--- In ultralightdx@..., "Stephen" <pianoplayer88key@...>
wrote:

Also, speaking of the two 1580s... I don't have a recording of it now,

but I often hear rapid volume changing (several times per second) or
something when I hear both stations at the same time. Is that likely to
be the two station's carriers not quite perfectly on frequency, or is it
possibly soft mute?

They may be slightly offset in frequency, or it may be the phase
difference between the two carriers, which will vary due to ionospheric
conditions. Soft mute definitely exacerbates the flutter if the minimum
signal level drops below its threshold. Believe me, it's much worse on
the G8!

Regarding winding an air loop around the radio: It would take quite a
few turns to get enough inductance, and the circuit board etc inside the
coil would degrade the Q. A similarly sized loop a couple of feet away
from the radio would work far better.

73,

Jim, KR1S
http://qrp.kearman.com/