Lesson 3/Learning Event 4
b. Circuit Patch Bays. Circuit patch bays 4 and 5 provide an equal-
level patching point for all circuits routed through the van. The circuit
jackfield, VF amplifiers, loop to E&M converters, a 20-Hz ringing supply,
line test equipment, tone generator, and a writing shelf.
c. VF Test Bay. Bay 6 contains the test equipment to perform routine
checks and evaluation of VF lines. It provides the means for connecting
the test equipment to operating channels by means of miscellaneous
jackfields. The test bay has a loudspeaker and amplifier assembly, signal
and line test equipment, an operator's telephone, and a miscellaneous
d. Signaling Bays. Bays 14, 15, and 16, shown in figure 3-6, contain
Learning Event 4: PLAY LAYOUT, LEFT SIDE, AN/MSQ-73
The plan layout of the left side includes the combined distributing
frame, the DC patch bays, a teletypewriter deductibles bay, and a
a. DC Patch Bay. Bay 7 and 8, shown in figure 3-7, provide patching
for teletypewriter traffic send and receive circuits. This DC patch bays
contain send and receive jackfields, line isolation relays, and a 6-volt
b. DC Test Bay. Bay 9 is a DC test bay. It contains a miscellaneous
jackfield, two DC meters on a panel, a distortion (digital) analyzer, an
operator's telephone, and a 130-volt DC supply for telegraph loop current.
c. Teletypewriter Monitor Bay.
Bay 10, shown in figure 3-7, is the
teletypewriter monitor bay. It houses a keyboard and three page printers
One page printer, together
with the keyboard, makes up the telegraph order wire.
The second page
printer is used for monitoring 60-wpm circuits, while the third is used
for monitoring 100-wpm circuits.
d. Selectable Channel Monitoring Bay.
Bay 11 (figure 3-7) contains
the major parts of Telegraph Terminal AN/FCC-l9, Demodulator AM-1220/FG,
and a station alarm system.