SureCall GuardianA, User And Installation Manual

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Note: You may not need antennas on every floor of a multistory building, depending on factors such as building material, BDA
gain, etc.
3.4 Antenna Separation
Proper antenna separation prevents signal oscillation (feedback) that can interfere with the radio tower. Separation is
measured in a straight line from the exterior antenna to the closest interior antenna. The closest allowable distance depends
on a number of factors, such as BDA gain level, building material, etc. Recommended separation distances are:
Amplifier gain Min. separation (ad)
40 dB 5’-6’
45 dB 15’-20’
50 dB 50’
55 dB 60’
65 dB 75-80’
70 dB 100’
75 dB 100’-120’
80 dB 120’-180’
Vertical separation is more important than horizontal separation. If you are unable to obtain the required separation
horizontally, try raising the exterior antenna. You may also try reducing the BDA gain as described in Chapter 5 of this manual.
Antenna Safety Precautions:
You can mix and match dome and directional antennas as needed to obtain proper coverage throughout the building or
area where you need to boost the signal. If you use a Yagi exterior antenna, you should normally aim it away from all interior
antennas, regardless of separation, to prevent oscillation.
CAUTION: SIGNAL OSCILLATION CAN CAUSE RADIO
INTERFERENCE WITH RADIO TOWERS AND RESULT IN
CIVIL AND/OR CRIMINAL PENALTIES.
OK
Antenna Aiming
Planning the Installation