HP 3562A Operating Manual page 107

(;hapter 2-Using the Log Resolution Mode
FREQUENCY SPANS IN THE LOG RESOLUTION MODE
Real Time Bandwidth
The real time bandwidth (RTBW) is the maximum frequency span you can measure without
missing input data. At spans greater than the RTBW. the instrument's processing time exceeds
its data collection time and part of input slgnEJ is ignored while the prevIous time record IS
processed. When measuring periodic signals. the RTBW is not important because any data
lost in one record will be repeated in the next record. However, RTBW is very important when
measuring nondeterministic signals. In the log resolution mode, only one-decade measure­
ments can be made in real time. To achieve the greatest possible RTBVV, activate fast averag­
ing (in the A Va menu) and select the single display format (the SINGLE key). The message
"Real Time" is displayed althe end of the measurement if there were ne gaps in the data.
NOTE
The HP 3562A double-buffers the input signals, so 1- and
2-average measurements are always in real time.
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