I know that this is a rather old thread that I have just come across when
cleaning
up my mail whilst waiting to fly through an ice storm to Boston.
Why do the manufacturers still bother with S units. Why don't receivers
just
measure dBuV or dBm at the antenna?
73
Strewart
Dick Rollema wrote:
To
All from PA0SE Walter, DJ2LF, wrote: But
nevertheless - what about S9 on LF is 500uV? I would prefer
to stick to S9 is 50µV over 50 ohms (or better S9 means -73dBm, to
make it independent of receiver input impedance) and one S-point
is 6dB. These are values recommended by IARU and therefore
can be considered as a "standard" that has been accepted internationally
(except by the receiver manufacturers). I don't think IARU has stated
a lower frequency limit, only that it should be used below 30MHz. Using
a new "standard" for LF would add to the confusion which is already big
enough. If it is nevertheless felt that S9 is 500µV would be better
for LF then this should be made a proposal to be presented at the next
IARU conferences in the three regions. 73, Dick, PA0SE
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