6K V1.02 03-16-91
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THEORY OF OPERATION
1.
INTRODUCTION
Great care was taken in the design of your controller to make it "installer-friendly." Audio and logical
interfaces were made as universal in nature as possible, so that a minimum of external hardware is
needed to complete the installation. Although the controller's "engine" is a powerful
microprocessor, the command language is designed to be easy-to-learn and flexible.
2.
PRE-PROGRAMMING (DEFAULTS)
The controller needs to know your repeater's call sign for its identifier; you must also tell it your
choice of courtesy message, timeout timer, and so on.
You can program the controller on your workbench with an external DTMF pad and other devices to
simulate the repeater. Or, you can install the controller in your repeater and program it through one
of the receivers, or the phone line.
To make the installation easier, the controller comes "pre-programmed" with certain
default
information stored in its non-volatile memory. When you have finished the installation, you may
overwrite this default information by entering DTMF commands. If it ever becomes necessary to
force the controller into its original default condition again, you can accomplish this by using the
initialize
pushbutton and a power-up sequence (the procedure is explained later). This procedure
causes the microprocessor to read default information from the EPROM and write it over the old
information stored in the non-volatile memory.
3.
POWER REQUIREMENTS
Your controller has only a modest power requirement, which can be supplied by the repeater's own
12 V power supply in most cases.
The controller's Main Board and Telephone Interface Module together require 12 V to 15 V DC at
less than 100 mA. (Do not exceed 15 V or damage may occur). The controller does not require
regulated power, since it contains internal voltage regulators to create the necessary 10 V audio
supply and the 5 V digital supply. A third supply of 4.5 V is created from the 10 V audio supply, and
is used as the audio section's bias voltage.
4.
REPEATER INTERFACING
Besides the power supply, the controller requires a minimum of four connections to the repeater.
They are: (1) Receiver COR; (2) Receiver Audio; (3) Transmitter PTT; and (4) Transmitter Audio.
You must eliminate any paths that might bypass the controller. In other words, there must not be
any connection from receiver audio to transmitter audio or from receiver COR to transmitter PTT
except through the controller. Otherwise, the controller will not be able to fully take charge of
repeater control functions.
If you require subaudible tone operation, you may connect a CTCSS decoder's output to the
controller. The controller will then allow you to switch the repeater from carrier operation to one of
