Lectrosonics Inc HHAA1 사용자 설명서

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HHa
LECTROSONICS, INC.
4
General Technical Description
Introduction
The HHa handheld transmitter uses state-of-the-art 
Digital Hybrid Wireless
® 
wireless technology, select-
able output power and a versatile microphone capsule 
mounting system to meet the needs of audio profes-
sionals and vocalists.
The compandor-free Digital Hybrid audio chain pre-
serves the quality of the selected microphone capsule 
and delivers it to the sound and recording system 
without coloration. This superb audio performance and 
highly reliable RF transmission makes it ideally suited 
for high end stage and studio production.
Digital Signal Processor
The DSP encodes the digitized audio from the A-D 
converter and adds an ultrasonic pilot tone to control 
the receiver’s squelch in systems that use pilot tone. It 
also controls the input limiter and audio metering.
Compatibility Modes
The transmitter was designed to operate with Lec-
trosonics Digital Hybrid Wireless
®
 receivers and will 
yield the best performance when doing so. Due to 
the flexibility of digital signal processing, however, the 
transmitter is also able to operate with Lectrosonics 
200 Series, Lectrosonics 100 Series, IFB and certain 
non-Lectrosonics analog receivers in special compat-
ibility modes.  (Contact the Lectrosonics Sales Depart-
ment for a complete list of compatible receivers.)
Digital Hybrid Wireless
®
 Technology 
All wireless links suffer from channel noise to some 
degree and all wireless microphone systems seek to 
minimize the impact of that noise on the desired signal.  
Conventional analog systems use compandors to 
increase the signal to noise ratio, at the cost of distor-
tion artifacts. Wholly digital systems defeat the noise 
by sending the audio information in digital form, at 
the cost of some combination of power, bandwidth or 
channel count.
The Lectrosonics Digital Hybrid Wireless
®
 system over-
comes channel noise by digitally encoding the audio 
in the transmitter and decoding it in the receiver, yet 
still sending the encoded information via an analog FM 
wireless link. This proprietary algorithm is not a digital 
implementation of an analog compandor. Instead, it 
is a technique that can be accomplished only in the 
digital domain, even though the inputs and outputs are 
analog signals.  
Because it uses an analog FM link, the system enjoys 
all the benefits of conventional FM wireless systems, 
such as excellent range, efficient use of RF spectrum, 
and long battery life.  However, unlike conventional FM 
systems, the design has eliminated the analog com-
pandor and its artifacts.
Wide Deviation
±75 kHz deviation is used in the Digital Hybrid and 200 
Series compatibility modes to dramatically improve 
the capture ratio, signal to noise ratio and dynamic 
range of the wireless system. This, in conjunction with 
accurate input gain adjustment, produces outstanding 
audio quality that rivals a hard wired connection.
Mic 
capsule
Bias 5V
+7V
Input 
Amp
Interface
Shunt 
Limiter
MENU/SEL
BACK
MUTE
POWER
Reference 
Crystal
Reference 
Crystal
3 V 
Battery
Variable 
Switching 
Power 
Supply
Hi.Lo 
Pass 
Filter
Digital 
Pot
Audio 
Level
Phantom 
Power
Audio
A-D 
Converter
11001001
D-A 
Converter
11001001
Control P
anel
Microprocessor
Voltage 
Controlled 
Oscillator
Final 
Amplifier
Filter 
Amp
Encoded Audio 
and Pilot Tone
Bicolor 
Modulation 
LEDs
Switching 
Power 
Supply
Digital Signal Processor
Phase Locked Loop
LCD