Bird Technologies 4304A - Manual (Page 32)

21
Calibration Checks
Seup Test
Note: This test determines if the wattmeter needs recalibration:
1. The following equipment is required, connected in series with the Bird
4304A (Refer to Figure 9).
•
RF source
•
Low pass filter
•
Reference, known accurate, wattmeter
•
50
Ω load
•
Cables
Note: Keep all connections as short as possible to minimize mis-
match and insertion losses.
2. Set the RF source to produce a signal with power in the upper one-third of
the scale for each power range.
3. Compare the reading on the Bird 4304A with the reference wattmeter.
Note: If the unit is outside the stated accuracy range, return it to a
Bird Service Center for calibration.
Figure 9 Calibration Check Setup
Calibrating a Bird Element 4304A-1
Required Equipment
•
RF source capable of 100W from 25 MHz to 1000 MHz
•
RF source capable of 500 W at 405 MHz
•
Power standard
•
Model 4304A Wattmeter
5
15
50 150
500
Low Pass
Filter
4304A RF Source 50 Load Ω Reference
Wattmeter