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I recently bought a WINTV-D card installed it in a PC so that I could use its diagnostics program to evaluate antenna installations. In particular, I wanted to use its bit-error-rate counter. While I own a Blonder-Tongue BTSA-5 spectrum analyzer and a Drake TSM-1000, neither of these instruments allows me to assess the undesired component (multi-path) of the signals being evaluated.


Tonight, I powered it up for the first time and so far, I am disappointed with what I seem to have discovered. I used a VHF rabbit ear antenna on a 3 foot cord as my signal source. I am about ten miles from four DTV transmitters. I found the BER indicator to be virtually useless in peaking my antenna. Basically, once the signal improved to the point at which it produced a picture, the error rate became zero.


As I understand it, if I am receiving a slightly defective signal from which my tuner develops correctable errors, my board will still output a visually perfect picture. But, when peaking an antenna, I want more than that. I want to develop an antenna signal that causes the fewest correctable errors to begin with.


Is it possible that the errors-per-second number displayed by the WINTV-D board is the post-correction, uncorrected errors-per-second? If that is the case, then it won't be very useful to me.


Sencore has a model AT 1506 8VSB RF signal analyzer that displays parameters called "pre RS BER", "SER", and "post FEC". Unfortunately, it costs about $8,000, so I put together my portable WINTV-D signal monitoring assembly in hopes of it functioning as a suitable BER meter until someone incorporates that measurement feature in a less expensive meter. I have a hunch that the pre RS BER is what I should be trying to peak (meaning zero-out). Can any computer guys out there define those three terms for me, so that I can better decide if the Sencore meter will do something useful for me that the WINTV-D bit-error-rate meter does not?
 

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Sencore has a model AT 1506 8VSB RF signal analyzer that displays parameters called "pre RS BER", "SER", and "post FEC". Unfortunately, it costs about $8,000, so I put together my portable WINTV-D signal monitoring assembly in hopes of it functioning as a suitable BER meter until someone incorporates that measurement feature in a less expensive meter. I have a hunch that the pre RS BER is what I should be trying to peak (meaning zero-out). Can any computer guys out there define those three terms for me, so that I can better decide if the Sencore meter will do something useful for me that the WINTV-D bit-error-rate meter does not? [/b]

By guess or by golly:


pre RS BER = pre Reed-Solomon Bit Error Rate. This would be the raw error rate.


SER: Segment Error Rate.


post FEC: Post Forward Error Correction.


These seem like reasonable guesses. Further interpretations, corrections welcome.
 
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