Kessler AT-AUTO Operating Manual page 98

Reading Peak Power
The LAMP button controls both the SWR meter illumination as well as power to the
PEAK and PEAK/HOLD circuitry. It must be On in order to read peak power. De-
pressing the front panel PEAK button will activate the active peak power circuitry and the
meter will display PEP and exhibit fast attack and approximately 1.5 second delay time.
The displayed PEP will be approximately 95-100% of the SSB signal PEP, but may vary
depending upon the tonal and inflection characteristics of the user's voice (displayed power
may be greater). If the PEAK/HOLD button is depressed, the maximum PEP measured
will be "held" on the meter display for approximately two seconds. This feature is provided
to make it easier to observe the actual peak output power.
For CW signals, the peak power is synonymous with average power. Therefore, a trans-
mitter's single tone (CW) signal should yield the same displayed power level regardless of
whether the meter is set to display the average or peak power (switch selection set to AVG
or PEAK, respectively).
Note: The PEAK/AVG switch must be depressed in order for the PEAK/HOLD
feature to function properly.
Calibration
The meter was calibrated at the Kessler Engineering factory. However, it may be calibrated
with the following procedure:
1. Connect the AT-AUTO
accuracy.
2. Terminate the output of the calibrated Wattmeter into a 50 Ω dummy load.
3. Set the AT-AUTO
4. Deselect the PEAK/HOLD feature.
5. Turn On the meter LAMP (to supply DC power to the meter circuitry).
6. Calibrate the low-range AVG forward power display
(a) Set the AT-AUTO
(b) Set the AT-AUTO
coaxial output to another calibrated Wattmeter of known
(tm)
to Bypass mode.
(tm)
Wattmeter to the 300 W power range.
(tm)
Wattmeter to read AVG power.
(tm)
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