Tektronix TDS7000 Series Programmer's Manual page 11

Headers
You can control whether the instrument returns headers as part of the query response. Use the HEADer
command to control this feature. If header is on, the query response returns command headers, then
formats itself as a valid set command. When header is off, the response includes only the values. This
may make it easier to parse and extract the information from the response. The table below shows the
difference in responses.
Comparison of Header Off and Header On Responses
Query Header Off
TIME? "14:30:00"
ACQuire:NUMAVg? 100
Header On
:TIME "14:30:00"
:ACQUIRE:NUMAVG 100
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