Author Topic: Improving reception with the Hauppauge Nova T500  (Read 5209 times)

totallymaxed

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Improving reception with the Hauppauge Nova T500
« on: January 26, 2008, 09:33:55 am »
If your having problems getting good, stable reception with the Nova T500 try the following;

edit the file /etc/modprobe.d/options

and add the line below to it;

options dvb-usb-dib0700 force_lna_activation=1

This will turn on the T500's Low Noise Amplifier which may fix your problem.

If not I would suggest you an external TV aerial booster with a variable gain control and use that too amplify the signal... start at the minimum setting and gradually increase the gain until the picture is stable (we do that here in some installations). Having an apparently perfect signal on an STB does not always indicate that the signal is right for the T500 I'm afraid.

Andrew
« Last Edit: January 26, 2008, 09:58:10 am by totallymaxed »
Andy Herron,
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niz23

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Re: Improving reception with the Hauppauge Nova T500
« Reply #1 on: January 26, 2008, 07:42:50 pm »
totallymaxed.

If your having problems getting good, stable reception with the Nova T500 try the following;

edit the file /etc/modprobe.d/options

and add the line below to it;

options dvb-usb-dib0700 force_lna_activation=1

This will turn on the T500's Low Noise Amplifier which may fix your problem.

If not I would suggest you an external TV aerial booster with a variable gain control and use that too amplify the signal... start at the minimum setting and gradually increase the gain until the picture is stable (we do that here in some installations). Having an apparently perfect signal on an STB does not always indicate that the signal is right for the T500 I'm afraid.

Andrew


I´d like to propose that this setting is created by lmce setup if possible since the built-in antenna amplifier is good to have because the signal is split to to recievers different recievers on the pci card.

For you guys that that need an external antenna amplifier. Remember to attach it as close to the antenna as physically possible. Otherwise you will also amplify the noise generated throughout the cable and that will in many cases make the reception even worse even though the card will see a stronger signal, but with worse SNR (signal-to-noise) ratio.

As to comparing signal quality against an STB. I totally agree. My dreambox and nokia says 100% signal quality, but my nova 500 card say 57-63%. I wonder which reciever is right. I tend to beleive that the STB is more accurate since they in many cases have better reciever circuits.

/niz23

totallymaxed

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Re: Improving reception with the Hauppauge Nova T500
« Reply #2 on: January 27, 2008, 08:32:11 pm »
totallymaxed.

If your having problems getting good, stable reception with the Nova T500 try the following;

edit the file /etc/modprobe.d/options

and add the line below to it;

options dvb-usb-dib0700 force_lna_activation=1

This will turn on the T500's Low Noise Amplifier which may fix your problem.

If not I would suggest you an external TV aerial booster with a variable gain control and use that too amplify the signal... start at the minimum setting and gradually increase the gain until the picture is stable (we do that here in some installations). Having an apparently perfect signal on an STB does not always indicate that the signal is right for the T500 I'm afraid.

Andrew


I´d like to propose that this setting is created by lmce setup if possible since the built-in antenna amplifier is good to have because the signal is split to to recievers different recievers on the pci card.

For you guys that that need an external antenna amplifier. Remember to attach it as close to the antenna as physically possible. Otherwise you will also amplify the noise generated throughout the cable and that will in many cases make the reception even worse even though the card will see a stronger signal, but with worse SNR (signal-to-noise) ratio.

As to comparing signal quality against an STB. I totally agree. My dreambox and nokia says 100% signal quality, but my nova 500 card say 57-63%. I wonder which reciever is right. I tend to beleive that the STB is more accurate since they in many cases have better reciever circuits.

/niz23


These LNA settings will be auto set for you in the next release of 0710... however for now you can make these changes manually ;-)

As to signal quality measured by STB's and DVB cards... its not always easy to compare what they are actually measuring in reality. However it seems to be the general case that STB's seem to have slightly more sensitive receivers... even though in many cases they may use the same chips!
Andy Herron,
CHT Ltd

For Dianemo/LinuxMCE consulting advice;
@herron on Twitter, totallymaxed+inquiries@gmail.com via email or PM me here.

Get Dianemo-Rpi2 ARM Licenses http://forum.linuxmce.org/index.php?topic=14026.0

Get RaspSqueeze-CEC or Raspbmc-CEC for Dianemo/LinuxMCE: http://wp.me/P4KgIc-5P

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colinjones

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Re: Improving reception with the Hauppauge Nova T500
« Reply #3 on: January 27, 2008, 10:21:10 pm »
I understand that totallymaxed's team find these cards ideal and that they work well. However, I would just like to put up a note of caution from my experience and consequent browsing of other forums, so that everyone can compare and know what to expect - actually this is probably more general that just the Nova t 500, but these are specific comments about that card, that I found.

There seems to be a lot of commentary about the inputs not being very sensitive even compared with equivalent cards, and even inconsistencies between the 2 tuners, and how the LNA works, and firmware:

http://www.xpmediacentre.com.au/community/tuners-vista/22841-nova-t-500-no-7hd-7sd-help.html

http://www.linuxtv.org/pipermail/linux-dvb/2007-August/019585.html

totallymaxed

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Re: Improving reception with the Hauppauge Nova T500
« Reply #4 on: January 28, 2008, 12:11:13 am »
I understand that totallymaxed's team find these cards ideal and that they work well. However, I would just like to put up a note of caution from my experience and consequent browsing of other forums, so that everyone can compare and know what to expect - actually this is probably more general that just the Nova t 500, but these are specific comments about that card, that I found.

There seems to be a lot of commentary about the inputs not being very sensitive even compared with equivalent cards, and even inconsistencies between the 2 tuners, and how the LNA works, and firmware:

http://www.xpmediacentre.com.au/community/tuners-vista/22841-nova-t-500-no-7hd-7sd-help.html

http://www.linuxtv.org/pipermail/linux-dvb/2007-August/019585.html

Well always use a variable gain signal amplifier with our Cores and I can honestly say we have few if any problems with the T500. I would suggest using one as a test.

By the way many of our Cores are tuned to the London Crystal Palace transmitter mentioned in the second thread in your earlier post. We dont see the problems mentioned at all.
Andy Herron,
CHT Ltd

For Dianemo/LinuxMCE consulting advice;
@herron on Twitter, totallymaxed+inquiries@gmail.com via email or PM me here.

Get Dianemo-Rpi2 ARM Licenses http://forum.linuxmce.org/index.php?topic=14026.0

Get RaspSqueeze-CEC or Raspbmc-CEC for Dianemo/LinuxMCE: http://wp.me/P4KgIc-5P

Facebook: https://www.facebook.com/pages/Dianemo-Home-Automation/226019387454465

http://www.dianemo.co.uk

colinjones

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Re: Improving reception with the Hauppauge Nova T500
« Reply #5 on: January 28, 2008, 02:51:23 am »
Andrew - I noticed that mention of Crystal Palace and recalled you mentioning it in the past, which is why I included it here.

Yep, will have to find a signal booster... now to find one! Haven't used one in years...

niz23

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Re: Improving reception with the Hauppauge Nova T500
« Reply #6 on: January 28, 2008, 12:51:29 pm »
totallymaxed.

If your having problems getting good, stable reception with the Nova T500 try the following;

edit the file /etc/modprobe.d/options

and add the line below to it;

options dvb-usb-dib0700 force_lna_activation=1

This will turn on the T500's Low Noise Amplifier which may fix your problem.

If not I would suggest you an external TV aerial booster with a variable gain control and use that too amplify the signal... start at the minimum setting and gradually increase the gain until the picture is stable (we do that here in some installations). Having an apparently perfect signal on an STB does not always indicate that the signal is right for the T500 I'm afraid.

Andrew


I´d like to propose that this setting is created by lmce setup if possible since the built-in antenna amplifier is good to have because the signal is split to to recievers different recievers on the pci card.

For you guys that that need an external antenna amplifier. Remember to attach it as close to the antenna as physically possible. Otherwise you will also amplify the noise generated throughout the cable and that will in many cases make the reception even worse even though the card will see a stronger signal, but with worse SNR (signal-to-noise) ratio.

As to comparing signal quality against an STB. I totally agree. My dreambox and nokia says 100% signal quality, but my nova 500 card say 57-63%. I wonder which reciever is right. I tend to beleive that the STB is more accurate since they in many cases have better reciever circuits.

/niz23


These LNA settings will be auto set for you in the next release of 0710... however for now you can make these changes manually ;-)

As to signal quality measured by STB's and DVB cards... its not always easy to compare what they are actually measuring in reality. However it seems to be the general case that STB's seem to have slightly more sensitive receivers... even though in many cases they may use the same chips!



Finally got VDR working as I want.
During the night I left vdr running to see if the livetv is stable.
This morning it was freezed and in my log I have these usb disconnect entries that are common with this card. (at least was common, see google)

dmesg give me this:
[ 6817.851046] usb 3-1: USB disconnect, address 2
[ 6817.853118] mt2060 I2C write failed
[ 6826.979740] dvb-usb: error while stopping stream.

In /var/log/messages:
Jan 28 11:21:51 dcerouter vdr: [13770] cleaning up schedules data
Jan 28 11:31:48 dcerouter kernel: [ 6817.851046] usb 3-1: USB disconnect, address 2
Jan 28 11:31:48 dcerouter kernel: [ 6817.853118] mt2060 I2C write failed
Jan 28 11:56:15 dcerouter -- MARK --
Jan 28 12:16:15 dcerouter -- MARK --
Jan 28 12:21:52 dcerouter vdr: [13770] cleaning up schedules data

Since I have had this card running for more than 3 weeks continously recording and with mythbuntu0710 without any problems I believe the problem might be the firmware shipped with lmce 0710 beta 3. The one shipped beta 3, dvb-usb-dib0700-01.fw is is replaced with dvb-usb-0700-1.10.fw which is the version I used with mythbuntu.

I will do the same test tonight with the new firmware and see if the problem is still there.
Will let you know.

To make the firmware working copy it over the old one ore make a symbolic link with the old name pointing to the new firmware file.
Otherwise the firmware will probably not be detected on boot since only the later V4L versions recognize the 1.10 firemware.

Version 1.10 if the firmware can be found here:
http://www.wi-bw.tfh-wildau.de/~pboettch/home/linux-dvb-firmware/dvb-usb-dib0700-1.10.fw

More info about this particular card,
http://linuxtv.org/wiki/index.php/Hauppauge_WinTV-NOVA-T-500


/niz23

niz23

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Re: Improving reception with the Hauppauge Nova T500
« Reply #7 on: January 29, 2008, 09:57:34 am »
Done some testing tonight and version 1.10 of the Nova 500 firmware seem to be lot more stable.
No more usb disconnect errors.

I propose that we include this version in 0710 instead. What u think?
Still get these,
[32175.690752] usb usb4: Controller not stopped yet!
[32565.843305] usb usb4: Controller not stopped yet!

Don´t know if they a errors. Have not seen these entries when using mythtv.

/niz23