Northern Airborne Technology NPX138 - Manual (Page 47)

SM41 Rev. 4.00 NPX138 Panel Mount Radio Manual
3.9.2
Tone Display and Selection
The NPX radio displays the tones for the selected channel on the last three positions
(far right hand side) of the RX and TX lines. Use the Channel Edit mode to select and
store the appropriate tones for each channel. The operator can set different tones for
receive and transmit. Select ‘-’ if you do not require a tone.
By editing the TONE DISP status line, the operator can configure the radio to display
the tones using one of four different methods. The four tone display modes are:
• Tone Frequency (FREQ):
This is the actual frequency of the tone, measured in Hertz (cycles/second). There
are only three digits available on the radio to display this data, so the radio truncates
any decimal fraction on the display (i.e. 103.5 Hz becomes 103). Although not
displayed, the radio uses the exact frequency.
• EIA Codes (1-38):
This is a number from 1-38 that identifies the tone in sequential order from lowest
(67.0 Hz) to highest (250.3 Hz)
• Wulfsberg Codes (WCODES):
These are sequential shifted OCTAL codes based on the thumbwheel design of the
Wulfsberg C-1000 control. Because they are missing numbers ending in 0 & 9, they
can be confusing, especially to those familiar with the straight sequential number of
the EIA codes.
• Motorola Codes (MCODES):
These are alphanumeric codes that often appear in the land mobile business,
especially if Motorola equipment is used.
Nov 10, 2003 Page 3-13
ENG-FORM: 806-0105.DOT
CONFIDENTIAL AND PROPRIETARY TO NORTHERN AIRBORNE TECHNOLOGY LTD.