Fluke 5790B - Page 38

5790B
Service Manual
2-12
50 ohms
10dB
ATTENUATOR
SWITCHABLE
ATTENUATORS
0, 10, 20, OR 30 dB
Z1
Z2
CHOPPED
REFERENCE
80 Hz
UPPER FOUR RANGES ONLY
LOWER FOUR RANGES ONLY
50 ohms
LOAD
Z3
AMPLIFIER
U3
CHOPPED
REFERENCE
80 Hz
SWITCHABLE
ATTENUATORS
0, 10, 20, OR 30 dB
Z4
DC
OFFSET
FEEDBACK
AMPLIFIER
U2
DC
OFFSET
FEEDBACK
AMPLIFIER
U5
RANGE
COMPARATORS
SENSOR
DC LOOP
RMS
SENSOR
A6A2
COUNTER
CIRCUIT
TO A15 A/D ASSEMBLY
TO A15 A/D ASSEMBLY
ALL RANGES
elu012.eps
Figure 2-7. A6 Wideband Assembly Block Diagram