Applications; Automatically Recording Harmonics - BRUEL & KJAER 1022 Instructions And Applications

2. Press pushbutton marked SINGLE CHART and hold in. (Paper will
move and the reference voltage commences to record). Release push-
button when paper has moved to about the "200" c/s line.
3. Units are correctly synchronized when switching from the 80
ci s
to the 100 c/ s filter takes place on the 90 c/ s line.
4. As a means to see how far the paper has to be shifted, it is re-
commended to draw a line, by means of the "100 mV Ref." button
on the front plate of the Recorder, at the point where the paper has
stopped. By using this line as a reference the paper can be shifted
the appro· p riate distance to give correct synchronization.
5. To check the synchronization, run the recording until the pen is
stopped on for example the 2ooo c/ f> line. When correctly syn-
chronized, the switching of the 800 c/s to the 1ooo c/ s filter should
now take place at the 900 c/ s line. If this is not the case repe• a t
from item 2.
G. Finally reset the Writing Speed on 250 mm or lower if the large
figures are being used, and to a figure of 500 mm or less if using
the small figures.
To complete the synchronization sequency the B.F.O. Type 10· 2 2 must be
synchronized with the f~·equency cal·ibration on the paper.
1. Rotate main scale of B.F.O. manually until it corresponds to the
frequency denoted by the stylus, firstly moving it to a higher fre-
quency and then rotating it back until it arrives on the desired
frequency. This will take up any possible backlash with the gears
of the B.F.O.
2. Move the switch AUTOMATIC SCANNING of the B.F.O. to the "on"
position.
All units should now be in complete synchronization and on
switching the toggle switch of the PAPER DRIVE on the Recorder
to "start", the combination will operate in complete unison.
EXAMPLES OF APPLICATIONS
Applications for the combined B.F.O. 1022 and Level Recorder 2305 have
been described, and illustrated, under this heading in the earlier phase of
this manual. Now one important use for the treble combination, B.F.O.
+
Level Recorder
+
Spectrometer (i.e. the AF Response and Spectrum Re-
corder Type 3332) will be described, followed by another example using
the Spectrometer and Level Recorder with the exclusion of the B.F.O. 1022
section.
Automatically Recording Harmonics.
The Type 3332 combination is well-suited for the automatic recording of
harmonic distort• i on, as the Spectrometer can be switched to select any
specific harmonic component of the fundamental in use, up to and including
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