[mythtv-users] Hauppauge 1609 and Pixelation Tests

Stephen Worthington stephen_agent at jsw.gen.nz
Sat Jun 1 05:57:07 UTC 2019

On Fri, 31 May 2019 14:12:17 -0500, you wrote:

>Hi James!
>> My wife berates me for talking funny! My appologies.
>Wow! You get to speak?! <bseg>
>> I?ve tried lots of tuners, the worst of which was unwatchable on the worst channel on HD
>> Without changing anything in the signal path I?m now using the Haupague Win TV usb tuners.
>> I?ve not seen a single block or stripe since getting them.
>Ah! OK, that is what I thought you intended: with various tuners the 
>worst viewing was unwatchable on a weak/distant/incorrectly aimed station.
>“Everything” makes a difference: tuner, cable (coax), antenna. With the 
>TV tuners seems none list the sensitivity (µV), so pretty much have to 
>guess and reply on others’ experiences. (One reason why I posted my 
>follow-up which started this thread.)
>Use of good-quality cable (coax): RG-6/U vs. RB-59/U – even then there 
>are multiple options. Check your cable: I’ve had 
>commercially-manufactured extension pieces (~18” long) where the center 
>conductor slipped: was pushed during installation so one end barely 
>touched the splitter’s connector and the other end extended into the tuner.

And do not forget the joints - make sure they are screwed together

>Antenna aiming: where the studios are aren’t necessarily where the 
>transmitter site is. At my location (house) the studios are in various 
>surrounding cities west and south but all except one transmitter are at 
>an Antenna Farm 20 mile south-southeaast.
>You probably know all that, just a good review (especially that quirky 
>cable-slid one!)
>Most of the reception problem here seems to be external factors, 
>combined with tuner specs, I think similar to your issues. Calm wind, 
>good recordings. Windy conditions, start to get pixelation issues; seems 
>to be some correlation with the RF Channel (the actual frequency the TV 
>station is transmitting, not its virtual channel), though that tends to 
>fall apart as locally there are two stations, one RF36 and the other 
>RF38, both 1000KW, on literally the same tower. yet RF36 will pixelate 
>horribly and RF38 will be a clear picture.

Tuners and aerials have a centre frequency they operate best on, and
performance tends to fall off gradually the further away from the
centre frequency a transmitter is operating on.  So for two stations
on the same tower at the same power, the difference in frequency will
usually explain different reception on the same tuner.

>As for the Backend tuners, LIS previously the newer Hauppauge 1609 tuner 
>has worked well for me. Admittedly due to a little sloppiness in my 
>quickly connecting to an antenna the Backend with the 1609 inside is 
>connected to the antenna and splitter feeding the old Backend with the 
>1600 and 2250 tuners. IOW the two Backends are on the same antenna and 
>so getting the same signal. The new Backend (with 1609) is recording a 
>1000% better under mediocre reception conditions compared to the old 

So are you saying your 1609 tuner gets a direct feed from an aerial,
but the 1600 and 2250 tuners get a split feed?  If that is the case,
the 1600 and 2250 tuners will be getting a bit less than half the
signal level of the 1609, so you can not compare the performances that
way at all.

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