Connect Systems Inc. - Model 9800 Page 4
INSTALLATION AND ADJUSTMENTS
The 9800 contains both a noise squelch and COS circuits with COS
input. This gives the 9800 a great deal of interface flexibility. The
audio takeoff point can be anywhere from the FM detector (pre-
emphasized audio) to the volume control (de-emphasized or flat audio).
If connection is made to the FM detector, only three connections are
required to most radios. When connecting past the FM detector, a
fourth COS connection must be made. Use shielded wires with the
shields at both ends connected to chassis ground. (The rear panel
barrier strip terminals labeled "GND" are chassis ground). We
recommend using spade type crimp-on connectors for ease and
reliability. Connect the center wires as follows:
AUDIO IN: The audio input terminal may be connected directly to the
FM detector output, or to the high end of the volume
control.
If connecting to the FM detector...
1. A COS connection to the receiver is not required.
2. The de-emphasis strap JP-5 must not be cut.
3. The COS polarity strap JP-6 must not be strapped.
4. The noise control P2 must be adjusted to illuminate
the front panel noise LED. See "P2 NOISE" page 7
for further explanation.
If connecting to the volume control high side...
1. A COS connection must be made.
2. Cut JP-5 to eliminate built-in de-emphasis.
3. JP-6 must be strapped for the appropriate COS
polarity.
4. The noise control P2 must be set at minimum. (fully
CCW).
5. The COS threshold control P11 must be set to match
the level of the COS takeoff point.
See the appropriate sections below for detailed
directions.
Note: Connection must be made to the FM detector if you
wish to use the Sampling Simplex mode. A COS interface is
not quick enough.
COS: Note: The COS input is normally not connected if the
AUDIO IN is connected directly to the FM detector.
The COS input can be connected to the noise squelch for
carrier operation, or to the DPL/CTCSS squelch if you
want the radios' built-in decoder to provide private
operation.
