Partial Blocking Of Frequency Range - BRUEL & KJAER 1022 Instructions And Applications

Magnetic clutch
Frequency scanning can be stopped and started by making or breaking a
connection between terminals a and f providing the clutch control switch
AUTOMATIC SCANNING is off.
External Modulation
Set MODULATION FREQUENCY switch to Ext. Mod. Connect the ex-
ternal generator between the chassis and terminal b. Terminal f can be used
as chassis connection.
Oscillator Stop
For remote interruption of the output signal (stopping of the fixed oscil-
lator) terminal c should be connected to terminal f (ground). When reverbe-
ration measurements are made automaticaUy using the Level Recorder
2305, a switch in the Level Recorder can be used to ground terminal c. See
Applications. Room Reverberation Time.
Terminals d and e
These terminals are connected to an internal contact which is used for
interrupting the output signal when the instrument is being swept through
the dead zone 20kHz to 20Hz.
Note
When delivered from the factory, the Oscillator is supplied with a 6-poled
plug containing the necessary connections for dead zone blocking.
1-1. PARTIAL BLOCKING OF FREQUENCY RANGE
The initial and/or the fincH part of the frequency range can be blocked by
means of the cams mounted on the spindle of the capacitor (Fig. 4.5.). With
full use of the cams the frequency range can be reduced to approximately
one octave in any part of the frequency range.
The blocking range is adjusted as follows:
1. Disconnect the instrument from the power supply line.
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