On Wed, 20 May 2009, Thierry Lelegard wrote:
2) Since the TD-500 contains two aerial inputs instead of one for the T-500, I plugged in two antenna cables. Then, after some tests, I realized that this was a source of trouble: - Two antenna cables => lots of errors (mostly garbage sometimes, depending on the frequency). - Top input only => still many errors but much better on both tuners. - Bottom input only => got nothing on both tuners.
Normally there is a RF switch + loop through to be controlled when switching between diversity (not supported in Linux) and dual-input - so that you can connect only one antenna but still doing the dual reception.
If this switch is not handled correctly, I could imagine that the second input connected is "receiving" spurious signals and disturbing the first input, but there can be a lot of other reason as well.
If I understand the code correctly, this switch (if it is really there :) ) is not handled correctly. I don't know the TD 500 card, so maybe the Hauppauge guys can help on that. (Basically the question is, which GPIO is to be toggled)
3) There are still many uncorrectable errors (TS packets with "transport error indicator" set) in the input. The amount of uncorrectable errors is approximately 0.1% (depending on the frequency), while I do not have any with the T-500 using the same antenna.
When you tune both frontends at the same time, please try to not tune the same frequency.
These errors occurs in groups of +/- 50 consecutive packets with TEI set. Sometimes, in the middle of packets with errors, one packet has TEI clear but it is still erroneous (invalid PID in this context for instance). Note: I forgot to mention in the initial post that I set the following option: options dvb_usb_dib0700 force_lna_activation=1
This option has no effect on the TD 500. Though, if there is an LNA, it could be handled usefully.
regards, Patrick. -- Mail: patrick.boettc...@desy.de WWW: http://www.wi-bw.tfh-wildau.de/~pboettch/ -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html