NGT—Checks and adjustments
146 NGT Transceiver System Technical Service Manual
Test equipment required
The following test equipment is required:
• a 50 MHz oscilloscope with an external trigger capability
• a 10× oscilloscope probe with an input impedance of 10 MΩ and less than 20 pF
• a 50 Ω RF dummy load and power meter rated at a minimum of 100 W RMS (rated
to 1 kW PEP (500 W CW) for high-power amplifier adjustments)
• an RF signal generator covering the range 400 kHz to 30 MHz, with a calibrated
output of –130 dBm to 0 dBm from a source impedance of 50 Ω
• a 50 MHz frequency counter with a resolution of 1 Hz
• a regulated power supply of 13.6 V ±0.2 V at 20 A peak
• two-tone audio generator operating at 700 Hz and 2300 Hz, with balance control
and adjustable output 0 to 100 mV RMS
• a digital multimeter with a 10 MΩ input impedance
• an AC voltmeter with a range of 10 mV to 10 V
• transceiver test unit to Codan drawing 04-03272 (the microphone isolating
transformer should be fitted with a µ-metal screen to prevent the 50 Hz mains from
being picked up)
• an RF spectrum analyser capable of measuring intermodulation
• NGT test handset for use with 2011 RF Units during tests that require a GPIO
connector