Quote:
Originally Posted by richardrosa
This is one of the many things that drives me CRAZY about digital. Back in analogue days, intermod/crossmod was always observable, and you knew what was going on. Now all you get is "No Signal" (which is a LIE). Without a good spectrum analyser you cannot tell what is happening.
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Yes, the sudden loss of the digital signal at the Digital Cliff makes it difficult to solve reception problems. With analog, we had a rough idea of the strength of the signal by how snowy it was. With digital, we don't know if it is even there, much less how strong it is, when the tuner can't pick it up during a scan.
The sudden drop off at the digital cliff is caused by the FEC, Forward Error Correction. The tuner is able to correct digital errors up to a certain point. When that limit is exceeded, the remaining errors are uncorrected and we reach the digital cliff with pixelation, picture freeze, and finally dropout.
Many people asked me how can we tell if a signal is there when the tuner doesn't pick it up? As you said, a spectrum analyzer is the ideal tool, but they are expensive. I found that even an old analog meter will do the job. I can turn on the audio and listen for the digital signal as I watch the needle on the panel meter. The digital signal is actually an analog AM signal that carries the digital information. It sounds like white noise, and I listen for an increase in noise above the noise floor.
I don't have any experience with the Solid Signal meter, and I am not certain that it will help you any more than your present meter, but it is able to measure signal quality in addition to signal strength. In the UK a CAI (Certified Aerial Installer) is required to measure signal strength AND signal quality.
The customer reviews on Amazon look OK and this review was done for SS:
http://forums.solidsignal.com/conten...ctrum-Analyzer
this is the manual from the manufacturer's site <www.emitor.se>
http://www.emitor.se/index_htm_files...2013_2_ENG.pdf