[mythtv-users] Best tuner? - now driver question

Jay Harbeston jharbestonus at gmail.com
Tue Jan 12 18:34:56 UTC 2021



> On Jan 12, 2021, at 11:53 AM, DaveD <mythtv at guiplot.com> wrote:
> 
> On 12/6/20 11:34 AM, DaveD wrote:
>> On 12/6/20 6:45 AM, Barry Martin wrote:
>>> ...
>>> Over a year ago created a new BackEnd using a Hauppauge 1609: quad tuner.  The old system used their 1600 and 2250.  Antenna untouched; the new tuner took care of 99% of my previous pixellation and dropout issues.
>>> 
>>> Antenna positioning, coax quality, and other hardware factors are also important, but the newer generation of tuners are better at compensating for signal strength variations due to wind.  FWIW I actually have two antenna systems here: both antennae are essentially identical (same model, purchased maybe six months apart).  One goes to the Backend. the other to the TVs.  Whole bunch of variables due to the distribution but some TVs are better able to display when it's windy, some are not. The older and cheaper TVs will break up while the newer and better TVs will have an essentially solid display.  And there have been times we've switched from OTA TV to Live TV via MythTV because of the poor signal.
>>> 
>>> So yes, the tuner makes as much difference as the antenna does.
>>> 
>>> Barry
>> 
>> The 1609 sounds perfect.  I googled it and Amazon has 3 sellers from $230 to $250, and the $230 is back-ordered, due in-stock Dec 15.  So I checked Hauppauge's site, and their store has if for $120.  This is odd.  Anyway, I ordered one as well as one of their dual USB sticks.  Hope this eliminates those dropouts.  Thanks for the info.
>> 
>> Dave D.
>> 
> I've been studying the performance of my new Hauppauge Quad vs the performance of my Old Dvico Fusion dual.  I wrote a GUI app using QT (my self-tutorial) that has a bar graph for signal strength and another for SNR.  They update every 100mS and it works great for watching signal strength while moving antennas. It's based on code from dvb-apps and uses channels.conf files generated with scandvb.  When invoked, it loads the channels from the .conf file and I can choose which channel I want to monitor. I can open as many instances as I want and monitor as many channels as I want (up to the number of adapters, which is now 6).  Monitoring multiple channels simultaneously while moving the antenna works GREAT.
> 
> With a -s command line argument, my app will successively monitor each of the channels in the file for 10 seconds and log the results, including the card used for tuning.  With other command line arguments, I can specify which card to use and which .conf file to use.  Using cron jobs, I've been logging signal strength and SNR statistics hourly for each of the cards for about 4 days.
> 
> Info was interesting:  some times on some channels the Dvico did better, other times/channels the Hauppauge did better.  Overall, though, they are very similar.  One of the parameters logged is how many of the samples have a lock.  100% lock for the full monitor time (also configurable) indicates a reliable recording. Anything less relates to varying degrees of pixelation.  My signals are mostly good, but some are very weather-dependent. When a low moves through with associated south wind, forget KOMO!
> 
> After a couple of days, I stopped checking the data and let it run for a week before looking again.  Unfortunately, after about 3 days the logged card started to always be "unknown".  That's the default.  When the program starts, it checks for adapters by listing /dev/dvb.  It then finds the chip for each adapter using "dmesg | grep 'DVB: registering adapter '" which lets me build a unique name for each card.  The problem occurred when dmesg got overloaded with messages and the old ones were dropped.  No more output from the dmesg | grep command.
> 
> Whenever I've used dmesg in the past, it showed history all the way back to the boot.  I never even realized there was a limit, but now the driver for the Hauppauge spams dmesg every time it changes channels with "xc5000: Firmware dvb-fe-xc5000-1.6.114.fw loaded and running" (ridiculous!).  With my app changing channels 12 times every hour (plus normal use), it takes about 4 days to fill the dmesg ring buffer.  The Dvico does a similar output to dmesg, but only once per app invocation.
> 
> Are there any experts on drivers on this list?  Is there a way I can silence these (somewhat) useless log entries?  I started to look into changing the source for the driver, but that got overwhelming pretty quick.  I know, now, that relying on dmesg will always, eventually break, but normally I end up rebooting every couple of weeks or so for other reasons.  I'd like to keep my logging working for more than a few days, and I can always just record the card ID with something that runs on boot, but it just bothers me that something spams my system logs this way. Suggestions appreciated.
> 


Have you looked into the HDHR5 2/4 tuner network boxes? They work well for me, and there are no driver problems with them, and they have worked well for me.


Just curious.

Regards


More information about the mythtv-users mailing list