LBXXXA Series USB Powe
™
Product Manual PMA (Power Meter Application)
Revision: 08/02/11
- 37 -
Recorder
The
Recorder
output function (option 001) is a 0
– 1 VDC settable output that is proportional to the measured RF input
power.
Recorder
only works in CW mode. A window will appear to indicate the meter is in record mode if enabled.
The meter display will be inaccessible until you exit this function. Recorder Out and Trigger In share a bi-directional
connector labeled TI/RO and their operation is mutually exclusive. Setting up the recorder output is independent of
enabling or disabling the feature.
The setup for the
Recorder Out
is straightforward: You need to specifiy a power level for the Zero Volt Level; specify a
power level for the One Volt Level; and specify the units of measure. Units of measure serve to specify the power
levels and they are used to specify the scale for interpolation. That is, if the units are logarithmic (dBm, dBuV, etc.), the
interpolation between 0 VDC and 1 VDC will be with respect to that scale. Likewise, if the units are power (Watts or
Volts), the interpolation will be with respect to that scale.
For example, if you set the 0 VDC level to -30 dBm and the 1 VDC level to -20 dBm then -25 dBm would produce 0.5
VDC. And if you set the 0 VDC level to 1 mW and the 1 VDC level to 7 mW, then a reading of 4 mW would produce
0.5 VDC.
The relationship of the limits and power levels are determined by the user. The recorder output passes through a 10
Hz hardware filter and the output is updated each time the power is measured so that the rate of update is tied to your
rate of measurement. Perform the following to increase the rate of update:
1. Reduce the number of averages.
2. Increase your rate of measurement.
3. Run as few processes as possible on the PC that is being used.
4. Minimize other tasks.
