ZETRON 37-MAX, Installation Manual

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3-1
3. OPERATION
OVERVIEW
This section explains the general operation of the Repeater Pal on a top level, “big picture”
basis. The information presented here should be useful for evaluating a potential system
installation, as primer before jumping into the Programming section for the first time, and for
explaining system functions to users on the system.
This section starts out by explaining the relationship between the very often used term "user
number" and the decoding of a particular CTCSS tone or DCS code. After discussing some
additional user issues related to setting up a valid tone or code, the normal actions of the
panel while in normal operation are covered. The last portion of this section covers the
operation of system-wide timers and settings.
USERS VERSUS CTCSS/DCS DECODE
Since the Model 37-MAX is a multi-user repeater tone panel, it behaves as though it had a
separate decode/encode module for each user group it supports. In reality, this is achieved
using a single microprocessor controller and some very smart software to run it. The
advantages of this software approach are:
•
higher capacity than if we had built the panel using hardware modules. The Model 37-
MAX can decode and encode all 50 CTCSS tones and 104 of the DCS codes.
•
flexibility of configuration at a level that would be difficult to provide for even half as
many users if physical switches or jumpers were required to configure user or system
attributes
•
remote programming is as easy as (in fact, works the same as) local programming, which
means no more costly trips to the site just to alter a single user or system parameter
In order to reduce the number of commands used in programming and to bring some order to
the process of setting up user groups, the Model 37-MAX uses the concept of a "user
number" to program features related to a specific CTCSS tone or DCS code. There is a fixed
relationship between a user number and the tone or code to be decoded. The user numbers 1
through 50 are used for CTCSS tones (see Table 3. OPERATION -1) and the users numbers
51 through 154 are used for DCS codes (see Table 3. OPERATION -2). The user number "0"
is reserved for use with carrier squelch operations. For example, in Table 3. OPERATION -
1, the user number 36 corresponds to the CTCSS tone frequency of 186.2 Hz. In Table 3.
OPERATION -2, the user number 55 corresponds to the DCS code "032". These represent
the tone and code that would be decoded if these two user numbers were enabled. Table 3.
OPERATION -2 also shows an inverted code next to each of the primary DCS codes.
Inverted codes are described in “DCS Polarity” later in this section.