Necessary Equipment and Conditions
To perform the amplitude, frequency, or standard resistor calibration, the following equipment is
needed:
• A time interval counter, with an accuracy of 1 ns or better.
• An AC/DC voltmeter, with 5 ½ -digit DC accuracy and true RMS AC measurements to 100
kHz.
• Standard resistors, with resistance known to 0.01% and Q accuracy known to 25 ppm. The
resistor values needed are 95.300 kΩ (R0), 5.970 kΩ (R1), 374.0 Ω (R2), and 25.10 Ω (R4).
• A fixture-to-BNC adapter.
The conditions for calibration include a warm-up time of at least 30 minutes and an ambient
temperature of 23°C ± 5°C (73°F ± 9°F).
Amplitude Calibration
This procedure calibrates the output amplitude at the different frequencies and output voltages. To
adjust the calbytes, press the CAL key until the message "cl I" appears in the display, where I is an
integer. The present value of that calbyte will appear in the right display. The ↑ and ↓ frequency keys
step through the different amplitude calbytes. New values are entered using the numeric entry keys.
1. Connect the AC/DC voltmeter across the two sides of the fixture. A small piece of wire
inserted in each side of the fixture is a convenient way to connect the DVM. Do not connect
either end to ground. Set the meter to AC volts, autoranging. Set the Model Z9216 to its
default conditions by pressing the keys, RCL 0 ENTER. Set the unit to constant voltage
mode.
2. Measure the amplitude and frequency for amplitude calbyte 0 (0.10 V and 100 Hz). If the
value is not within 2% of the nominal value, enter the new calbyte using the formula:
byteCurrentCal
Vmeas
omVn
NewCalbyte ×=
, rounded to the nearest integer
3. Verify that the amplitude is within 2% of the nominal value. See Table 2-12 below for the
acceptable limits for each amplitude.
4. Repeat steps 2 and 3 for 120 Hz, 1 kHz, 10 kHz, and 100 kHz (Calbytes 1, 2, 3 and 4) at this
amplitude (0.10 V). Note that, for each amplitude, the calbyte numbers are in order of
ascending frequency.
5. Repeat steps 2 to 4 for each amplitude in the table. At each amplitude, repeat the
measurement for each frequency, starting with 100 Hz and increasing to 100 Hz.
2
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