Tektronix CMC251, User Manual

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Reference
CMC251 User Manual
11
Frequencies Between 80 MHz and 1.3 GHz
1. Press the FUNC button until FREQ B is indicated by a lighted
LED.
2. After determining that the signal voltage level is 1 V rms or less,
connect the signal to the CHANNEL B INPUT connector.
3. Press the GATE button to select the desired display resolution.
Refer to Tables 4 and 5 for resolution-versus-gate settings.
Table 4: Gate Time Versus Resolution for Channel A
GATE Setting Gate Time Resolution
PRESCALE Off PRESCALE On
X1 0.01 seconds 100 Hz 1 kHz
X10 0.1 seconds 10 Hz 100 Hz
X100 1 second 1 Hz 10 Hz
X1000 10 seconds 0.1 Hz 1 Hz
Table 5: Gate Time Versus Resolution for Channel B
GATE Setting Gate Time Resolution
X1 0.016 seconds 10 kHz
X10 0.16 seconds 1 kHz
X100 1.6 seconds 100 Hz
X1000 16 seconds 10 Hz
Making Period Measurements
A Period measurement is the time in seconds for a signal to complete
one entire cycle. This measurement is taken by averaging the signal
events for a certain number of internal clock pulses. Therefore, the
gate setting determines the resolution (or accuracy) of the reading.