Park Air Systems T6TR, Пользовательская документация

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T6TR VHF 50 W Transceiver Page 2 Installation
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Warnings and Cautions
The instructions given in this topic involve connecting dangerous voltages to the transceiver
and should be carried out only by suitably qualified personnel.
The equipment is permanently connected to the mains supply when the mains connector is
attached. Switching the rear panel Power switch to off does not isolate all internal circuits
from the mains supply. For this reason, a mains isolating switch should be fitted close to,
and easily accessible from, the transceiver's position. The isolation switch should isolate
both live and neutral supplies, be clearly labelled, and adequately rated to protect the
equipment.
The antenna used with the transceiver must be installed such that the resultant radiated field
strength is below 10 W/m² in areas normally accessible to personnel.
The RF field strength from the antenna can be predicted from the equation S=1.4PG/4
π
R
2
[Where S = power density; P = power input to antenna; G = antenna gain; R = distance
to centre of radiation and 1.4 = multiplication factor for average power based on a
modulation index of 90%.]
Based on this formula for a 50 watt transmitter and using a 0 dBi antenna, the predicted safe
distance from the centre of radiation would be approximately 0.75 m for a field strength of 10 W/m
2
(1 mW/cm
2
).
This meets the requirements of Health Canada Safety Code 6 for RF and microwave exposed
workers. For persons not classed as RF and microwave workers and including the general public
the limit is 2 W/m
2
(0.2 mW/cm
2
) which increases the minimum safe distance to 1.7 m.
Further information on calculating the field strengths and power levels can be found in Health
Canada Safety Code 6 'Limits of Human Exposure to Radiofrequency Electromagnetic Fields in the
Frequency Range 3 kHz to 300 GHz', and also in FCC document OET Bulletin 65.
The T6TR transceiver's circuitry contains Electrostatic Sensitive Devices (ESSDs).
Personnel must be aware of the precautions necessary to prevent damage to such devices.
During installation all precautions necessary to prevent ESSD damage must be taken.
Changes or modifications made to this equipment that are not expressly approved by
Park Air, or parties authorized by Park Air, could void the user’s authority to operate the
equipment.
WARNING Dangerous Voltages
WARNING Dangerous Voltages
WARNING
Antenna Radiation
WARNING
ESSDs
Caution Unauthorized Modifications