Lesson 2/Learning Event 6
b. Characteristics. This test set is entirely solid state, and is so
constructed that a wired circuit board is inserted to obtain the code
characteristics desired; that is, one board is used for the Baudot code
and a separate board is used for the ASCII code.
The codes are not
selectable merely by front panel switches. The circuit boards are easily
replaced.
(1) Signal types. Pulses may be transmitted either neutral or polar by
changing the strapping on the rear of the unit. Dry contact keying only
is provided; all loop battery must be supplied externally.
(2) Push buttons. Push buttons select the code character combination.
Only the first five are used for Baudot code, while all eight are used for
the ASCII data code.
Control
Indicator
Function
RELEASE INFO
Establishes the mode of operation.
SW Pos
Action
BIT SYNC
The data transmitter generates one bit
each time a trigger pulse is received
from the clock in the data analyzer.
FREE RUN
The
data
transmitter
continuously
generates the selected format at the
selected modulation rate.
Triggering
is not used.
STEPPED
The data transmitter generates one
character of the selected format, at
the selected modulation rate, each time
a trigger pulse is received from the
clock.
STEADY
The transmitter generates a continuous
MARK
mark signal.
There is no provision in
this test set to transmit a steady
space.
In a neutral circuit, it is
only necessary to open the loop for
space.
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