I’m experiencing constant pixelization and weak signal pop-ups with the 2-tuner Fire TV Recast on WFYI channel 20–1 (physical CH 21) in Indianapolis. Watching the input signal on a spectrum analyzer simultaneously with the screen finds no obvious interferer and only small variations in signals (due to winds and foliage?). The signal shouldn’t be considered weak, however. In the attached spectrum scan at 512 MHz center, 2 MHz/div, 10 dB/div, video filtered, the top graticule line is -27 dBm, so the “carrier” peak on CH21 is at -45 dBm and probably fractionally higher because the attic antenna/preamp/feedline/splitter are 75 ohm but the analyzer is 50 ohm. The lower adjacent CH 20 (below the center frequency) is at nearly the same bearing, higher power, higher elevation but its signal is always well within 10dB of the desired CH 21 and the Recast should be able to reject it. The CE at WFYI has received no other trouble reports with Recast and told me there is nothing exotic about WFYI’s multiplex. The other locals we care about are -55 dBm or higher and all are solidly received, as is the second adjacent CH 19 which appears in the spectra at -63 dBm.
The left-rewind menu I found as a suggestion on this forum worked two or three times for a few seconds but not long enough to scroll or read any data and now it no longer works at all. Is there any other way to diagnose the signal characteristics or what error(s) the receiver or demodulator are throwing?