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until the message "df‖ appears on the left alphanumeric display and the current
value on the right display. Enter the new value, in ppm using the entry keys. To
exit the standard cal menu, press
CAL
until the "quit CAL" message appears, and
then press
ENTER
.
Standard Resistor Calibration
This procedure determines the value of the internal standards for the different fre-
quencies and ranges. The 9216A does this by measuring a precisely known resistor and
recomputing the values it uses when calculating the impedance of a part. These values
are the primary accuracy standard of the instrument, so the exact value of the calibration
resistor, both real and imaginary parts, must be known. In addition, the 9216A and the
calibration resistors must be placed in a temperature controlled room and allowed to sta-
bilize at least 30 minutes before attempting calibrate.
The standard cal menu is entered as follows: Press the
CAL
key until "Std cAL" ap-
pears on the alphanumeric display. Press
ENTER
once to get into this menu structure.
Next press
CAL
until the "rAngE‖ message appears on the left display. From here the
desired range can be entered (using the
0
to
3
numeric keys and
ENTER
) and will ap-
pear on the right display.
After the range has been entered, pressing
CAL
will cycle through a series of menus.
Pressing
ENTER
in any of these will either load that value or begin the action listed. Two
different parameters must be set, "r Std" (standard resistor resistance value) and "q Std"
(Q of the standard resistor). Resistance values are entered using the
,
k
, and
M
keys and Q is entered in ppm. Negative Q's denote capacitive resistors and positive Q's
denote inductive ones. The different actions are "StArt cAI" (start cal), "Fctry cAL" (facto-
ry cal) and "quit cAL" (quit cal). These activities will, in order, begin calibration of the
current range, recall the factory default values, or exit the cal menu.
1. Inspect the fixture contacts for dirt or waxy build up. If the fixture appears dirty,
clean it. Remove any adapters or components from the fixture.
2. Perform open and short circuit calibration.
3. Plug the R0 calibration resistor into the fixture. Enter the cal menu as described
above and enter range 0.
Press
CAL
until "r Std" (resistance standard) is displayed. Enter the re-
sistance of R0.
Press
CAL
to display "q Std: (Q standard) and enter the Q of the standard in
ppm.
Press
CAL
to display "StArt cAL" (start cal). Begin the calibration by pressing
ENTER
, making sure to keep hands and any other objects away from the fix-
ture.
4. Repeat step 3 for the other three ranges (1, 2 and 3). When finished, exit the cal
menu by pressing
CAL
until "quit cAL" is displayed and then press
ENTER
.
5. After calibration, verify that the calibration is accurate. Perform open and short
circuit calibration. Insert the standards in the fixture and measure them at 1 kHz,
series equivalent circuit. The R and Q readings should agree to within one least
significant digit of the standard values.