BRUEL & KJAER 2006 - Directional Characteristics of Antennas; Control of Signal Generator; Correction Curve

25 dB to be recorded. To have the fieldstrength in V/m the antenna must be
calibrated.
Directional Characteristics of Antennas.
With a set-up as shown in Fig. 4.8 the directional characteristics of antennas
can be measured. For this type of measurement polar diagram charts QP 5102
should be used on the Level Recorder. The antenna is mounted on the turn-
able Type 3921, which is synchronized with the Recorder (see the instruction
manual for the Level Recorder). Fig. 4.9 shows the directional characteristic
of a simple dipole. Here too the antenna must be calibrated if the field-
strength is desired in V /m.
Fig. 4.9. Directional characteristic of antenna.
Control of Signal Generator.
Correction Curve.
The high accuracy of the Heterodyne Voltmeter makes it possible to use it to
check the output voltage of a signal Generator as shown in Fig. 4.10.
However, it is very important that the matching impedance is correct and
the signal Generator must be loaded with its matching impedance.
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