Northern Airborne Technology 250 - Manual (Page 15)

EQUIPMENT MANUAL 250-16-1
250/250-16-1 Page 6
3.0 INSTALLATION PROCEDURES, WIRING DIAGRAMS, AND LIMITATIONS
3.1 PHYSICAL
Installation dimensions are shown on the Model 250 outline on Figure 1. The amplifier may be
mounted to a metal or plastic surface, but it is necessary to ground the case to the metal aircraft
structure. When mounting to a plastic surface, use a grounding strap. The case is finished with
an electrically conductive film so it is not necessary to remove the film for electrical bonding.
The Model 250 may be mounted in any position. No shock or vibration isolators are required.
3.2 ELECTRICAL
Connections to the Model 250 are made through two "D" subminiature connectors. The mating
connectors are manufactured by Positronics Industries, Inc. and have part numbers for the
complete connector assemblies, which are:
Connector
Positronics Part No.
P40 (25-pin)
SD25F1OJVLO
P50 (37-pin) SD37F1OJVLO
Numerical pin identification is shown on Table 1. The wiring diagram is shown on Figure 2.
Shielded wire must be used where indicated on the diagrams. AWG 24-26 size wire should be
used for all connections except those to the input power, power ground, and speaker amplifier
outputs where AWG 20 (min.) size should be used.
The control switches shown will switch low current loads and should have a DC rating of 28 VDC.
Typical switches for this application include Alco MTA series.