BRUEL & KJAER 2006 - Automatic Recording of RF Voltages

of the amplifier. If the voltage B is smaller than the voltage A this
requirement is fulfilled.
In Fig. 4.5 is shown a set-up for measuring the oscillator voltage on the
antenna terminals.
Automatic Recording of RF Voltages.
At the rear connection plug pins 3 and 4 (4 is grounded) the DC voltage to
---,
I
I
I
I
I
I
I
I_ --,____,_______,
antenna
impedance
To rear connection
pin 3 and 4
Fig. 4.6. Relative fieldstrength as a function of time. Set-up.
ODDDOOOO OO DOOODOOO DDOODOOOOO OOODOODOOOOOODDOD OO ODOODDOO
10 15 20 ...,,.,_ min.
-J---.-.t--+-1
OP 1102
Fig. 4.7. Recording of relative fieldstrength as a function of time. Measured
indoor
with a Room antenna.
f = 97 MHz
Paper Speed: o.3
mm/sec.
Writing Speed: 250 mm/sec.
Low. Lim. Freq.: 50 Hz
Rectifier Res.: DC
Potentiometer: 25 dB
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