ACE Communication Unit (ACU)

ACUs provide remote interfacing of audio and I/O peripherals over ASTi's Ethernet-based ACENet architecture. All audio and I/O is digitally distributed between ACUs and Target modeling platforms for maximum noise rejection and reliability. The ACU is desirable in situations that require enhanced control interfaces (discrete analog and digital interfaces) for example, sensing dual press-to-talk (PTT) inputs (radio and intercom) or where the operator interface is the ASTi 4-channel selector PTT.

A comprehensive overview of the ACU can be found in the Technical User Guide

General Specifications

Compatible with Telestra
Part Number ACU-1U-XX
Dimensions 12" length x 16.9" width x 1.72" height
Width with the rackmount kit is 19"
Weight Weight will vary depending on channel options. The maximum weight will not exceed 5.50 lbs including attached mounting brackets.
Power Source Individual power supply, included.
Power Consumption 15VDC, 3 A
Mean Time Between Failure (MTBF) 246,493 Hours (COTS)
122,999 Hours (Mil)

Audio Input/Output

Audio Input - Line Mode

Impedance 32 kΩ
Level +/- 2.25 Vp-p max. at 0 dB gain
Gain -20 to +20 dB software configurable
Microphone Power n/a
Total Harmonic Distortion (THD) + noise 0.045696 from 20 Hz to 20 kHz input
Typical: 0.040% at 1 kHz
Frequency Response +/- 3 dBv from 20 Hz to 20 kHz
Typical = 0.4 dBv at 20 Hz, -2.7 dBv at 20 kHz
Common Mode Rejection -78 dBv at 60 Hz, -56.4 dBv at 20 kHz
Typical = +/- 3.5 dBv from 20 Hz to 20 kHz
Noise at Unity Gain 89 dBv
Working Signal to Noise ratio at 20 dB headroom 89 dBv

Audio Input - Microphone Mode

Impedance 1.5 kΩ
Level +/- 2.2 Vp-p max. 0 dB gain
Gain 0 to +52 dB software configurable
Microphone Power Selectable T-Power at 13.8 VDC, current limited with 3.24 kΩ. Software enabled/disabled.
Total Harmonic Distortion (THD) + noise 0.064% from 20 Hz to 20 kHz
Typical: -0.048% at 1 kHz
Frequency Response +/- 3.5 dBv from 20 Hz to 20 kHz
Typical = +/- 3.5 dBv from 20 Hz to 20 kHz
Common Mode Rejection -67 dBv/td>
Noise at Unity Gain 60 dBv
Working Signal to Noise ratio at 20 dB headroom 60 dBv

WARNING! Do not plug a microphone requiring phantom power into an ACU device, this will cause damage to the microphone! If you are unsure of the difference between mic-power and phantom power, please contact the microphone manufacturer or ASTi before connecting equipment. Note: Most military headsets use mic-power

Audio Output

Impedance 12 Ω
Current 0.2125 A at 8 Ω
Level 1.7 VAC rms into 8 Ω
Power 1 lead: 0.36 W
2 leads: 0.5 W
Frequency Response +/- 3 dB from 20 Hz to 20 kHz
Total Harmonic Distortion(THD) + Noise < 0.07%
Max. Output Signal 10 Vpp

Memory Devices

This device works as a transportation mechanism, passing audio from one device to another until it reaches the headset or PC; this device does not store the audio.

Volatile Memory

Memory whose contents are lost when power is removed.

Type Size User Modifiable Function Process to Clear
Micro-controller Internal SRAM 4 KB No Used as RAM for an internal MCU Remove Power
Count to 30
Restore Power

Non-Volatile Memory

Memory whose contents are retained when power is removed.

Type Size User Modifiable Function Process to Clear
Micro-controller Internal Flash 128 KB Yes Firmware None
Micro-controller Internal EEPROM 8 KB Yes Store Settings None
Flash 4 Mb Yes Firmware None

Media

The ACU does not contain media storage capability (i.e., removable or non-removable disk drives, tape drives, memory cards, etc.)


Pinouts