I have followed this discussion with interest. I used a time sync =
program before I got into seismology -- almost ten years ago. Syncing a =
local network is a lot easier than time syncing WinSDR. One of the =
drawbacks of using Internet sources to set time is that the source is =
not available all the time. Maybe, your provider isn't doing maintenance =
or isn't slowed down by heavy demand like mine is at times or the =
provider may even be shut down by viruses or mechanical problems in the =
lines or center computer breakdown. Certainly access to a time source =
will NOT be as dependable as you think.

Chris has a point, too, about the computer we use with the detection =
equipment. I doubt many of you use the newest computer to run WinSDR -- =
it is overkill. But the older computers ARE slow to multitask and their =
clocks are not that stable. I don't see Larry's GPS board that big an =
expense for the accuracy it provides plus it is easy to install.

I might also add that variations in dependability in over-the-air =
reception should be expected as well; there is day-to-night, sun spot =
interference -- even the arrival of long path-short path signals at the =
same time and place can be a problem . There is also human created noise =
such as power generators that carpenters use to power tools at =
construction sites, even legal amateur radio broadcasting, broken =
insulators on nearby power poles and by all means drift in the receivers =
being used to capture time pulses over the air.

GPS is best for no other reason that it operates in frequencies above =
the normal interferences -- it comes from straight up there -- with no =
bending over the horizon







I have followed this discussion with =
interest. I=20
used a time sync program before I got into seismology -- almost ten =
years ago.=20
Syncing a local network is a lot easier than time syncing WinSDR. One of =
the=20
drawbacks of using Internet sources to set time is that the source is =
not=20
available all the time. Maybe, your provider isn't doing maintenance or =
isn't=20
slowed down by heavy demand like mine is at times or the =
provider may=20
even be shut down by viruses or mechanical problems in the lines or =
center=20
computer breakdown. Certainly access to a time source will NOT be as =
dependable=20
as you think.
 
Chris has a point, too, about the =
computer we use=20
with the detection equipment. I doubt many of you use the newest =
computer=20
to run WinSDR -- it is overkill. But the older computers ARE slow to =
multitask=20
and their clocks are not that stable. I don't see Larry's GPS board that =
big an=20
expense for the accuracy it provides plus it is easy to =
install.
 
I might also add that variations in =
dependability=20
in over-the-air reception should be expected as well; there is =
day-to-night, sun=20
spot interference -- even the arrival of long path-short path signals at =
the=20
same time and place can be a problem . There is also human =
created=20
noise such as power generators that carpenters use to power tools at=20
construction sites, even legal amateur radio broadcasting, broken =
insulators on=20
nearby power poles and by all means drift in the receivers being =
used to=20
capture time pulses over the air.
 
GPS is best for no other reason that it =
operates in=20
frequencies above the normal interferences -- it comes from straight up =
there --=20
with no bending over the horizon