Tonghui TH1953 - Calculate:scale Subsystem

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8.2.14 CALCulate:SCALe subsystem
This subsystem is mainly used to set and control the mathematical operations of the instrument.
8.2.14.1 CALCulate:SCALe:DB:REFerence
Description: Stores the relative value in the multimeter's dB relative register, which is used for the dB function in
CALCulate:SCALe:FUNCtion. When the dB function is enabled, this value is subtracted from each voltage
measurement after the measurement result is converted to dBm.
Syntax: CALCulate:SCALe:DB:REFerence {<reference>}
CALCulate:SCALe:DB:REFerence?
Parameters:
Example: CALC:SCAL:DB:REF -10.0
8.2.14.2 CALCulate:SCALe:DBM:REFerence
Description: Select the reference resistor to convert the voltage measurement to dBm. This reference affects the
dBm and dB calibration function.
Syntax: CALCulate:SCALe:DBM:REFerence {<reference>}
CALCulate: SCALe: DBM: REFerence?
Parameters:
Example: CALC: SCAL: DBM: REF 300
8.2.14.3 CALCulate:SCALe:FUNCtion
Description: Select the operation to be performed by the calibration function.
The DB performs a relative dB calculation. The result is the difference between the input signal and the stored DB
relative reference value (CALCulate:SCALe:DB:REFerence), both values are converted to dBm (dB =
measurement in dBm – relative value in dBm) . dB calibration is only available for ACV and DCV measurements.
The DBM performs a dBM calculation. The result is a logarithmic expression based on the power passed to the
reference resistor (CALCulate:SCALe:DBM:REFerence) and relative to 1 mW.
(dBm = 10 × log
10
(measurement result
2
/ reference resistance / 1 mW)). The dBm calibration is only available
for ACV and DCV measurements.
The PCT performs a percentage change operation. The result is a percentage change in the measurement results in
the reference value:
Result = ((measurement result - reference value) / reference value) * 100
SCALe performs Mx+B operations. The result is the measurement result multiplied by the gain value M
(CALCulate:SCALe:GAIN) + offset value B (CALCulate:SCALe:OFFSet). The Mx+B calibration applies to all
measurement functions except ratio, continuity and diode.
Syntax: CALCulate:SCALe:FUNCtion {DB|DBM|PCT|SCALe}