[mythtv-users] HDHomerun tuner

[Gary Buhrmaster]

On Thu, Nov 21, 2013 at 5:31 PM, Monkey Pet <monkeypet at gmail.com> wrote:
> Hi all, I switched over to OTA.  I seem to be getting signal/reception to
> all my TVs.  However, my HDHomerun device doesn't seem to record some
> channels and some recordings have artifacts, eventhough the same channel is
> crystal clear on a TV.  I am wondering if other HDHomerun users are seeing
> issues with their tuners AND more importantly what did you do to fix the
> issue?  I have an antenna connected to a amplified splitter which
> distributes the signal throughout my house.  I have one of the 1st
> generation HDHomerun tuners, the white one with two inputs.  I also wonder
> if they fixed the tuner in later versions.

The tuner in the 1st gen HDHRs was known to not be as
sensitive(*) as those in some TV's(**).  The current gen is
considered to be somewhat better.  However, TV's are
still often better.  The next gen are supposedly better
still.  As with all such statements, you mileage will
vary (and any forward looking statements are protected
under the usual disclaimers :-).

You may want to check the signal information reported
while you are tuned to one of the problematic channels.
It is also possible that your amplifier is over-driving the
HDHR.  If the signal is consistently low, you may simply
need to boost the signal.  If the level varies (widely)
over time, you may be seeing multipath issues.

However, the other possibility is that your power supply
is going bad.  The HDHRs are known to have power
supplies that go bad, and the results can include poor
tuning lock, and poor signal decoding, and sometimes
random issues.  If you have another PS of the appropriate
voltage, size of plug, and polarity of plug, try that first.

The "fix", obviously depends on the exact root cause.

Gary

(*) Where "sensitive" can also include details like
the ability to deal with multipath issues.

(**) From an engineering perspective, there are
always trade-offs in design of the tuner/demodulator,
especially one that is intended to be able to tune
both CATV (targeted to be ~0 dBmV) and antenna
(often around ~-40 dBmV) levels.