be used to test for compression effects on tape, for example). Some users define
sequences to test different pieces of equipment, and make each sequence select a different
tolerance within the LA102. For example, sequence 1 might be set up to test a Studer
tape machine and select the Studer tape tolerance, while sequence 2 might test a Sonifex
cartridge machine and select a suitable user tolerance. The sequences may even perform
exactly the same tests, but just generate different source messages, or select different
tolerances to be applied.
Sequence definitions can be entered using the built-in LA101 sequence editor or by using
Lin4win Support Software running on a remote computer. The latter approach allows
sequence definitions to be saved to disk and edited more easily.
Computer support software Storage on disk
Most users will find that they only need a few short sequences to meet their requirements,
and these can easily be entered using the LA101 keyboard. Since sequences are held in
non-volatile memory, they should not need to be entered again, although in case of a
battery failure it is best to keep a written copy, or a copy on disc using our support
software.
4.1 The Sequence Definition
The sequence definition begins with an optional sequence title (up to 21 characters),
within quotes, and is followed by a string of test segments, each comprising a single
segment letter, optionally followed by a segment level.
For example, the default sequence 1 is:
"GENERAL/TAPE TEST" T R C I N Z
The title string is displayed on the LA101 when the sequence is run, and the test segments
will measure test level at 0dB (T), frequency response at -10dB (R), crosstalk at 0dB (C),
distortion at +8dB and -10dB (I), CCIR weighted and unweighted noise (N), and phase
(Z). The full list of segments is given in table 3.2. To add a MOL test (segment H) and a
W&F test (segment W), and to make the sweep (R) run at -4dB, this sequence could be
changed to:
"GENERAL/TAPE TEST" T R-4 C I N Z H W
Sequences should usually start with a test level segment (T or V) as some other segments
use this as a reference (noise, for example is referred to the measured test level, while the
level range used to measure frequency sweeps is calculated from the measured test level).
Segment W if present, should be at the end of the sequence as its de-selection may create
a transient signal. Otherwise the order of the test segments is not important.
Test segments are indicated by a letter, A-Z or a-z, and the case is important (Z is not the
same as z). Some care must be exercised, especially when entering these characters
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4. User Defined Sequences
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