Julian transmitted with a power of 1 mW and 20 mW.
The table shows, that the spots that were made with 1 mW,
were about 10 dB weaker than the spots made with 20 mW
The table shows a selection stations that received spots made with both 20 mW and 1 mW
To compare spots over different distances, I use the
Calculated electrical field strength, E, in microVolt per meter.
For details see the WSPR Propagation Analysis page of this Blog.
The lower the electrical field strength the better the propagation.
A power ratio of 10 means 10 dB.
Please notice the the value for E is given in Volt/m, so a Voltage ratio of 10 means 20 dB.
Which is indicated at the top of the table.
A Voltage ratio of 10 is a ratio of 100 in power.
The table shows stations that received the signals, that were transmitted with 1 mW and 20 mW.
Notice the difference in field strength in spots made with 1 mW or 20 mW.
The difference in field strength between the spots of 1 mW and 20 mW is about two steps in this table.
This is about 10 dB.
This is about 10 dB.
This is no surprise because, the difference in power between 1 mW and 20 mW
is 10 log (20 / 1) = 13 dB.
The differences in propagation are huge.
The field strength of the spots made with 20 mW, received by ON7KO over 600 km,
show a value of 0,3 microV/m to 0,03 microVolt/m.
The ratio in voltage is 10 and the ratio in power is 100, which is 20 dB. Wow.
Always enjoy reading your digital blog...even though I am still all cw.
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