Port Extension; Offset Compensation - HP 41951A Operation Note

OPERATION
Calibration Plane
Figure 3-2. 41951A's Calibration Plane
The reference values of the furnished calibration standards are listed in Table 3-1.
Table 3-1. Reference Values for Calibration Standards
Reference Value
0S+jxw x 82 fF
00-іхоихон
50 0+ xwxOH
Standard
05 admittance
00 impedance
50 Q impedance
These values are stored in the 4195A's battery back-up memory as the calibration reference
values.
NOTE
Н you extend the calibration plane beyond the connecting surface of the APC-7
connector, and you have accurate standards that can be connected to the end
of the extension, calibration will be accurate to the end of the extension. Refer
to the 4195A's Operation Manual for the procedure for entering the reference
values of your standards.
3-5-2. PORT EXTENSION
The port extension compensates for the phase shift in the extension cable. This capability is
effective when the measurement terminal is extended by the 50 © low loss cable as the air
line, or when the offset compensation cannot be performed. For procedure of the port
extension capability, refer to the 4195A's Operation Manual.
3-5-3. OFFSET COMPENSATION
The 4195A applies three offset compensation; 05 & 90 offset, 05 offset, and 00 offset com-
pensation. The 05 & 00 offset compensates for the residual impedance and stray admit-
tance existing in the test fixture, that is attached on an Impedance Test Adapter. The 0S
3-3