HP E4418A, Service Manual

Page: 50 / 108

Performance Tests
Power Reference Level Test
2-10 HP EPM-441A/442A Service Guide
Power Reference Level Test
Description
The power reference oscillator output is factory adjusted to 1 mW
±
0.7%.
This accuracy is achieved using a measurement system accurate to 0.5%
(traceable to the National Institute of Standards and Technology) and
allows for a transfer error of
±
0.2% when making the adjustment.
If an equivalent measurement system is employed for verification, the
power reference oscillator output can be verified to 1 mW
±
1.9%. The 1.9%
maximum error is made up of
±
0.7% factory adjustment accuracy,
±
0.5%
worst case oscillator drift for one year,
±
0.5% verification system error and
±
0.2% transfer error.
If the Power Reference Oscillator Level Adjustment is carried out before
this verification test is performed, the result obtained here will be more
accurate.
The power reference oscillator can be set to
±
0.7% using the same
equipment and following the adjustment procedure. To ensure maximum
accuracy in verifying the power reference oscillator output, the following
procedure provides step by step instructions for using specified
Hewlett-Packard test instruments of known capability. If equivalent test
instruments are used, signal acquisition criteria may vary and reference
should be made to the manufacturer’s guidelines for operating the
instruments.
Electrical
Characteristics
Performance
Limits
Conditions
Power Reference 1 mW Internal 50 MHz oscillator
factory set to ±0.7% traceable to
National Institute of Standards
and Technology (NIST).
Power Reference
Accuracy
±
1.9% Worst case (power meter
accuracy plus verification
system error).
±
0.9% RSS for one year.
4402serv.book Page 10 Monday, March 11, 2002 11:34 AM