A typical marine radar on long range puts out a pulse of about 8/10,000 of a
second every 2/1,000ths of a second. It listens for the return from each
signal for about 3/10,000ths of a second which is enough time to get a
reflection from about 30 miles away. If a return is not within that time it
is discarded so two radars would have to be very closely in sync to
interfere with each other very much.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
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"Roger Long" wrote in message
...
Just one of those questions that you suddenly wonder why you never
wondered about befo

How do all those radar's out there avoid interfering with each other? Are
they all on slightly different frequencies (that seems like a lot of
frequencies) or do they just know that pulses that come back within a
narrow time window are the ones they sent out?

Larry?

--

Roger Long