
Document 8K088X04 R5.01
Portable Digital Repeater Programming Guide
Page 56 of 86
A
NALOG
C
ODE
T
ABLE
Multi-Coded Squelch (PL/DPL)
Multi-Coded Squelch is a feature commonly used in analog radio operation. Operation is driven
by the addition of a sub-audible tone on the RF carrier in addition to the voice payload. When
an RF signal is received, the receiver checks for presence of PL/DPL, and modifies its behavior
based upon detection of the decoded PL/DPL tones. In most cases, the receiving radio will
choose to either unsquelch, or mute the incoming signal based on the presence of the detected
PL/DPL.
PDR8000 allows each of its analog-enabled channels to be configured with a desired behavior
for utilizing PLs/DPLs. These behaviors are captured in Analog Code Tables. Each configured
channel in the PDR8000 can point to one of the configured Analog Code tables. Each table can
be used to define PL/DPL operation for a specific channel or may capture behavior shared by
multiple channels.
Within each Analog Code Table, exists a Multi-PL/DPL table defining the particular PL/DPL
values used to govern squelch code on the configured channel. The table consists of 14 rows,
having an Rx Squelch Code, a corresponding Tx Squelch Code, as well as parameters to
control Squelch Tail Elimination. In most cases, the table is configured for
Normal
operation,
allowing only the first row of the table to be used (see Table 1). If, however, the table is
configured for
Multi-PL/DPL
operation (see 0) then all 14 rows are available for use (each row
can then be individually enabled/disabled as desired.)
Rx PL Operation
Normal / Multi-PL/DPL
Row
Enabled
Rx Squelch Tail
Elimination (STE)
Rx Squelch
Code
Tx Squelch
Code
Tx Squelch Tail
Elimination (STE)
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 1
Tx Code 1
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 2
Tx Code 2
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 3
Tx Code 3
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 4
Tx Code 4
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 5
Tx Code 5
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 6
Tx Code 6
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 7
Tx Code 7
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 8
Tx Code 8
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 9
Tx Code 9
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 10
Tx Code 10
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 11
Tx Code 11
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 12
Tx Code 12
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 13
Tx Code 13
Off / DPL / -135 / +135 / 180
Y/N
Off / DPL / -135 / +135 / 180
Rx Code 14
Tx Code 14
Off / DPL / -135 / +135 / 180
Table 1: Analog Code Table
PL and DPL codes are predefined in a common way, to allow use across radios manufactured
by multiple vendors. The Rx and Tx squelch code entries in the table can be set to a defined PL
Code, a defined DPL Code, or set to OFF (Carrier Squelch operation).
Squelch Tail Elimination is a method used to prevent the receiving radio from hearing a brief
noise (squelch tail) at the end of each transmission. By having the transmitter provide a phase-