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Old 1-Sep-2020, 1:51 AM   #7
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Quote:
Originally Posted by verder
You asked in the thread about Tablo vs the TV tuner. I've only really used the TV tuner to do the original setup (finding the sweet spot.) From that point it's been pretty much using the Tablo exclusively. I have not used the MediaSonic TV tuner for an extended period of time.

That said, I'll do some experimentation and some longer viewing with it on the channels I've had issues with to see if there's anything unique with that (drop-outs or what-have-you.) Thankfully the Tablo has been recording what station, day, and times the problems are occurring. I'm starting to record that info in a spreadsheet to see if I can see a pattern or anything emerge.

It's not much, but one experiment I performed has been to find the pilot frequency for each channel using my Airspy R2 + SDR#. The Airspy has a wide enough bandwidth so I can see the "whole" signal at once. I used this to see what gain setpoints I needed to place that pilot frequency peak at -40dB to -45dB. The Airspy gain setpoints ranged from 3 to 13:

KFME: 6
KVRR: 7
WDAY: 3
KRDK: 8
K28MA: 13
KXJB: 8
KVLY: 10

I realize this doesn't show any sort of bit error info or whether I've got multipath issues going on, but I'm at least able to "see" things.

Thanks for help so far and relaying my posts to the thread!!!
Yes, you can see the whole channel with the Airspy R2 and SDR#.



For signal quality, SNR and errors, I use my SONY TV and a SiliconDust HDHR.

Bad signal



Good signal





Signal Quality is similar to SNR.

Symbol Quality is the inverse of uncorrected errors; it should be 100%.

Looking at the shape of a signal can help find the best location for the antenna.









The above three images were made with an SDRplay RSP1A and SDRuno software.
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Last edited by rabbit73; 1-Sep-2020 at 3:06 AM.
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