2
947923
Specifications
The timing and frequency specifications of the
Valcom V-9923B code call unit are shown in Table
2. Figure 1 is a timing chart showing the nominal
timing of a code call.
Table 2
Dial Tone Frequency
180 Hz
Coded Tone Frequency
550 Hz
Time Tones Broadcast
370 ms
Time between tones in a sequence
500 ms
Time between digits in a sequence
1.5 sec
Time between series of digits
8 sec
The Valcom V-9923B will detect 20-30 Hz ringing
on the answer port. The applied ringing voltage
should be 75 to 125 Vac.
DESIGN
The V-9923B provides two or three digit code call
paging via a loop start trunk port on a PABX or by
the use of a spare line button on a key system. Figure
2 is a simplified block diagram showing the code call
unit and its connections.
NOTE: The code call unit is designed so that it will
complete a code call sequence before resetting and
returning dial tone, even if all parties hang up.
Application
Key systems and PABX's used in:
•
Department stores/shopping centers
•
Hospitals, nursing homes
•
Noisy locations, manufacturing plants
•
Schools, universities
Additional Materials Required
Additional equipment is required to complete a
system when using the V-9923B. These items are:
•
-24 Vdc power supply (if existing supply
inadequate or non-existent)
•
66 type connecting block
•
25 pair cable with a female amphenol connector
on one end
•
twisted pair crossconnect wire
TONE ON
TONE OFF
.37 sec.
.50 sec.
1.5 sec.
1.5 sec.
8 sec.
"3"
"1"
"2"
"3"
"1"
SEQUENCE
BEGINS
SEQUENCE
BEGINS
AGAIN
CONTINUES UNTIL
ANSWERED OR
CALLING PARTY
GOES ON HOOK
FIGURE 1
