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Gentlemen,
sorry, but in my humble opinion a figure like
"miles per watt" just doesn't make any sense.
Fieldstrength goes with the square root of
power, but decays at least proportional to inverse distance.
Anyone could claim 1000 lightyears (1E16 km
!) per watt, simply by feeding -165 dBm into a pair of 144 MHz
dipoles spaced by 0.3 m and a QRSS3 receiver.
A more appropiate figure would be
km/sqrt(watt).
Best regards,
Markus (DF6NM)
----- Original Message -----
Sent: Friday, March 27, 2009 3:27
PM
Subject: Re: LF: Lazy Man's CW made it to
Venus and back
Dave,
If I got it right
their ran 5kW into a 20m dish at 2.4GHz.
The dish gain should be about
50dBd.
50dB = 100000 times power gain, thus ERP = +/- 500MW
The distance
to Venus (today) is 0.281 AU = 42 milion km = 26.1 milion miles
Total
distance is 82 milion km / 52.2 milion miles, what makes it +/- 0.1 miles
per Watt.
That value is not spectacular at all, but take into account that
Venus is a pretty bad reflector and the signal has to go twice trough
the atmoshpere and ionospere.
73, Rik ON7YD
Quoting
Dave Pick <[email protected]>:
>
How many miles per Watt is that?!!
>
> Dave
'YXM
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