The Pegasus Programmer's Reference Guide (PRG) says that the signal strength
query returns results that represent S-Units (and fractional S-Units). This
makes it pretty easy to display signals up to S-9, but what about signals
stronger than S-9? Most people expect a meter calibrated in db over S-9. I
designed my display assuming 6 db / S. Thus S10 would be 6db over S9, S11 12
db over S9. S13 18 db over S9, and so on. While I don't have radios setup
for side by side comparisons, it seemed that the strong signals on 75 were
reading higher with this display scheme than I saw on other radios.
Then today, I'm reading a 1296 MHz antenna review in the latest QST and the
author says the signals went from S3 to S8, an increase of 15 db. That's
only 3 db per SUnit.
So, just what is the relationship between db and SUnits?
Thanks and 73,
Mark
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