAllowRecording,) -> RunMainLoop,AskAllowRecording,
2006-09-15 17:14:56.709 TVRec(2): Request: Program(yes) channel() input() flags(Recording,)
2006-09-15 17:14:56.711 TVRec(2): HW Tuner: 2->2
2006-09-15 17:14:56.711 TVRec(2): ClearFlags(PENDINGACTIONS,) -> RunMainLoop,AskAllowRecording,
2006-09-15 17:14:56.711 TVRec(2): Starting Signal Monitor
2006-09-15 17:14:56.711 TVRec(2): SetupSignalMonitor(1, 0)
2006-09-15 17:14:56.734 TVRec(2): Signal monitor successfully created
2006-09-15 17:14:56.734 TVRec(2): Setting up table monitoring.
2006-09-15 17:14:56.735 TVRec(2): ATSC channel: 9_1
2006-09-15 17:14:56.737 TVRec(2): Successfully set up ATSC table monitoring.
2006-09-15 17:14:56.738 TVRec(2): SetFlags(SignalMonitorRunning,) -> RunMainLoop,AskAllowRecording,SignalMonitorRunning,
2006-09-15 17:14:56.740 TVRec(2): ClearFlags(WaitingForSignal,) -> RunMainLoop,AskAllowRecording,SignalMonitorRunning,
2006-09-15 17:14:56.740 TVRec(2): SetFlags(WaitingForSignal,) -> RunMainLoop,AskAllowRecording,WaitingForSignal,SignalMonitorRunning,
2006-09-15 17:14:56.740 TVRec(2): ClearFlags(NeedToStartRecorder,) -> RunMainLoop,AskAllowRecording,WaitingForSignal,SignalMonitorRunning,
2006-09-15 17:14:56.740 TVRec(2): SetFlags(NeedToStartRecorder,) -> RunMainLoop,AskAllowRecording,WaitingForSignal,NeedToStartRecorder,SignalMonitorRunning,
2006-09-15 17:14:56.742 Started recording: Legends of Jazz With Ramsey Lewis "The Tenors": channel 1091 on cardid 2, sourceid 1
2006-09-15 17:15:42.882 MainServer::HandleAnnounce Monitor
2006-09-15 17:15:42.882 adding: PVR as a client (events: 0)
2006-09-15 17:15:43.224 Preview Error: Previewer file '/myth/tv/1091_20060915171500.mpg' is not valid.
2006-09-15 17:15:43.224 MainServer: Failed to make preview image.

and here is mythbackend -v channel

Code:

2006-09-15 17:18:01.861 Connected to database 'mythconverg' at host: localhost
2006-09-15 17:18:01.864 ChannelBase(1): Input #1: 'DVBInput' schan(9.1) sourceid(1) ccid(1)
2006-09-15 17:18:01.864 ChannelBase(1): Current Input #1: 'DVBInput'
2006-09-15 17:18:01.865 DVBChan(0): SetChannelByString(9.1):
2006-09-15 17:18:01.866 DVBChan(0): Frequency: 623000000 Modulation: QPSK
2006-09-15 17:18:01.867 DVBChan(0): Old Params: Frequency: 0 Modulation: QPSK
                        DVBChan(0): New Params: Frequency: 623000000 Modulation: QPSK
2006-09-15 17:18:01.867 DVBChan(0): Tune(): Tuning to 623000000Hz
2006-09-15 17:18:02.150 dvbchannel.cpp:wait_for_backend: Status: Signal,Carrier,FEC Stable,Sync,Lock,
2006-09-15 17:18:02.150 DVBChan(0): Tune(): Frequency tuning successful.
2006-09-15 17:18:02.151 DVBChan(0): SetChannelByString(9.1): Tuned to frequency.
2006-09-15 17:18:02.155 EITHelper: localtime offset -5:00:00
2006-09-15 17:18:02.157 DVBChan(1): Opening DVB channel
2006-09-15 17:18:02.159 ChannelBase(2): Input #2: 'DVBInput' schan(9.1) sourceid(1) ccid(2)
2006-09-15 17:18:02.160 ChannelBase(2): Current Input #2: 'DVBInput'
2006-09-15 17:18:02.160 DVBChan(1): SetChannelByString(9.1):
2006-09-15 17:18:02.161 DVBChan(1): Frequency: 623000000 Modulation: QPSK
2006-09-15 17:18:02.162 DVBChan(1): Old Params: Frequency: 0 Modulation: QPSK
                        DVBChan(1): New Params: Frequency: 623000000 Modulation: QPSK
2006-09-15 17:18:02.162 DVBChan(1): Tune(): Tuning to 623000000Hz
2006-09-15 17:18:02.169 dvbchannel.cpp:wait_for_backend: Status:
2006-09-15 17:18:02.169 DVBChan(1): Tune(): Frequency tuning successful.
2006-09-15 17:18:02.169 DVBChan(1): SetChannelByString(9.1): Tuned to frequency.
2006-09-15 17:18:02.171 New DB scheduler connection
2006-09-15 17:18:02.172 Connected to database 'mythconverg' at host: localhost
2006-09-15 17:18:02.175 Main::Starting HttpServer
2006-09-15 17:18:02.179 Main::Registering HttpStatus Extension
2006-09-15 17:18:02.184 mythbackend version: 0.20.20060828-3 www.mythtv.org
2006-09-15 17:18:02.185 Enabled verbose msgs:  important general channel
2006-09-15 17:18:02.185 AutoExpire: Found 2 recorders w/max rate of 277 MiB/min
2006-09-15 17:18:02.186 AutoExpire: Required Free Space: 3.2 GB w/freq: 5 min
2006-09-15 17:18:04.194 Reschedule requested for id -1.
2006-09-15 17:18:04.648 Scheduled 172 items in 0.5 = 0.03 match + 0.42 place
2006-09-15 17:18:04.651 Recording starts soon, AUTO-Startup assumed
2006-09-15 17:18:04.815 TVRec(2): Changing from None to RecordingOnly
2006-09-15 17:18:04.817 TVRec(2): HW Tuner: 2->2
2006-09-15 17:18:04.818 DVBChan(1): Opening DVB channel
2006-09-15 17:18:04.818 DVBChan(1): SetChannelByString(9.1):
2006-09-15 17:18:04.818 DVBChan(1): SetChannelByString(9.1): Already on channel
2006-09-15 17:18:04.818 DVBChan(1): Opening DVB channel
2006-09-15 17:18:04.840 SM(1)::AddFlags: Seen() Match() Wait(Sig,SNR,BER,UB,)
2006-09-15 17:18:04.840 DVBSM(1)::constructor(): initial flags 0x7400000
2006-09-15 17:18:04.840 DTVSM(1)::SetChannel(9, 1):
2006-09-15 17:18:04.841 SM(1)::RemoveFlags: Seen(PAT,PMT,VCT,) Match(PAT,PMT,VCT,) Wait()
2006-09-15 17:18:04.841 SM(1)::AddFlags: Seen() Match() Wait(PAT,VCT,)
2006-09-15 17:18:04.842 SM(1)::AddFlags: Seen() Match() Wait(MGT,)
2006-09-15 17:18:04.843 SM(1)::Start: begin
2006-09-15 17:18:04.843 SM(1)::Start: end
2006-09-15 17:18:04.847 Started recording: Legends of Jazz With Ramsey Lewis "The Tenors": channel 1091 on cardid 2, sourceid 1

Is this something the mythtv developers are working on or does a ticket need to be created?

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tophee

Post subject:

Posted: Sat Sep 16, 2006 1:03 am

Joined: Tue Sep 13, 2005 10:48 am

Posts: 852

Location: London, UK

Could it be more mundane issue like a bad antenna? Dodgy connection from the wall? A splitter? Certainly on my mythbox if I don't give a good signal in, it balks and channels don't work. I also read somewhere that someone had a problem with a signal amplifier - if the signal was too strong, again myth would have a hissy fit and not tune.

_________________
Version:R8
Intel C2D 7400, Nvidia 5600 via HDMI to Samsung B37B650TW (PAL), Asus P5QL-E mobo, 4Gb PC6400 DDR2 ram, Samsung Spinpoint 500 Gb & 1Tb drive, Nova-HD-S2 (x2)

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WattoToydarian

Post subject:

Posted: Sat Sep 16, 2006 1:40 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

Thanks for the info tophee! I've got a Terk indoor HDTV antenna connected to a 24dB amp with 2 outputs each going to one of my DVB tuner cards. So if that's the problem then could I attach a splitter to each of the outputs and run the extra connections to analogue TVs to fix the channel locks? Or do I have to remove the amp?
Here is a link to the amp http://www.walmart.com/catalog/product. ... id=2625064

Code:

Current setup:
ant > amp > Air2PC
          > pcHD2000
Planed setup:
ant > amp > 2waysplit > Air2PC
          |           > TV set
          |
          > 2waysplit > pcHD2000
                      > TV set

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WattoToydarian

Post subject:

Posted: Sat Sep 16, 2006 4:23 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

I just spent over 2 hours trying different wiring combos and nothing had any effect. :cry:

Now I'm having problems getting one of the transponders to pickup in the scan and I tried scanning like 10 times from both cards. So I did a "mythtv-setup -v channel > scan" and here is the output.
Mythtv Scan
I noticed that on one of the channels it said locked for a second and passed it without adding a channel with the strength bar at 0 and I found the log line at that point with this time stamp "2006-09-16 16:53:11.575" but it just says "DVBSM(0)::UpdateValues: Signal Lost" and I don't know if that is the missing channel or just one thats hard to pick up.
If anyone has any solutions please let me know because my family is pulling their hair out trying to watch TV lol.

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tophee

Post subject:

Posted: Sat Sep 16, 2006 4:23 pm

Joined: Tue Sep 13, 2005 10:48 am

Posts: 852

Location: London, UK

If I were you, I'd remove the amp and try a single tuner first. See how that goes. Indoor antennas can be a bit rubbish ... sorry can't be more technical about that. My only real experiance is with a powered loop antenna my parents bought me which I still use for 'real' tv in the bedroom and that can be real fuzzy. Myth wouldn't go near it.
If that works on the single card/direct line in add the amp. If not, try the single line with amp. If good, add second card etc.
If not, invest in a decent fixed indoor (attic type) or roof ariel.

Btw, I am speculating. Try, see what happens.
tbh, I expect a properly aligned outdoor ariel will give best results.
Good luck
edit - Looks like we posted simultaniously. VIA chips/et problem (though I'm not aware of channel locking problems with that)

_________________
Version:R8
Intel C2D 7400, Nvidia 5600 via HDMI to Samsung B37B650TW (PAL), Asus P5QL-E mobo, 4Gb PC6400 DDR2 ram, Samsung Spinpoint 500 Gb & 1Tb drive, Nova-HD-S2 (x2)

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WattoToydarian

Post subject:

Posted: Sat Sep 16, 2006 4:28 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

Woah, i've never seen this happen before, you posted at exactly the same time I did!!! :shock:

Anyway, I tried connecting my antenna directly to one tuner and that transport still didn't show up. I wish I had another antenna to try it with but before .19 I didn't have this problem. I dont know maybe I should try to convince my dad to get this antenna? http://www.walmart.com/catalog/product. ... id=5000835
Thanks again for your help.

P.S. Sometimes when I reboot my knoppmyth box and watch live tv it goes to the Air2PC by default and I get no locks on any channels with 0 signal and then I switch to the pcHDTV-2000 and it locks. Then the Air2PC eventually locks after a while so i'm thinking that part of the problem might be the Air2PC :?:

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WattoToydarian

Post subject:

Posted: Sat Sep 16, 2006 4:35 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

tophee wrote:

edit - Looks like we posted simultaniously. VIA chips/et problem (though I'm not aware of channel locking problems with that)

What is the VIA chip/et problem?

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nigelpearson

Post subject:

Posted: Sun Sep 17, 2006 3:14 am

Joined: Wed Mar 03, 2004 7:43 pm

Posts: 748

Location: Sydney, Australia

WattoToydarian wrote:

Thanks for the help tophee but I live in the US and theres no transmitter file for the US.

We can fix that ;-)

From the look of your mythbackend.log, you are trying to receive ATSC (US digital TV) and not DVB (worldwide digital TV), so you want to try the files in /usr/local/share/dvb/scan/atsc

_________________
| Nigel Pearson, nigel.pearson.au@gmail.com
| "Things you own end up owning you" - Tyler, Fight Club

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entourage

Post subject:

Posted: Mon Sep 18, 2006 9:29 am

Joined: Fri May 20, 2005 9:34 am

Posts: 113

Watto-
Don't know if this is relevant, but this post by sjerome mentions a possible problem between the Air2PC Rev. 2 and the new R5D1.

http://mysettopbox.tv/phpBB2/viewtopic.php?t=11621

Again, I don't know if you're having problems with that tuner or the HD2000, but I found that quite curious that you both are using the same ATSC tuner.

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WattoToydarian

Post subject:

Posted: Mon Sep 18, 2006 2:30 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

nigelpearson wrote:

From the look of your mythbackend.log, you are trying to receive ATSC (US digital TV) and not DVB (worldwide digital TV), so you want to try the files in /usr/local/share/dvb/scan/atsc

THERE IT IS!

I was looking all over for that :!:

I did a dvbscan with that file, redirected the output to a channels.conf, then tried to import it in mythtv-setup and nothing showed up.
So I did a normal mythtv-scan and I finally managed to get all my channels to appear. Then I added 28615Hz to all of the transponders which is what my channels.conf showed and it actually seems to lock much better.
After that I also discovered that for the times it says no lock I can now just wait a few seconds and it will lock.
It's still not perfect like before but I can live with it now.

entourage wrote:

Don't know if this is relevant, but this post by sjerome mentions a possible problem between the Air2PC Rev. 2 and the new R5D1.

I was actually having this problem with R5C7 using .19 so I think this all started when I switched to .19.

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WattoToydarian

Post subject:

Posted: Wed Sep 20, 2006 2:41 pm

Joined: Thu Jun 16, 2005 2:37 pm

Posts: 116

Location: St. Louis MO.

I found a ticket on the mythtv trac for this issue and I added some details to it so they will hopefully work this out soon.
The ticket can be found here: http://svn.mythtv.org/trac/ticket/2350

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