General Dynamics 7200 - 3.0 Two-Speed Internal Alignment

TWO--SPEED RESOLVER CALIBRATION
3.0 Two-Speed Internal Alignment
The resolver system used in the standard 800225-05 option package for the 7200
ACU is an electrical two-speed resolver type. Due to finite manufacturing
tolerances, cable length differences, and other variables, the coarse and fine
resolver 0 points may not necessarily coincide.
In the case of the standard 32 to 1 ratio, this can result in 11.25 degree skips and
jumps when the antenna moves through an unaligned 0 point. To correct this,
perform the following procedure:
1. From the Main menu, select Edit system configuration..., then Position
encoder configuration.... Set Encoder type to Standard accuracy (2500 Hz)
and save changes.
This effectively ignores the fine (32:1) resolver, and provides a stable display
with which to work while performing the alignment procedure.
2. From the Main menu, select Display system status..., then select RDC states.
The fields indicated by --- data --- display the actual resolver position as being
read by the 7200 ACU. Note that the value is in hexadecimal notation.
3. By alternating between this screen and Manual antenna control, move the
antenna until the AZ and EL resolvers are on a multiple of 0800h (0800
hexadecimal); i.e.: 0000h, 0800h, 1000h, 1800h, 2000h, etc. When this is
accomplished, record the fine resolver values for AZ and EL.
4. Return to the Position encoder configuration... menu. Change Encoder type to
2-speed resolvers. Press [PRIOR] and save changes.
5. Re-enter the Position encoder configuration... menu. The 2-speed internal
alignment field will be visible. Enter the fine resolver values for AZ and EL
that were recorded in step 3 in these fields, then press [PRIOR] and save
changes.