SLOW
45.5 BAUD
60 WPM
55 BAUD
75 WPM
FAST
75 BAUD
100 WPM
Figure 1-27.—CV-483 CRT signal patterns. View (A) shows a
properly tuned signal, view (B) frequency is too high, view
(C) frequency is too low, view (D) the CV-483 level is too
low, and view (E) the CV-483 level is too high.
Table 1-6.—CV-483 Speed Setting Compared to RATT Baud
Rate and Printer Word-Per-Minute Settings
4. Using the transfer switchboard, you may now
connect the CV-483(s) to a teleprinter or TESS HF
RATT input and switch the CV-483 function switch to
the "single" setting. If the printer appears to be printing
garbled letters and numbers, switch the "polarity"
switch to the "reverse" position. If still printing garble,
adjust the "speed" switch to "slow" and adjust the
printer Words Per Minute (WPM) or Baud rate setting.
Baud is the rate of modulation of a transmitted signal.
The words-per-minute figure is an approximation based
on the relationship that one word is six-unit characters
of information. Baud rate times 1.35 is the approximate
WPM rate. The CV-483 speed is related to transmission
baud rates and WPM rates, as shown in table 1-6.
SHIPBOARD TELEPRINTERS
Observers in shipboard meteorological offices
equipped with the TESS (3) or later versions of TESS
may direct HP RATT signals into the TESS system for
automatic sorting, storage, selected recall and display,
or printing of alphanumeric information. IMOSS can
also be used to copy RATT data. On ships not equipped
with TESS or IMOSS, the incoming information must
be directed to a printer. Currently, there are two basic
types of shipboard teleprinters in use: the Teletype
Corporation Model 28 (several different versions) and
the Navy Standard Teleprinter (NST), the AN/UGC-
143A(V).
Model 28 Teleprinter
The Teletype Corporation Model 28 teleprinter is a
family of reliable low-speed teleprinters. Some
versions are not equipped with a keyboard, and are
known as receive-only (RO) teleprinters. Other
versions have a keyboard and are known as Keyboard
Send-Receive (KSR) teleprinters. In one version or
another, Model 28 printers may still be found in
shipboard meteorological offices. Some of the basic
versions of the Model 28 are the TT-48/UG floor-
mounted KSR teleprinter (fig. l-28), the TT-69/UG
tabletop KSR teleprinter (fig. l-29), the AN/UGC-20
compact KSR teleprinter (fig. l-30), and the AN/UGC-
25 compact RO teleprinter (fig. 1-31).
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