Sailaway wrote in news:FX_Rg.4099$KF6.3557
@newsfe09.lga:

Just curious... Don't the marine radars have blanking, an adjustable
point where the radar emits no signal - so a mast wont reflect directly
back into the mast-mounted antenna? Or have masking, where the receiver
ignores returns that are too close - like from the mast or rigging?


otnmbrd wrote back:
no...... in fact, not too many shorebased sets do either although some
will have a setup where the actual picture is blanked out.

Interesting. I brought it up because way back when I was in the Navy *A
school* for avionics I remember learning about those things. Never
worked on radar though, except the ancient ones in the school.

On Mon, 25 Sep 2006 22:23:01 -0400, Sailaway
wrote:

Sailaway wrote in news:FX_Rg.4099$KF6.3557
:

Just curious... Don't the marine radars have blanking, an adjustable
point where the radar emits no signal - so a mast wont reflect directly
back into the mast-mounted antenna? Or have masking, where the receiver
ignores returns that are too close - like from the mast or rigging?


otnmbrd wrote back:
no...... in fact, not too many shorebased sets do either although some
will have a setup where the actual picture is blanked out.

Interesting. I brought it up because way back when I was in the Navy *A
school* for avionics I remember learning about those things. Never
worked on radar though, except the ancient ones in the school.

You may be thinking of the T/R cell which shorts the receiver out
during transmitter pulse time.
Then a swept gain control shapes the receiver gain with distance -
low for near targets, high for distant ones

Brian Whatcott Altus OK