Table Of Contents; Introduction; Dsp-Controlled Input Limiter - Lectrosonics DCHT Instruction Manual

DCHT

Table of Contents

Introduction ............................................................................ 2
DSP-controlled Input Limiter ................................................ 2
DCHT Block Diagram ........................................................... 3
Features and Functions ........................................................ 4
Optional Battery Eliminator .................................................. 4
Whip Antennas ..................................................................... 4
Battery Status LED Indicator ............................................... 5
Belt Clips .............................................................................. 5
IR (infrared) Port .................................................................. 5
Status LED ........................................................................... 5
Battery Installation ................................................................ 5
Powering On and Off ............................................................. 6
Powering On in Operating Mode .......................................... 6
Powering On in Standby Mode ............................................ 6
Powering Off ........................................................................ 6
Power Button Menu ............................................................... 6
Entering the Power Menu ..................................................... 6
LCD Menu Map ....................................................................... 7
Main Menu and Setup Screen Details .................................. 8
Entering the Main Menu ....................................................... 8
Main Window Indicators ...................................................... 8
Connecting the Signal Source ............................................. 8
Adjusting the Input Gain for Analog Inputs .......................... 8
Selecting Frequency ............................................................ 9
Selecting M2R Receiver Functions ...................................... 9
Selecting Programmable Switch Functions.......................... 10
Selecting the Low Frequency Roll-off .................................. 10
Selecting StMode (stereo mode) ......................................... 10
Selecting Input Type ............................................................. 10
Selecting Input Configuration ............................................... 10
Selecting Battery Type ......................................................... 11
BatTime ................................................................................ 11
Enable/Disable Remote Control Function ............................ 11
Setting Transmitter Output Power ........................................ 11
Locking/Unlocking Changes to Settings............................... 11
Restoring Default Settings ................................................... 11
12
Microphone Cable Termination
for Non-Lectrosonics Microphones .............................. 13
Firmware Update ................................................................... 14
Accessories ........................................................................... 16
Troubleshooting ..................................................................... 17
Specifications ........................................................................ 18
Service and Repair ................................................................ 19
Returning Units for Repair ................................................... 19
Canada ISED Notice
This device operates on a no-protection, no-interference basis. Should the user seek to obtain
protection from other radio services operating in the same TV bands, a radio licence is required.
For further details, consult Innovation, Science and Economic Development Canada's document
Client Procedures Circular CPC-2-1-28,
Radio Apparatus in the TV bands.
2

Introduction

The DCHT transmitter is designed to work with a com-
panion receiver (such as the Lectrosonics M2R, part
of the Duet IEM system) as an audio relay between an
audio production bag or cart and a camera or other au-
dio device. The 6-pin input jack accepts two mic or line
level analog signals or AES digital signals from external
sources with a variety of adapter cables. Analog in-
puts can be linked for the same gain when used with a
stereo source, or operate independently with individual
settings.
This third generation digital design features specially
developed, high efficiency digital circuitry for extended
operating time on two AA batteries. The transmitter can
tune in coarse or fine steps across the UHF television
band from 470.100 to 607.950 MHz, with a selectable
output power of 10, 25 or 50 mW.
Studio quality audio performance is assured by high
quality components in the preamp, wide range input
gain adjustment and DSP-controlled limiting. and
settings are included for any lavaliere microphone,
dynamic microphones and line level inputs. Input gain
is adjustable over a 51 dB range in 1 dB steps to allow
a precise match to the input signal level, to maximize
dynamic range and signal to noise ratio.
A separate switch is provided on the top panel that can
be configured as mute, power or bypass.
The housing is constructed of solid machined aluminum
for lasting ruggedness. The exterior is finished with an
ultra hard, dark electroless nickel finish called ebENi.
Firmware updates are made through a side panel micro
USB port.

DSP-controlled Input Limiter

The transmitter employs a DSP-controlled analog audio
limiter prior to the analog-to-digital converter. The limiter
has a range greater than 30 dB for excellent overload
protection. A dual release envelope makes the limiter
acoustically transparent while maintaining low distor-
tion. It can be thought of as two limiters in series, con-
nected as a fast attack and release limiter followed by
a slow attack and release limiter. The limiter recovers
quickly from brief transients, so that its action is hidden
from the listener, but recovers slowly from sustained
high levels to keep audio distortion low and preserve
short term dynamic changes in the audio level.
Voluntary Licensing of Licence-Exempt_Low-Power
LECTROSONICS, INC.