[mythtv-users] HDHR Intermittent Recording

Yeechang Lee ylee at pobox.com
Fri Jan 4 17:08:30 UTC 2008

James Oltman <cnlibmyth at gmail.com> says:
> All excellent questions that I should have known to give before I
> sent the first email.  OK.  I am running ATSC currently.  I'm only
> receiving one channel, and hence, I'm only recording one channel
> (local FOX affiliate).  The HDHR is connected to the backend via a
> secondary NIC dishing out DHCP on that interface.  The signal
> strength was near 100%.

Signal strength by itself is almost meaningless with ATSC. It's
unfortunate that mythfrontend only reports this number. Try this:

hdhomerun_config xxxxxxxx get /tuner0/debug (or /status)

Note three numbers:

     ss=0 snq=0 seq=0

ss = signal strength
snq = signal quality
seq = what percentage of the signal over the past second was clean

The key number is snq. In my experience, if snq is higher than 40 or
so, seq will stay at 100 all or most of the time. Higher is, of
course, better. ss matters only to the extent that a stronger signal
contributes to the higher snq, but a ss of 100 by itself guarantees
nothing whatsoever about the quality or usability of the signal.

So, try something like

    watch -n 1 hdhomerun_config xxxxxxxx get /tuner0/debug

then use mythfrontend to tune the channels (or channel, in your case)
you want to receive, then use snq to figure out the best antenna location and

And, yes, insufficiently-good reception absolutely can help to explain
the issues in your original message. mythbackend doesn't create the
recording file until the signal's locked in. No signal means no

Frontend/backend:	P4 3.0GHz, 1.5TB software RAID 5 array
Slave backend:		Quad-core Xeon 1.6GHz, 6.6TB sw RAID 6
Video inputs:		Four high-definition over FireWire/OTA
Accessories:		47" 1080p LCD, 5.1 digital, and MX-600

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