BRUEL & KJAER 1621 - Bandwidth Control; Overload Adjustment; Noise

Adjustment Procedure 1621.2
Bandwidth Controi
FILTER: "Linear"
FREOUENCY RANG E "20·200
MAX. VOLTAGE: "1 V"
SWEEP CONTROl "Manual"
FILTER to "23%"
FILTER to "3%"
Overload Adjustment
FILTER: "3%"
FREOUENCY RANG
E: "200-2k"
FREOUENCY TUNING: "2"
MAX. VOLTAGE: "1 V"
SWEEP CONTROL: "Manual"
Input signal: 63.2 Hz adjusted for 1 V on "Filter Output""
Frequ
Check
that the output signal is damped mora than 15 dB with FREOUENCY TUNING at the po-
sitions
35.5 Hz and 112 Hz
Check that the output signal is damped mora than 30 dB WIth FREOUENCY TUNING at the
above mentioned Irequencies
Adjust P7 for OV ± 100mV DC at the output of V6
Input signal: 200 Hz, 6 V peak
Adjust
P2 to the position where the "Overioad" lamp just starts flashing.
Check
that "Overioad" start flashing at the voltages mentioned in the scheme.
Input
Frequency
200Hz 20kHz
20Hz
I I
MAX.
VOLTAGE:
-
3%
Output voltage:
5,5 V - 6,5 V peak
"1 V"
23%
MAX.
3°' 10
VOLTAGE:~
Output voltage: 1.1 V
-
1,3 V peak
"0,2V" 23%
Noise
Short circuit
"Filter Input" to ground.
Check the noise on
"Filter Output" according to the seheme below.
Notiee! The noise should only be measured in the range from DC up to 20 kHz.
FREOUENCY TUNING
FREOUENCY RANGE
I
"0,2 2" I "2 -
2
20"
I "200
2k" "2k- 20k"
MAX. VOLTAGE
"1 V"
MAX. VOLTAGE
"0,2V"
i3%
r---
23%
3%
r---
23%
Noise below
10 mV
Noise below 2 mV
Noise
17mV
I Noise 3,4 mV
Distortion
FILTER: "Linear"
FREOUENCY RANGE: "2k-20k"
Input signal 10 kHz. 3 V RMS.
FREOUENCY TUNING:
"20"
MAX. VOLTAGE: "1 V"
SWEEP CONTROL: "Manual"
FILTER to "3%"
Check
the distortion at 20 kHz to be below 40 dB at the 1621 output.
2-2
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9.77