programming feature that can store up to 100
preprogrammed frequencies. A keypad is used to key in
frequencies either for use or program storage. The
receiver may scan any or all of the preprogrammed
frequencies to check for traffic on the frequency.
Operator maintenance is limited to scheduled
cleaning, visual inspection, and initiating a periodic
self-test routine. No special training or equipment is
required. The front panel should be checked once a day
for display of a fault condition to ensure that there is no
internal circuitry failure.
Details of these operator
maintenance procedures, as well as easy to follow
operator instructions, are contained in Technical
Manual Operation and Maintenance Instructions with
Parts List, Receiver R-2368/URR, EE125-FC-OMI-
010/R-2368/URR.
RECEIVER SWITCHBOARD
The receiver transfer switchboard allows you to
transfer the audio output from the receivers to remote
control station audio circuits. Figure 1-24 shows two
representative SB-973/SRT receiver transfer
switchboards. These switchboards contain ten 7-posi-
tion switches. Each switch is connected to a remote
station, such as a facsimile recorder, the TESS input
jack, or an audio speaker. Each of switch positions 1
through 5 relates to a receiver, which is usually
specified on an engraved plate along the top of the
switch case. In figure 1-24, only the first four switches
of each switchboard have been used, as seen by the
engraved equipment identification adjacent to each
switch. The position "x" on each switch allows you to
transfer the circuits to additional switchboards.
AN/URA-17 COMPARATOR-CONVERTER
A comparator-converter device is used to convert a
radio receiver’s frequency shift keying audio output
carrying radioteletype information into direct current
(dc) pulses compatible with a teleprinter.
The
comparator-converters currently used aboard Navy
ships are the AN/URA-17(B) or (C) versions (fig.
1-25). A group consists of two CV-483/URA-17
frequency shift converters cross connected with a
wiring harness. The output of each CV-483 is hardwired
into receiver transfer switchboards, and usually
identified as URA-17 "A" for the top converter, and as
AN/URA-17 "B" for the bottom unit.
Two converters are supplied so that the user may
tune in the same radioteletype broadcast on two
separate frequencies with two radio receivers, and feed
the output from both converters into the same printer.
This method of copying a radioteletype broadcast is
Figure 1-24.—SB-973/SRT receiver transfer switchboards.
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