Professional Wireless System
4. R33 RECEIVER FRONT PANEL
(see figure 3)
The green LED
RF indicator light
lights when there is sufficient signal from the M33 transmitter for good operation.
Internal circuitry detects both signal levels and external interference levels and decides if the transmitted signal has
enough strength and is clean enough for satisfactory operation. If the signal is not good enough, then the green RF
indicator light turns off and the audio is shut off or “squelched”. Some wireless systems require that the transmitter be
on at all times to prevent the receiver from picking up noise or interference. This is not necessary with the PER
FORMER due to the superior operation of the squelch circuit. The squelch circuit operates automatically and, unlike
some other systems, does not require level adjustments for different environments.
The red LED
PWR indicator light
turns on when the R33 is turned on and has power available.
The green LED
MOD LEVEL
indicator light varies in brightness with the audio level from the transmitter. It is not
affected by the volume control or the mute switch on the R33. The indicator operates over a very wide range (-45 to -65
dB) and commonly will light on just background room noise.
The red
MOD LEVEL indicator light
will turn on when the audio signal levels are greater than a preset level (-6 dB).
This indicator is similar to the distortion or clipping indicator used on some control boards and amplifiers. However, on
this system there is considerably more headroom (16dB) due to the compandor circuitry and soft compressor circuitry
built into the transmitter. It is normal for this indicator to flash occasionally during operation. Section 7 will cover in
more detail the use of the MOD LEVEL lights in setting up the system.
The
OFF-MUTE-ON switch
has a center position that is used to mute (shut off) the audio outputs without affecting the
indicator lamps or changing the level setting. When turning the system on, pause in the MUTE position for a few
seconds to allow the circuitry to stabilize. This prevents thumps in the sound system. The MUTE position is also used
during setup adjustments to prevent feedback or noise as the transmitter gain is adjusted. The MUTE position can also
be used to test the operation of the system without sending a signal to the mixing console.
The
VOLUME control
is an attenuator (output pad) which controls the mic level output and the instrument output on
the back of the R33. It does not control the tape output and does not affect the MOD LEVEL indicator lights. The
setting of the VOLUME control does not affect noise or distortion levels since it is an output attenuator. The most
common setting is fully clockwise at 0 dB. The VOLUME control is used to adjust R33 output levels into your mixing
console or instrument amplifier to match the input levels from other instruments or microphones.
Rio Rancho, NM – USA
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