[mythtv-users] Which Signal Strength/Quality Alternative is best?

[glen]

On Fri, 2017-01-20 at 14:56 -0600, Craig Huff wrote:
> On Fri, Jan 20, 2017 at 12:57 PM, Gary Buhrmaster <gary.buhrmaster at gm
> ail.com> wrote:
> > A couple of quick thoughts:
> > 
> > 
> > 
> > First, be aware that no consumer device is calibrated,
> > 
> > so the readings are perhaps "in the ballpark", but not
> > 
> > accurate.  If you want accurate readings, you need to
> > 
> > use a (calibrated) meter.
> > 
> > 
> > 
> > As I recall, the specifications require the devices to
> > 
> > support roughly -12 to +15 dBmV ("ideal" is 0dBmV),
> > 
> > and to decode 256QAM at a CNR of at least 33
> > 
> > (there is no limit, but in practice you do not see
> > 
> > numbers more than around low 40's except in
> > 
> > very tight plants).
> > 
> > 
> > 
> > It is *strongly* recommended in practice to avoid
> > 
> > being near the edge ranges of any of those numbers
> > 
> > because real world plants have some variance
> > 
> > (a few dBmV changes across the year is not unheard
> > 
> > of).  And since you are using consumer equipment to
> > 
> > measure, it is even more important to stay well
> > 
> > within the middle of the ranges.
> > 
> > 
> > 
> > A high quality amp, and/or a high quality splitter
> > 
> > (with appropriate cabling and connectors) should
> > 
> > really not be introducing ~2dB SNR noise. And a
> > 
> > high quality splitter is usually closer to -3.5dB
> > 
> > than a 4.7dB loss.  Whether is is an artifact of the
> > 
> > measurement or the splitter/amp/cables is unknown.
> > 
> > Something feels wrong there.
>  
> Gary,
> 
> My EE experience hasn't been near RF in decades, so it's all rusty,
> but yeah I agree with all you had to say.  I just don't have anything
> better than the data the Ceton provides.  I guess I'll try the
> splitter for now and maybe see if one from a Comcast customer service
> office is any better.
> 
> Most welcome would be the suggestion of a suitable amplifier (with or
> without a splitter incorporated) to use in place of the dinosaur that
> came from Radio Shack a couple of decades ago. Brand? Model? Vendor?
> 
> --
> Craig.
> 
> 
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my knowledge is not much in this area, but having used a few different
signal amplifiers, i get the best result with this:

http://www.3starinc.com/aska_am-125_uhf_vhf_fm_22db_distribution_home_a
mplifier.html

but i am using it for ota with 2 hdhomerun tuners and it is way better
than the radio shack and channel master ones i used before. 
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