------------ ORIGINAL MESSAGE ------------(may be snipped)
On Sun, 20 Dec 2015 11:19:58 -0800, W0YK wrote:
>My point is that 10 meters is open more often than we realize. It may not
>be apparent, though, until someone transmits.
REPLY:
So true!
There is another way of checking for an open band. I listen for the
backscatter echoes of my own signal. If you have a QSK amplifier, and
you are transmitting a carrier mode like RTTY, you should be able to
hear a "ping" echo of your own signal when you go from transmit back
to receive. A sharp, shot ping indicates an opening to a relatively
narrow area, whereas a broader, longer ping indicates multiple echoes
from a wider area. Rotating the beam will pinpoint the general
direction.
Listen closely because the ping is easy to miss if you're not paying
attention. An echo from 1500 miles away (roundtrip of 3000 miles)
takes only 16 milliseconds, so your QSK has to be faster than that.
Generally, the echo is weak, even with 1500 watts and a beam. With 100
watts and a dipole the band would have to be REALLY open to hear
yourself, but I suppose it is possible.
Been doing it for years, works great. But of c bourse, you still need
someone at the other end.
73, Bill W6WRT
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