instantaneously to short-duration “spikes” and other transient peaks in voice energy.
These peaks can cause the instantaneous peak deviation of the transmitter to reach
values of about 3 dB above the normal steady-state maximum. The R-27 will
accommodate these brief transients without distortion due to its ability to provide in
excess of +6 dBm of output without clipping.
The battery-power indicator stays on, provided that battery life is good. As soon as the
battery voltage drops to an unacceptable level, the PWR LED turns off. When this
occurs, the battery has less than an hour of life remaining.
Power Switch (PWR): On/off switch for the receiver. The current drain is 45 mA with
the headphone monitor control switch set to “off”. In the “on” position the current
increases by about 10%. The current can increase even further, depending on the load
presented to the monitor jack and the audio level of the receiver.
Monitor Level Adjust (MON): The only adjustment on the front panel; it is used to
adjust the audio level to the monitor stereo jack. This control incorporates a monitor
on/off switch which can turn off the audio to the jack by turning the control fully
counter-clockwise until a click is felt. In this position, the power drain to the battery is
reduced.
Audio Level Adjust: Located on the rear panel, it adjusts the audio output of the
receiver. This control has approximately 46 dB of operating range and has an audio
taper.
Connectors
Antenna (ANT): Front-panel BNC connector for use with the antenna supplied.
XLR Audio Output: Rear-panel-mounted, full-sized, three-pin, male, XLR connector
which provides mic-level balanced audio output from the receiver.
Monitor Jack (MON): Front-panel, miniature, stereo, female headphone connector
which supplies audio for low-impedance headsets such as the type used on miniature
inexpensive portable receivers.
Operating Instructions
(1) Install a 9-volt alkaline battery in the R-27 receiver by sliding the battery door open
on the rear panel. Be sure to observe the polarity marking inside of the battery
compartment near the compartment door. The receiver is reverse-polarity protected and
cannot be damaged by incorrect battery insertion, but the unit may fail to operate and
the battery life greatly shortened if the battery is not correctly installed. If the battery is
not correctly installed, the battery-compartment door will not close properly. Do not
attempt to force the door closed; instead, check and correct the battery polarity.
(2) Connect the receiver antenna (“rubber duckie” supplied). A right-angle adapter is
provided for use with the “rubber duckie”, should one be needed.
A vertical orientation is recommended; however, there will be no great difference in
performance if horizontal mounting is necessary. In either case, the antenna should be
positioned away from the chassis of the receiver (or other metallic objects such as
cameras, sound carts, etc.).
4
R-27 Portable
