the signal data converter, where it is converted to audio
tones and then transmitted out over the selected radio.
When the message is complete, REC (receive) is
selected on the keyboard. This selection allows the
system to receive phase tones and incoming messages
from other stations on the frequency.
The on-line mode is designed to simplify the work
of the operator. Actual system operation is covered in
various software publications. In general, the operator
types an outgoing message in the central computer. The
operator performs all the operations described above,
except XMIT is selected on the TTY keyboard.
Depression of the XMIT switch on the keyboard directs
the central computer to send the stored message through
Communications Interface No. 1 into the TTY system.
In the same manner, when REC is selected on the
keyboard and CMPTR selected on the HSP, any
incoming messages are sent to the central computer.
Currently, the computer has the ability to store one
message of approximately 800 characters for review by
the operator.
In addition to teletype data, the TTY system can
send and receive data to and from the central computer.
In input data, the operator simply selects CONST &
EDIT on the keyboard. Any keyboard depressions are
then sent to the central computer via the
communications interface.
To produce hardcopy of computer data, CMPTR is
selected on the HSP. Software functions then allow the
central computer to print data on the HSP via
Communications Interface No. 1. This data is sent at
3,000 words per minute regardless of the WPM SPEED
switch on the HSP.
Q1.
Q2.
Q3.
Q4.
Q5.
Q6.
Q7.
Q8.
Q9.
Q10.
Q11.
Q12.
Q13.
REVIEW QUESTIONS
What is the most important means of communi-
cating in the Navy today?
What frequencies are included in the super
high-frequency band?
How many LS-602/AI panels are there in a
typical aircraft?
What type of encoding/decoding is used in the
ICCG system?
What is the actual frequency range of the
AN/ARC-197 radio set?
How many preset channels are available with the
AN/ARC-187 radio set?
What fault is indicated when the fault indicator
on the C-11950/ARC-187 control box flashes at
a slow rate?
The HF-2 long-wire antenna has degraded
operation at which frequencies?
What is the purpose of the lightning arrester used
in the HF system?
What radio sets can be used with the data link
system?
Who has primary responsibility for the hardware
setup of the data link system?
Which unit in the TTY system provides the
interface with the radios?
Which unit connects the TTY system with the
central computer?
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