The NAV-401L test set is designed to meet the functional testing and calibration requirements of CAT II ILS systems. IT includes a modulated signal generator for MKR, VOR, LOC, G/s and COMM test and a variable output attenuator. Maximum output on any band is -7 dBm (0.1v). Output range is from -7 dBm to -110 dBm. One crystal frequency is supplied in each band and variable frequency modes allow all frequencies of all bands to be used. All bands are frequency phase-locked at 25 kHz intervals except G/s. G/s is a phase-locked at 50 kHz intervals, A separate internal localizer transmitter with an output of approximately -18 dBm at the generator output jack is provided for simultaneous radiation of LOC and G/s signals in G/S XTL mode with LOC switch on. The set includes a counter to measure the RF frequency of the signal generator in any band, the frequency of any COMM transmitter, any 0dBm external frequency from 1 MHz to at least 300 MHz, or the selected VOR bearing as a check on the cVOR BRHG. Counter time base is derived from a 210 MHz clock oscillator with an accuracy of +/- 0.002% from 0 to 50 degrees Celsius. A power meter is included to measure COMM transmitter power 0-10 W or 0-100 W/ A peak or average power switch allows COMM XMTR modulation checks and a rear panel jack permits viewing or listening to the modulation. A percentage of modulation monitor accurately indicates modulation levels on any band 0–30% or 0-100%. The NAV 401L tones for modulation are digitally derived from a 2.16 MHz crystal oscillator. The 90Hz and 150 Hz tones utilized for LOC and G/S modulation are phase-locked with an accuracy of 0.1 degrees. By pressing a front panel switch the relative phases between the 90 and 150 Hz tones can be varied in 5 degrees selected step on the OVR BRG selector. LOC and G/s centering may be calibrated from the front panel. The battery charging system will permit continuous charging without damage to the battery. The AC supply permits operation on 115 V / 230 V, 50 Hz to 500 Hz.
Aeroflex
