Terminal Connections; Mounting Requirements; General Considerations - Hitachi ATT-20 Installation, Operation, Troubleshooting

2.4. Terminal Connections

AAR type terminals are located on the top of the unit for making external connections.
Refer to Table 2-1 for terminal assignments.
Internal wiring is accessed through a hole with a grommet around it in the faceplate.
Also located on the faceplate is an access hole which is intended for setting transmitter
gain. This is a simple adjustment and can be accomplished with a screwdriver.

2.5. Mounting Requirements

A convenient mounting bracket, which is an integral part of the case, provides four holes
spaced 2-1/4 x 8-1/2 apart to facilitate wall, shelf or rack mounting.

2.6. General Considerations

• Track leads to the transmitter and receiver must be a #9 AWG or heavier twisted
pair.
• Power supply must be 9.8 - 15.2 VDC and capable of supplying 1 ampere. A
surge ripple filter (STS USA Part No. N451590-0301) must be used between any
supply and the ATT-20. Power supply ripples must not exceed 1.0 Vpp.
• Use higher frequency units when less ring-by is desired.
• Provide lightning protection per Section 2.9.
• The relay recommended to be used with ATT-20 is a vital PN-150B, STS USA
No. N322500-701, 400 ohm, plug-in type.
Copyright 2019
Table 2-1. Terminal Assignments
Terminal No.
1 + Battery
2 - Battery
3 Transmitter Lead
4 Transmitter Lead
5 Receiver Lead
6 Receiver Lead
7 + Relay
8 - Relay
SM 6299 Rev. 3, March 2019
ATT-20 Audio Track Transceiver
Description
2-3