Technical data

www.asti-usa.com ASTi DACS: Operation & Maintenance Manual (Version 4, Rev. B.1)

All RIUs ship with a basic user guide which provides speciﬁcations, conﬁguration information

and other general information speciﬁc to the version of RIU shipped. Current and legacy RIU

manuals may also be downloaded from the ASTi website:

http://www.asti-usa.com/

Audio Inputs:

Audio input preamp gain can be conﬁgured from 0dB to 60dB via jumpers on the

RIU circuit card. Factory setting is a gain of 40dB. Input voltage should not exceed 4.5Vp-p for a

gain setting of 0. For other settings, voltage levels should not exceed 4.5Vp-p after the gain has

been applied.

Phantom power capability is available on the RIU Version 4.1 and later. The phantom power capa-

bility is very limited, providing only 10VDC across the microphone lines.

See appendix A or consult the RIU user guide shipped with each RIU for additional interface and

conﬁguration information.

Audio Outputs:

Version 4.1 and later RIUs have a 4.5Vp-p output drive capability into an 8

bridged load.

Digital I/O:

A general purpose digital input and digital output is provided with each audio chan-

nel. The digital input is convenient for sensing PTT (Press-To-Talk) switch states directly. The

digital output is convenient for driving PTT inputs on actual communications equipment or for

driving small LEDs.

Serial Ports:

Two serial ports are provided for direct connection of Hand Held Terminals, com-

munication control panels, simulated radio panels, etc. Serial ports are active in version D RIUs

and later only. Operation also requires the installation of Model Builder version 4.0 or higher.

The serial ports effectively act as an I/O interface for whatever panel or control unit is connected.

Panel state information is read by the RIU and returned to the main DACS unit. This information

is then typically passed on to a dynamic link library (DLL) for processing. The DLL, running a

custom developed state machine model for the panel, processes the data and returns additional

state parameters for use either by the sound and communications models or the panel itself.

Packaging and Layout:

The RIU is generally provided in a standard enclosure. Unpackaged, cir-

cuit board only versions and custom enclosures can also be provided by special request. The stan-

dard packaged unit is approximately 5.5” wide x 1.5” high x 8.5” deep. See appendix B for a

mechanical layout of the RIU standard enclosure.

Audio and digital I/O interface is via a set of female D sub 9 connectors located on one of the end

plates. Individual channels are marked A-D. Located on the opposite end panel are two RJ-45

connectors for connection of the TDM link cable.

Two RJ-12 connectors are also located on the end panel for interface to the two serial ports.

A red power/error light and a green sync indicator light are also located on the end plate to pro-

vide status information.

A rack mount kit is available for mounting up to three RIUs in a 19 inch rack with 1U of rack

space.