User`s guide

What values would a Vector Header record contain for this frequency response trace? Here is an example
record:
recordType:
13
recordSize:
18
unique_record:
-1
the_CHANNEL_record[0]:
5
the_CHANNEL_record[1]:
2
pwrOfChan[0]:
48
pwrOfChan[1]:
-48
Two fields in the record — the_CHANNEL_record[0] and the_CHANNEL_record[1] — tell you which
channels were used to measure response and excitation. In the example used here, these values indicate
that the channels are described in Channel Header record 5 and Channel Header record 2. Two other
fields — pwrOfChan[0] and pwrOfChan[1] — tell you what exponent was applied to each channel’s data.
(pwrOfChan[0] provides the exponent for the_CHANNEL_record[0] and pwrOfChan[1] provides the
exponent for the_CHANNEL_record[1].)
Note You must divide each pwrOfChan value by 48 to obtain the true value of the exponent.
Numbers in the_CHANNEL_record fields are indexes to Channel Header records in the file (0 refers to
the first one, 1 to the second, and so on). However, there is no correlation between a record’s index
number and the number of the channel described in that record. Channel Header record 0, for example,
could describe Channel 2 of your instrument. To determine which channel is described in the record, you
must read the record’s channelLabel field.
Standard Data Format (SDF)
B-32