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SYSTEMFLOW AND TALON WIDEBAND SIGNAL RECORDERS
Recording solutions accelerate system development, performance and deployment
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USE CASE
Recording Radar Signals on Rotating Radar Dish
Engineers need to trouble shoot erratic behavior on a rotating radar dish antenna
mounted atop a truck. They suspect that one or more of the slip rings that carry power,
control signals and antenna signals through the rotating joint between the truck and
the antenna were defective.
To pin-point the problem they need to record both
transmit and receive signals on the antenna itself
before they went across the slip rings. They securely
mount a 2-channel Mercury Talon RTR Recorder on
the rotating antenna platform and power it with DC
power coming through the slip rings. They connect
one recorder channel to the IF output of the receiver
going to the slip rings and connect the other channel to
the IF transmit signal coming from the slip rings. They
start recording both channels with the GPS receiver
enabled to time stamp the recorded samples. They
start the antenna rotating at a known time, and increase
its rotation speed in steps at 30 second intervals.
After 20 minutes they stop the test and brought the
recorder back to the lab. When they play back the
two recordings, they found that the antenna signal
dropped out at the time stamp corresponding to the
14th, 15th and 16th rotating speed steps, but was OK
for all other speeds. The slip ring assembly was torn
down and the problem was traced to a visibly worn
antenna ring that became intermittent due to vibration
at those three speeds. Without the recording, they
could not have proved which ring was defective.
They were also able to add a metal support bar to
greatly reduce vibration at the troublesome rotating
speeds to reduce future wear of the new slip rings.
