Ameri-King AK-451-ELT - Manual (Page 97)

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
Adjust the reference amplitude to place the peak of the carrier slightly above
the top graticule fine.

Enable the "fine" amplitude adjustment. Set the carrier peak to exactly the
top of the reference line.

Read the displayed amplitude.

Repeat for the 243.0 MHz harmonic (change the "Center Frequency" to
243.0 MHz. All other settings remain the same).

The minimum allowed amplitude on 121.5 MHz and 243.0 MHz is 20 dBm,
after 3 minutes of operation.
3.5.2.2
406.028 MHz Power Output:
Note:
The power output is approximately (35.34 – 38.18) dBm. Ensure adequate attenuation
is inserted in-line between the ELT's 406.028 MHz output and the input to the
spectrum analyzer to protect the analyzer's input circuitry.
Connect the equipment as shown below:
Set the Spectrum Analyzer as follows:

Center freq: 406.028 MHz

Span: 1 MHz

Resolution bandwidth: 1 MHz

Vertical display: 10dB/Div

Sweep: Auto

Peak/Avg: Peak

Reference level: 30 dBm

Time/Div: 20ms

Max hold: On

Attenuator (as required) on Input
Turn the ELT on and wait approximately 50 seconds for the 406.028 MHz transmitter
to turn on (transmitter sends out first signal at 50 seconds then every 50 seconds
thereafter). Determine the power output from the stored waveform.
The 406.028 MHz power output should be (35.34 – 38.18) dBm (3.42W min to
6.58W max), after 3 minutes of operation.
ELT BNC
Connector
Applicable
attenuator
Spectrum
Analyzer