Lexicon LDD-1 User manual

LDD-1
AC-3/RF Demodulator User Guide

Unpacking and Inspection
Save all packing materials in case you ever need to ship the unit. Thoroughly inspect the unit and packing materials for signs of damage.
Report any shipment damage to the carrier at once; report equipment malfunction to your dealer.
Precautions
Save these instructions for later use.
Follow all instructions and warnings marked on the unit.
Always use with the correct line voltage. Refer to the manufacturer's operating instructions for power requirements. Be advised that different operating voltages may require the
use of a different line cord and/or attachment plug.
Do not installthe unit in an unventilated rack, ordirectly above heat producing equipment such as power amplifiers. Observe the maximum ambient operating temperature listed
in the product specification.
Slots and openings on the case are provided for ventilation; to ensure reliable operation and prevent it from overheating, these openings must not be blocked or covered. Never
push objects of any kind through any of the ventilation slots. Never spill a liquid of any kind on the unit.
This product is equipped with a 3-wire grounding type plug. This is a safety feature and should not be defeated.
To prevent shock or fire hazard, do not expose the unit to rain or moisture, or operate it where it will be exposed to water.
Do not attempt to operate the unit if it has been dropped, damaged, exposed to liquids, or if it exhibits a distinct change in performance indicating the need for service.
This unit should only be opened by qualified service personnel. Removing covers will expose you to hazardous voltages.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
This triangle, which appears on your
component, alerts you to the pres-
enceofuninsulated,dangerousvolt-
age inside the enclosure... voltage
that may be sufficient to constitute a
risk of shock.
Thistriangle,whichappearsonyour
component, alerts you to important
operating andmaintenanceinstruc-
tions in this accompanying litera-
ture.
Acknowledgements
The CP and DC Series are manufactured under license from Dolby Laboratories Licensing Corporation. Additionally licensed under one or more of the following patents: U.S.
numbers 3,632,886, 3,746,792 and 3,959,590; Canadian numbers 1,004,603 and 1,037,877. "Dolby" and the double-D symbol are trademarks of Dolby Laboratories Licensing
Corporation.
Copyright 1997 Lexicon, Inc.
All Rights Reserved. Lexicon Part # 070-11659 Rev 1
Lexicon Inc. • 3 Oak Park • Bedford MA 01730-1441
Telephone [phone] • Fax [phone]

Congratulations on your purchase of the Lexicon LDD-1. The LDD-1 is designed to interface between
a laser disc player (with an AC-3/RF output), and any Dolby Digital decoder which accepts a standard
AC-3signal(likeour DC-1). Because“AC-3ready” laserdisc playersuseaseparateRadio Frequency
(RF) modulated output to carry the Dolby Digital information, special considerations must be made.
Whilethis typeof transmissionworksperfectlywell,our engineerswererightfullyreluctantto injectline-
level RF directly into the meticulously designed DC-1. The solution is the LDD-1.
The LDD-1 keeps potential RF interference away from the sensitive preamp/processor stage while
providing highly useful improvements in AC-3 signal quality. By placing the requisite demodulation
circuitry in its own enclosure with dedicated power supplies and grounding, the potential to degrade
digital-to-analog conversion and analog audio signals within the preamp/processor is eliminated.
The LDD-1 incorporates fully automated “intelligent” switching between S/PDIF and AC-3/RF inputs,
meaning that any laser disc will be decoded to its maximum inherent quality. A low voltage “turn on
trigger”input andoutput areincludedforinterconnectionto theLexicon DC-1andNTSeriesAmplifiers.
The stringently designed outboard power supply ensures maximum signal purity.
We have designedthis manual toprovide a briefoverviewof the demodulator,as wellas to providethe
information necessary for safe installationand operation. We trustthat the time youinvest in reviewing
these brief instructions will be rewarded by the best possible performance and longevity of your
equipment.
Introduction
LDD-1
AC-3/RF Demodulator User Guide
1

LOCK
This LED will light whenever the unit
sensesanAC-3/RFsignal.Whennosuch
signal is present, the LED will remain off,
and the INPUT SELECT LED will light.
POWER
This LED willlight whenever power to
the unit is supplied and enabled.
INPUT SELECT
2-position switch for selection of the type of NON-AC-3/
RF digital output you are using from your laser disc
player.
NOTE: When power is off, the LDD-1 automatically
outputs the COAXial digital input. Front Panel
LD OPTIMIZATION
3-position switch which minimizes signal errors, pro-
viding optimal timing for specific brands of laser disc
players.
Recommended Settings
High Panasonic, Pioneer CLD-97 (MSB modified
version), Runco
Low Denon, Enlightened Audio Designs, Pioneer
LD-S2 (MSB modified version)
Normal Marantz, Mitsubishi, McIntosh, MSB, Theta,
Pioneer (including Elite), Yamaha
2
2

OUTPUT
ConnectthisS/PDIFoutputtoDC-1digitalinputCOAX1
with a 75Ωcoaxial cable.
POWER
Connect the AC adapter here. Use onlythe supplied Lexicon
MSA AC adapter.
INPUT
Connect a 5-pin DIN cord (not supplied)
from this input to the DC-1 PWR CTL
Output.Thisallowsthe LDD-1 to poweron
and off withthe DC-1. If nothing is hooked
up here, the unit will turn on whenever the
AC adapter is supplied power. This set-up
allows use of a switched outlet or continu-
ous power. (As power consumption and
heat generation are both minimal, this will
not harm the LDD-1.)
S/PDIF INPUTS
Connectthisinputtothelaserdiscplayer’sNON-AC-3digital
output using the appropriate 75Ωcoaxial cable.
Becauseyoucanswitchbetweenthese inputsfrom thefront
panel, you may use both; which gives you an extra digital
input.
LOOP THRU
Allowsthehook-upand powercycling of addi-
tional components such as the Lexicon NT
Series of power amplifiers. Refer to the DIN
configuration diagram below.
RF IN
Connect this input to the laserdisc player’s RF/AC-3
output with a 75Ωcoaxial cable. Keep this cable as
short as possible to minimize RF interference.
Connections between the LDD-1 and associated
equipment should be made with all units UNPLUGGED! Rear Panel
1 = Ground
2 = Ground
3 = Power On (constant
when the DC-1 is On)
4 = Unused
5 = Trigger(programmable)
3

4

Setup
The LDD-1 chassis is barely four inches deep to allow it to be positioned adjacent to an AC-3-capable
player’s RF output. This minimizes the requiredRF-signal cable length to reduce any RFinterference.
As the unit uses automated switching, and draws very little power, you can literally set it and forget it.
To set up the LDD-1:
• Connect a 75Ωcoaxial cable between the LDD-1 rear panel RF (AC-3) input and the laser disc
player's RF/AC-3 output. Keep this cable as short as possible to minimize RF interference.
• Connect a 75Ωcoaxial (or optical) cable between the LDD-1 S/PDIF input and the laser disc
player's digital output.
• Connecta75Ωcoaxialcablebetwenthe LDD-1S/PDIFoutputandtheDC-1COAX1digitalinput.
•Recommended:Connecta5-pinDINcord (notsupplied)betweentheLDD-1 PWRCTLinputand
the DC-1 PWR CTL output. This allows the LDD-1 to power on and off with the DC-1. If this
connection is not made, the LDD-1 will turn on whenever its AC adapter is supplied power.
•Optional: Connect anyadditional components which allow remoteturn on(such as Lexicon's NT
Series of power amplifiers) to the LDD-1 rear panel PWR CTL (LOOP THRU) connector.
• Connect the AC adapter provided to the POWER jack.
Once the LDD-1 is properly connected, set the front panel INPUT SELECT switch for theappropriate
type of NON-AC-3/RF digital output you are using on your laser disc player. (Most laser disc players
haveonlyone.)SettheLDOPTIMIZATIONswitchaccordingtothechartprovidedonpage2.Onceyou
have completed the connections and setting of the front panel switches, all functions are performed
automatically. LEDs on the front panel are provided to identify the operational state.
TheLDD-1requiresnomaintenance. However,itisgoodelectricalpracticetocleanallconnectorsonce
a year. Clean the exterior surfaces of the unit with a soft, lint-free cloth, dampened with warm water. Maintenance
5

Specifications
Lexicon Part # 070-11659 Rev 1 Printed in U.S.A.
Lexicon Inc.
3 Oak Park
Bedford MA 01730-1441
Telephone[phone]
Fax [phone]
Inputs 2: 1AC-3/RF via COAX; 2 Digital (1 COAX; 1 Optical)
Outputs One (1) Digital via COAX
Optimization 3-position toggle switch, decoder pulse settings
Controls and Indicators LEDs indicate operational status
Toggle switches for: LD Optimization: High, Low, Normal; Input Select: Optical, COAX
Connectors Inputs: 4: 2 RCA (COAX); 1 TOSLINK (Optical); 1 5-pin DIN (PWR CTL)
Outputs: 2: 1 RCA (COAX); 1 5-pin DIN (PWR CTL Thru)
Power connector: 2.5mm, 9VAC, 1A
General Dimensions: 17.0"X x 1.75"H x 4"D
Weight: 2.4 lbs net; 4.4 lbs shipping
Power Requirements: 120VAC, 60Hz or 230VAC, 50Hz. Use Lexicon MSA AC Power Adapter.
Rack mount adapters are available through your Lexicon dealer.
All specifications subject to change without notice.