Figure 1-28.—Alarm switchboard visual displays and audible alarms.
coolant has entered the waveguide, it can flow
through the various sections of the waveguide
system. It can cross over to other waveguide systems
through the common dry air lines that are connected
to the waveguide. As you can see from the above
description, if the coolant leak is severe or remains
undetected for a long period of time, a leaking water
load can completely fill the waveguide system with
coolant.
You have to follow a logical troubleshooting
procedure. If the problem is a common one in a
specific combat system equipment, there will
probably be a technical bulletin issued that describes
how to isolate the flood damage. The following is a
condensed procedure for waveguide flooding.
ISOLATE EXTENT OF FLOODING
It is imperative that the amount of waveguide
contamination be determined before the microwave
system is drained of water. If the exact level of
contamination is not determined, many microwave
components may needlessly be removed and many
manhours expended unnecessarily. You will have to
secure the cooling system and close all valves to the
affected areas of the radar. If the cooling system uses
a pressurized expansion tank, you will have to bleed
off the air pressure. If you can still see the coolant in
the sight glass of the expansion tank, you can
estimate the amount of coolant missing since the
system was last filled. Use the estimated loss to
determine the amount of contamination that may
have occurred. The dry-air
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