Tabor Electronics 5251, User Manual, Page: 227 / 298

5
Performance Checks
Test Procedures
5-5
Frequency
Accuracy
Frequency accuracy checks tests the accuracy of the internal
oscillator. The internal oscillator determines the accuracy and stability
of the entire generator.
Frequency
Accuracy, Internal
Reference Equipment: Counter
Preparation:
1. Configure the counter as follows:
Termination: 50
Ω
, DC coupled
2. Connect the 5251 output to the counter input – channel A
3. Configure the 5251 as follows:
Waveform: Squarewave
Amplitude: 2
V
Output: On
Frequency:
As specified in Table 2
Test Procedure:
1. Perform frequency Accuracy tests using Table 2
Table Chapter 5-2, Frequency Accuracy
5251 Setting Error Limits Counter Reading Pass Fail
10.0000000 Hz
±
10µHz
1.00000000 kHz
±
1mHz
100.000000 kHz
±
100mHz
1.00000000 MHz
±
1Hz
100.0000000 MHz
±
100Hz
Frequency
Accuracy, External
10MHz Reference
Equipment: 10MHz reference (at least 0.1ppm), Counter
Preparation:
2. Leave counter setting and 5251 connections as in last test
3. Connect the 10MHz reference oscillator to the 5251 10 MHz
reference input
4. Configure the 5251 as follows:
10 MHz: External
Waveform: Squarewave
Amplitude: 2
V
Output: On
Frequency:
As specified in Table 3
Test Procedure:
1. Perform frequency Accuracy tests using Table 3