Microphone Removal And Replacement - Kirby Morgan KMB-18 A/B Operation And Maintenance Manual

KMB 18 & 28 MANUAL
Fig. 6.13 Inspect the mylar cones.
6.4.3 Microphone (12) Removal and Replace-
ment
Tools Required:
1/8 inch Flat Blade Screwdriver
The entire microphone (12) is replaced the same
as the earphones by removing the wire lugs from
the communications posts (73) or terminal block
(82) and replacing the entire unit.
1) Remove the nuts (71) and washers (72) from
the communications posts (73). If you are using
the optional terminal block (82) this may be
where the wires from the earphone and micro-
phone are connected.
Fig. 6.14 Remove the nut from the communications posts.
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© Copyright 1970-2003 Kirby Morgan Dive Systems, Inc. All rights reserved. Document # 010518001
2) Lift the terminal lugs off 0of the communica-
tions posts (73). Note the position of the terminal
wires.
3) Slowly pull the microphone (12) out of the oral
nasal mask (9). The wires that connect it to the
communications posts (73) will follow.
Fig. 6.15 Remove the microphone from the oral nasal mask.
4) The microphone (12) is of a special design for
underwater use. It has a felt backing that will
absorb salt water to help protect the microphone.
The microphone should be removed for periodic
cleaning. If salt has accumulated on the felt, it
(just the felt) should be dipped in warm fresh
water to remove the salt.
5) If you are installing a new microphone (12) or
reusing the old one it must be seated in the oral
nasal mask (9). Install the terminal lugs for the
new microphone (12). Note that the wires must
go on separate terminals as before.
6) Tighten the nuts (71) carefully, without turning
the communications posts (73). If the posts turn,
it means that the seal made by the silicone sealant
(RTV) on the mask frame has been broken. If this
happens the posts (73) will allow water to leak
into the mask. (See Section 6.4.6.2 for repair)