Broadcast Electronics Marti Electronics ME-40, Manual

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©2011 Broadcast Electronics
HIGH VOLTAGE –
Many power circuits operate at voltages high enough to kill through electrocution. Personnel should
always break the primary AC Power when accessing the inside of the transmitter.
RADIO FREQUENCY RADIATION -
Exposure of personnel to RF radiation should be minimized, personnel should not be permitted in the
vicinity of open energized RF generating circuits, or RF transmission systems (waveguides, cables,
connectors, etc.), or energized antennas. It is generally accepted that exposure to “high levels” of
radiation can result in severe bodily injury including blindness. Cardiac pacemakers may be affected.
The effect of prolonged exposure to “low level” RF radiation continues to be a subject of
investigation and controversy. It is generally agreed that prolonged exposure of personnel to RF
radiation should be limited to an absolute minimum. It is also generally agreed that exposure should
be reduced in working areas where personnel heat load is above normal. A 10 mW/cm
2 per one
tenth hour average level has been adopted by several U.S. Government agencies including the
Occupational Safety and Health Administration (OSHA) as the standard protection guide for
employee work environments. An even stricter standard is recommended by the American National
Standards Institute which recommends a 1.0 mW/cm
2 per one tenth hour average level exposure
between 30 Hz and 300 MHz as the standard employee protection guide (ANSI C95.1-1982).
RF energy must be contained properly by shielding and transmission lines. All input and output RF
connections, such as cables, flanges and gaskets must be RF leak proof. Never operate a power tube
without a properly matched RF energy absorbing load attached. Never look into or expose any part
of the body to an antenna or open RF generating tube or circuit or RF transmission system while
energized. Monitor the tube and RF system for RF radiation leakage at regular intervals and after
servicing.
HOT SURFACES –
The power components in the transmitter are cooled by forced-air and natural convection. When
handling any components of the transmitter after it has been in operation, caution must always be
taken to ensure that the component is cool enough to handle without injury.