GAI-Tronics MRTI 2000 (No. PL1877A) Microprocessor Radio Telephone Interconnect Installation & Service Manual - Manual (Page 127)

PL1877A Microprocessor Radio Telephone Interconnect Features
121 12/10
Multi-Mode Selective Signaling
When the PL1877A is programmed for multi-mode selective signaling, the user enters only the required
user ID (from 00 to 99). The capcode is already preprogrammed as part of the user ID.
Overriding Certain Restrictions for Individual User IDs
Each user ID can be assigned certain properties that allow it to bypass specific restrictions on selective
signaling. For example, if group calling is disabled via parameters 1009, 1010, or 1011, you can
specifically allow it for an individual user ID. Refer to page 124, which describes the multi-mode paging
table.
Capcode Characteristics
DTMF
DTMF capcodes consist of 1 to 6 digits. For single-mode paging, the PL1877A can be programmed to
generate a 1-9 digit preamble (parameters 1131-1139) prior to the DTMF capcode. For multi-mode
paging, you can specify 1-15 DTMF digits for each user ID.
2-Tone
The 2-tone capcodes consist of 3 digits that specify 2 tones (the A tone and the B tone). The frequencies
for the A and B tones are determined from Tables 1 and 2 on pages 131 and 132 according to the
following procedure.
Suppose you wish to determine the frequencies for capcode 765 when the selected codeplan is R
(parameter 1129 = $16). Locate the chosen code plan in Table 1. From the same table, locate the most
significant digit (MSD) (7 in this example) of the 2-tone capcode. Next, determine the two-digit number
that appears at the intersection of the codeplan row and the MSD column (62 in this example). The first
digit of this number (6 in this example) corresponds to a number under “Chart A Group #” (Table 2) and
indicates which row of frequencies in Table 1 is used for the A tone. In this example, the A tone number
is 6, which corresponds to 1321.2 Hz. The second digit of the number from Table 1 (2 in this example)
also corresponds to a number under “Chart A Group #” and indicates which row of frequencies in Table
2 is used for the B tone. In this example, the B tone number is 5, which corresponds to 746.8Hz.
Plectron
Plectron capcodes consist of four digits that specify two tones (the A tone and the B tone). The
frequencies of the A and B tones are determined from Table 3 and Table 4 on pages 133 and 134
according to the following procedure:
Suppose you wish to determine the frequencies for the Plectron capcode 3456. The first two digits of the
capcode (3 and 4 in this example) are located on the Plectron Code Plan chart (Table 3). In the column
beneath this two-digit number, there are two P numbers (P5 and P6 in this example) that correspond to
tone groups in the Plectron Tone Group/Frequency Chart (Table 4).
Using the P number for the third digit of the capcode, determine the correct tone group from Table 4.
The frequency of the A tone (330.5 Hz) is found by locating the intersection of the tone group row with
the column headed by the third capcode digit (5 in this example). The frequency of the B tone (564.7 Hz
in this example) is found in the same manner by using the tone group for the fourth capcode digit as
listed in the Plectron Code Plan Chart (Table 3).
2805/1500Hz Paging
The 2805/1500 capcodes consist of 1 to 6 digits. For single-mode paging, the PL1877A can be
programmed to generate a 1–9 digit preamble (parameters 1147-1155/1156-1164) prior to the 2805/1500
capcode. For multi-mode paging, you can specify 1-15 2805/1500 digits for each user ID.