User Manual

Table Of Contents
Notices Notices-iiPTX-PRO User and Technical Manual
WARNING - RF Power Hazard
High levels of RF power are present in the unit. Exposure to RF
or microwave power can cause burns and may be harmful to
health.
Remove power from the unit before disconnecting any RF cables
and before inspecting damaged cables and/or antennas.
Avoid standing in front of high gain antennas (such as a dish
antenna) and never look into the open end of a waveguide or
cable where RF power may be present.
RF Exposure - Safe Working Distances
MRC provides this warning for safety purposes with the intent to
inform the user of the potential hazard of RF exposure. The
following guidelines for safe operation were derived from OET
bulletin 65, August 1997, as recommended by the Federal
Communications Commission (FCC).
The PTX-PRO 13 GHz Transmitter is a mobile transmitter
system designed to provide services to broadcast ENG users
under CFR 74 subpart F and 74.601 TV pickup stations. This
unit, operated without an antenna, will not create RF energy
exceeding 1.0 mW/cm
2
, the FCC limit for exposure. Once
connected to an antenna, the potential for harmful exposure will
be greatly enhanced.
In this situation, a certain distance from the radiator is to be
maintained. Calculations need to be performed to understand
what that safe margin for exposure is. This is known as the
Maximum Permissible Exposure (MPE) limit.
Note
Hazardous RF radiation limits and recommended
distances may vary by country. Ensure that all
applicable state and federal regulations are
observed when using this transmitter.
Calculations provided are for common antennas often utilized in
the ENG environment. The following formula used is that
suggested by OET 65.
Calculating MPE
EIRP = P * (10 ^ (G / 10)) = (antilog of G/10) * P
P = RF power delivered to the antenna in mW
G = Power gain of the antenna in the direction of interest relative
to an isotropic radiator
R = distance to the center of radiation of the antenna in
centimeters
S = MPE in mW/cm² (milliwatts per square centimeters)
Conversions
dBi to numeric gain = Antilog (dBi/10)
Feet to centimeters = Feet * 30.48
Centimeters to Feet = cm * .0328
4 π = 12.57
User Input
RF power delivered to the antenna = Watts
Antenna gain (referenced to isotropic antenna) = dBi
Distance from the center of radiation = Feet
Calculation steps: