Instruction manual

ACU-1000 Operations Manual
Interoperability Now 2-21
2.10.2.3 RADIO MODIFICATIONS:
Sometimes it’s necessary to make a physical modification to the radio. Usually this is required
because needed signals (such as a PTT input or a TX Audio input (MIC Audio) are not
available without the change. Sometimes these signals can be made accessible through radio
programming changes rather than hardware modifications. The Application Notes always
endeavor to provide the easiest possible interface method.
2.10.2.4 RADIO PROGRAMMING:
Al necessary or recommended changes to the radio programming are listed.
Raytheon JPS recommends that radios interfaced to the ACU-1000 rear panel be set for low
transmit power. The reason is that many Local Interoperability Systems have a number of
radios operating in close proximity, this increases the chance of radio front-end desensitization
and other problems likely a complex RF environment. Higher power exacerbates these
problems. This is particularly true of Tactical, Transportable, and Mobile Applications where
quick set up or a quickly changing RF environment is likely. If careful attention is paid to
antenna placement, the TX and RX frequencies used, as well as proper grounding and shielding
practices, it’s certainly possible to operate radios at a higher power setting, but stay aware of
the potential for problems.
Radio Programming functions that may be required are:
• Make signals accessible at the radio I/O (PTT, Mic In, COR, etc.)
• Set Channel Frequency
• Set power output for lowest reliable level
• Set CTCSS or DCS
• Squelch/COR pinout
• COR output: Active Hi or Active Low
• Program Squelch/COR output for carrier plus tone
• Set Minimum audio level
• Disable any off-hook setting
• Enable cable ignition sense
2.10.2.5 RADIO CONTROLS:
Any necessary or recommended radio control adjustments are provided. Many radios do not
have a constant volume Line Out, and the RX audio provided to the ACU-1000 varies with the
volume setting. If so, the proper setting is listed.