Ametek 7124 Instruction Manual page 159

n Mode
0 Single Reference / Virtual Reference mode
1 Dual Harmonic mode
2 Dual Reference mode
NOTE: When in either of the dual reference modes the command set changes to
accommodate the additional controls. These changes are detailed in section 6.7.14
IE [n] Reference channel source control (Internal/External)
In Single Reference and Dual Harmonic mode, the value of n sets the reference input
mode according to the following table:
0 INT (internal)
1 EXT (external rear panel TTLREF IN input on Main Console)
2 EXT (external front panel analog REF input on Main Console)
3 EXT (external rear panel TTLREF IN input on 7124 RCU)
4 EXT (external front panel analog REF input on 7124 RCU)
This command is invalid in Dual Reference mode
IE1 [n] Reference channel 1 source control, Dual Reference
In Dual Reference mode, the value of n sets the reference channel 1 source according
to the following table:
0 INT (internal)
1 EXT (external rear panel TTLREF IN input on Main Console)
2 EXT (external front panel analog REF input on Main Console)
3 EXT (external rear panel TTLREF IN input on 7124 RCU)
4 EXT (external front panel analog REF input on 7124 RCU)
This command is only valid in Dual Reference mode
IE2 [n] Reference channel 2 source control, Dual Reference
In Dual Reference mode, the value of n sets the reference channel 1 source according
to the following table:
0 INT (internal)
1 EXT (external rear panel TTLREF IN input on Main Console)
2 EXT (external front panel analog REF input on Main Console)
3 EXT (external rear panel TTLREF IN input on 7124 RCU)
4 EXT (external front panel analog REF input on 7124 RCU)
This command is only valid in Dual Reference mode
REFN [n] Reference harmonic mode control
The value of n sets the reference channel to one of the NF modes, or restores it to the
default 1F mode. The value of n is in the range 1 to 127.
REFP[.] [n] Reference phase control
In fixed point mode n sets the phase in millidegrees in the range ±360000.
In floating point mode n sets the phase in degrees.
AQN Auto-Phase (auto quadrature null)
The instrument adjusts the reference phase to maximize the X channel output and
minimize the Y channel output signals.
Chapter 6, COMPUTER OPERATION
6-13