Lectrosonics AV 62, Operating Instructions Manual

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GENERAL TECHNICAL DESCRIPTION
The AV62 uses a straightforward analog signal path to provide excellent audio performance. Enhanced signal routing and
mixing capability make the AV62 far more versatile than a simple routing switcher. For example, line level sources may be
mixed together for multi-media presentations.
Figure 1 shows the simplified block diagram of the AV62. Each line level input has individually controllable input gain. The
individual left and right line inputs are mixed after the input gain control. The left and right signals then pass through a
stereo tone control. From there, the signals are distributed to the various outputs according to the user’s setup.
The microphone preamp is a low-noise discrete design, which is extensively RF protected. The preamp has three gain
settings. The 0dB setting allows an input to accept line level signals, while the +30dB and +50dB gain settings accommo­
date both low and high sensitivity microphones. 15V Phantom power is provided for each channel, and is always active.
The two mic inputs have individual level controls. The post level control signals are summed, and passed on to the tone
control circuitry. From there, the signals are distributed to the various outputs according to the user’s setup.
Six Line In Select pushbuttons allow line level audio sources to be selected when the AV62 is in the Local mode. The AV62
may be programmed to allow only one audio source at a time or any number of audio sources. Six Remote Line/Memory
Select terminals are available on the rear panel 9 pin D-Sub connector that replicate the function of the front panel
pushbuttons for remote control applications. In addition, both the Program and Mono output levels may be individually
remotely controlled using a 10K linear pot.
Signals from the Expansion In and Expansion Out connectors allow an AV62 to be combined with one or more AM8s if
more than 2 microphone inputs are necessary for the application. Special circuitry in the AV62 allows its microphone inputs
to function as automatic mics when combined with AM8s. In addition, a Mix Minus signal is available which allows easy
interfacing to the TH2 or other teleconferencing hybrids.
An RS-232 port is available to allow many of the functions of the AV62 to be controlled either by a computer or a dedicated
control system (such as the AMX or Crestron systems).
LINE IN 1L
(RCA JACK)
(RCA JACK)
LINE IN 1R
INPUT LEVEL 1
FROM CH 2L-6L
FROM CH 2R-6R
BASS TREBLE
MIC 1 IN+
MIC 1 IN­
MIC PREAMP GAIN
+50dB
+30dB
LINE
15dB MAX GAIN
10dB MAX
GAIN
LINE
+30dB
+50dB
MIC PREAMP GAIN
MIC 2 IN­
MIC 2 IN+
TREBLE
BASS
+15V PHANTOM PWR
RF SUPPRESSION
+15V PHANTOM PWR
RF SUPPRESSION
MIC 2 LEVEL
MIC 1 LEVEL
LEFT AUDIO
RIGHT AUDIO
BALANCE
LIMITER
LIMITER
MONO LEVEL
LED
LIMIT
EXPANSION
IN
MAIN IN
MIX MINUS OUT
AUTO MIX LOG IN
AUTO MIX LOG OUT
1
2
3
4
6dB GAIN
6dB GAIN
6dB GAIN
LINE 1
LINE IN 1
LINE IN 2
LINE IN 3
LINE IN 4
LINE IN 5
LINE IN 6
PROGRAM VOLUME
MONO VOLUME
REMOTE
LINE/MEMORY
SELECT
68HC705 uC
MONO
AUDIO
STEREO
LEVEL/BALANCE
STEREO LIMITER
LEVEL
LIMITER LEVEL
LIMIT
LED
LED
LEFT
SUM
RIGHT
SUM
MONO
SUM
6dB GAIN
68HC705 uC
10dB MAX
GAIN
REMOTE VOLUME
CONTROL
LINE 2
LINE 3
LINE 4
LINE 5
LINE 6
LINK
LEFT OUT+
LEFT OUT­
RIGHT OUT+
RIGHT OUT­
MONO OUT+
MONO OUT-
Figure 1 - AV62 Block Diagram
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