Wulfsberg Electronics Division NTX403 User Manual

SM28 Rev. 2.10 NTX Series Remote Mount FM Transceivers Manual

Section 2.0 Installation

2.1 Introduction

Information in this section consists of: unpacking and inspection procedures, installation procedures, post-installation checks, and installation drawings.

2.2 Unpacking and Inspection

Unpack the equipment carefully, and locate the warranty card. Inspect the unit visually for damage due to shipping and report all such claims immediately to the carrier involved. Note that each unit should have the following:

- NTX Series Transceiver

- Warranty Card

- Release certification

Verify that all items are present before proceeding, and report any shortage immediately to your supplier.

Complete the warranty card information, and send it to NAT when the installation is complete. If you fail to complete the warranty card, the warranty will be activated on date of shipment from NAT.

2.3 Installation Procedures

2.3.1 Warnings ← IMPORTANT!

Do not bundle any lines from this unit with transmitter coax lines. Do not bundle any logic, audio, or DC power lines from this unit with 400 Hz synchro wiring or AC power lines. Do not position this unit next to any device with a strong alternating magnetic field such as an inverter or significant interference to operation will result. In all installations, use shielded cable exactly as shown

and ground as indicated.

Significant problems may result if these guidelines are not followed.

Oct 25, 2002 Page 2-1

ENG-FORM: 805-0104.DOT

PROPRIETARY AND CONFIDENTIAL TO NORTHERN AIRBORNE TECHNOLOGY LTD.

NTX Series Remote Mount FM Transceivers Manual SM28 Rev. 2.10

2.3.2 Cautions

Severe degradation of audio installations may result from incorrect wiring and shielding. This could cause much higher cross-talk, hum, and ground-loop interference.

2.3.3 Notes

For maximum resistance to low frequency interference, electrically ground the case of the NTX Series Transceiver.

2.3.4 Cable and Wiring

All wires should be in accordance with MIL-W-22759 unless otherwise specified. All cables should be in accordance with MIL-C-27500 unless otherwise specified. Use solder sleeves (for shielded terminations) to make the most compact and easy to terminate interconnects. Follow the wiring diagrams in Section 2.5 as required.

To provide easy installation of the hood, allow 3 inches from the end of the wire to the shield termination. Note: Install the hood after the wiring is complete.

Installation cabling must allow the NTX Series transceiver to be easily withdrawn for disconnection and field service adjustments. Ensure an adequate service loop in the routing of the cables.

All wiring should be 22 AWG, except power and ground connections, which must be 18 AWG or larger, as indicated on the installation drawings. Ensure that the ground connection is clean and well secured. To prevent inadvertent system failure, supply power to this system from a separate breaker or fuse not connected to any other device. NAT recommends a 5 A fuse or breaker (28 Vdc Source).

Coaxial cable should be in accordance with MIL-C-17 unless otherwise specified. Do not use coax with PVC insulation. NAT recommends Teflon dielectric cable at or above VHF frequencies or where cable runs exceed 8 feet. Note that at VHF frequencies, cable losses due to long cable runs and tight bends may cut the ERP (Effective Radiated Power) to less than 50% of specification.

To prevent RF interference between similar systems, NAT recommends that VHF FM coax runs be widely separated, or be made using triaxial cable. Bond the outer shield to the airframe at the transceiver end only.

In communication intensive applications, bad cable routing and shielding may drastically compromise over-all system performance. Symptoms will be spurious squelch opening, RFI (Radio-Frequency Interference), and garbled reception.

Neatly terminate RF cables (solder or crimp) and test for shorts prior to system checkout (not while connected to the radio!!). Keep cable bends to a minimum at the antenna.

Page 2-2 Oct 25, 2002