User Guide

Model฀74/75฀User฀Guide฀ Issue฀3,฀November฀2016฀
Studio฀Technologies,฀Inc.฀ Page฀15
for Surround
฀Pin฀ Signal฀ Direction
฀ 1฀ Power฀Supply฀Common฀ 74฀to/from฀75
฀ 2฀ +15฀Volts฀DC฀ 74฀to฀75
฀ 3฀ Data฀(MIDI฀System-Exclusive)฀ 75฀to฀74฀
฀ 4฀ Data฀Common฀ 74฀to/from฀75
฀ 5฀ Remote฀Mute฀All฀ 74฀to฀75฀(Note฀2)
฀ 6฀ Remote฀Dim฀ 74฀to฀75฀(Note฀2)
฀ 7฀ Remote฀Talkback฀ 74฀to฀75฀(Note฀2)
฀ 8฀ Remote฀Input฀Select฀ 74฀to฀75฀(Note฀2)
฀ 9฀ Talkback฀Mic฀Audio฀ 75฀to฀74
Notes:฀ 1)฀Connector฀types฀on฀Model฀74฀and฀Model฀75฀are฀฀
฀ 9-pin฀female฀D-subminiature฀(DE-9F).฀Connectors฀use฀฀
฀ 4-40฀threaded฀inserts฀for฀locking฀with฀mating฀plug฀฀
฀ (DE-9M).
฀ 2)฀Remote฀control฀sources฀connect฀to฀D-sub฀on฀฀
฀ Model฀74,฀then฀passively฀route฀to฀Model฀75฀via฀฀
฀ 74/75฀interface฀D-sub.
Figure฀11.฀Connections฀between฀Model฀74฀and฀
Model฀75
Model฀75฀route฀the฀remote฀control฀signals฀
to฀the฀actual฀input฀circuitry.
Connecting฀the฀Model฀74฀to฀
the฀Model฀75
A฀cable฀with฀9-pin฀D-sub฀plugs฀(DE-9M)฀on฀
each฀end฀is฀used฀to฀interconnect฀the฀Model฀
74฀Central฀Controller฀with฀the฀Model฀75฀
Control฀Console.฀A฀cable,฀approximately฀
20-feet฀(6.1-meters)฀long,฀is฀provided฀with฀
each฀system.฀The฀connector฀labeled฀To/
From฀Control฀Console฀on฀the฀back฀panel฀
of฀the฀Model฀74฀is฀used฀to฀connect฀to฀the฀
Model฀75.
Should฀a฀cable฀of฀different฀length฀be฀re-
quired,฀it฀should฀be฀wired฀in฀a฀one-to-one฀
fashion฀for฀all฀nine฀pins.฀Pin฀1฀serves฀as฀
signal฀common฀and฀must฀be฀connected฀
at฀both฀ends.฀A฀shield฀connection฀for฀the฀
cable฀should฀also฀be฀connected฀to฀pin฀1฀on฀
the฀Model฀74’s฀end.฀For฀best฀performance฀
the฀cable฀generally฀should฀not฀exceed฀฀
50฀feet฀(15.3฀meters)฀in฀length.
The฀reality฀is฀that฀a฀cable฀longer฀in฀length฀
than฀50฀feet฀should฀work฀correctly,฀as฀long฀
as฀an฀excellent-quality฀cable฀is฀utilized.฀We฀
define฀“excellent”฀as฀extensive฀shielding฀
along฀with฀very฀low฀capacitance.฀The฀low฀
cable฀capacitance฀is฀important฀as฀it฀limits฀
the฀amount฀of฀data-signal฀waveform฀distor-
tion.฀As฀far฀as฀determining฀an฀actual฀maxi-
mum฀length,฀just฀test฀and฀see฀how฀far฀away฀
you฀can฀go—if฀it฀works,฀it฀works!฀A฀termina-
tion฀resistor฀connected฀from฀pin฀3฀to฀pin฀4฀
at฀the฀Model฀75’s฀end฀of฀the฀interconnecting฀
cable฀may฀help฀to฀support฀a฀longer฀cable฀
“run.”฀The฀value฀of฀the฀termination฀resistor฀
should฀be฀in฀the฀range฀of฀3.3฀k฀(3300)฀to฀
10฀k฀(10000)฀ohms.฀A฀commonly฀available฀
¼-watt,฀5%฀tolerance฀resistor฀is฀perfectly฀
acceptable.
Infrared฀Remote฀Control฀Input
An฀infrared฀(IR)฀receiver฀module฀can฀be฀
directly฀connected฀to฀the฀Model฀74.฀This฀
allows,฀with฀an฀appropriate฀IR฀transmitter,฀
wireless฀activation฀of฀the฀talkback฀func-
tion.฀The฀IR฀receiver฀connects฀to฀the฀Model฀
74฀using฀a฀3.5฀millimeter฀3-conductor฀jack฀
which฀is฀located฀on฀the฀back฀panel.฀The฀jack฀
complies฀with฀the฀standard฀convention฀for฀
IR฀receiver฀modules:฀data฀on฀the฀tip฀lead,฀
ground฀on฀the฀ring฀lead,฀and฀12฀volts฀DC฀฀
on฀the฀sleeve฀lead.฀Compatible฀modules฀
are฀available฀from฀a฀number฀of฀companies.฀
As฀an฀example,฀the฀Xantech®฀291-80฀looks฀
nice฀and฀works฀adequately.฀For฀excellent฀
performance฀under฀compact฀florescent฀light-
ing฀conditions฀the฀Russound®฀SaphIR฀860฀
Phantom฀has฀proven฀its฀worth.
For฀correct฀wireless฀talkback฀operation฀
selecting฀and฀programming฀a฀compatible฀
transmitter฀is฀necessary.฀Refer฀to฀the฀฀
Configuration฀section฀of฀this฀user฀guide฀฀
for฀details.