ACCESS/A A711 L-Series Installation Manual 09RE416
Technisonic Industries Ltd. Copyright 1996, 1997, 2010, 2011 BY TiL ALL RIGHTS RESERVED Page 1-1
SECTION 1
GENERAL DESCRIPTION
1.1
INTRODUCTION
This publication provides operating and installation information on the Model A711 L-series,
ACCESS/A Audio Controls manufactured by Technisonic Industries Limited. For convenience, it
is referred to as the “A711L” in the manual. This unit is designed to provide high performance
cockpit audio control in high noise installations. The unit is plug and pin compatible with the
ACCESS/A family format, to allow fleet wide compatibility with all ACCESS/A installations, with
the following limitations: The A711L has its extra functions assigned to the “Alerting”
connector, and can also have 3-tone alerting as an internal option. These connections are slightly
different than a standard A710/711 unit, and to prevent any airframe problems, the alerting
connector has different locks on the A711L, to make it impossible to connect it to an airframe
wired for default A710/711 functions. If an existing installation had no alerting connector wiring,
then it can be used without difficulty, but note the installation issues regarding annunciator
dimming. The A711L comes ONLY in a 28V panel backlight configuration.
1.2
DESCRIPTION
This high power audio controller delivers at least 332 mW of audio into 150 ohms at less than 2%
total distortion to the pilot and co-pilot positions simultaneously. It can deliver lower output powers
into 300 and 600 ohm headsets. The pilot’s position may also be internally strapped to interface
with 8-20 ohm headsets at the same power level. Push-button transmit selector switches allow
immediate selection of any of the seven supported aircraft communications transceivers and a PA
amplifiers, while additional push-button audio input selector switches allow selection of any or all
of the supported transceiver’s receive audio lines. In addition, a switched (and adjustable) input is
provided for special functions such as Cross-Sidetone (CST), a Nav Aid, or a Music feed.
ACCESS/A systems have auto-RX switching when a transmitter is selected, to reduce pilot
workload and avoid operational problems.
The A711L has front panel selectable and adjustable VOX, LIVE or KEYED intercom (ICS)
functions. An EMERGENCY mode push-button switch (switch and LED turn red-orange when
activated) provides "straight through" or “fail-passive” transmit and receive audio for the pilot on
the selected communications channel. This switch also provides an implicit pilot ISOLATION
function, and allows the pilot to isolate himself from the co-pilot (and the ICS system), so that he
may access different communications from the other users supported by this panel (in essence,
an emergency link to the selected transceiver only). In the NORMAL position (switch turns black
& LED green), the pilot's audio is provided as selected by all of the panel controls, and is part of
the ICS system. Separate RX and ICS volume controls are provided on the panel along with an
ICS VOX threshold control. These units can also provide ICS support and boom mic TX support
for a complete aircraft crew, including the pilot, co-pilot, and up to 4-6 additional passengers.
