Getting Ready
Introduction
The performance tests described in this section are designed to verify with a high degree
of confidence that the unit is performing correctly.
Serial Number
If you need to contact Stanford Research Systems, please have the serial number of your
unit available. The 5-digit serial number is printed on a label affixed to the rear panel.
The serial number is also displayed on the CH1 and CH2 displays when the unit is
powered on.
Firmware Revision
The firmware revision code is shown on the Reference display when the unit is powered
on.
Preset
Throughout this chapter it will be necessary to preset the lock-in to a known state, the
factory preset state. To do this, press Shift then Recall.
Warm–Up
The lock-in should be turned on and allowed to warm up for at least an hour before any
tests are performed. The self-test does not require any warm-up period.
Test Record
Make a copy of the SR844 Performance Test Record at the end of this chapter. Fill in the
results of the tests on this record. This record will allow you to determine whether the
tests pass or fail, and also to preserve a record of the tests.
Necessary Equipment
The following equipment is necessary to complete the performance tests. The suggested
equipment or its equivalent be used.
RF Synthesizer
Frequency Range
Frequency Accuracy
Amplitude Accuracy
Amplitude
Recommended
Power Splitter
Mini-Circuits ZFRSC-2050 or equivalent
Feed-Through Attenuators
Mini-Circuits CAT-3 or equivalent
Mini-Circuits CAT-20 or equivalent
10 kHz to 200 MHz
better than 5 ppm
1.0 dB
capable of at least +10 dBm output
Marconi 2023
Performance Tests
SR844 RF Lock-In Amplifier
5-3