Homer Autotuner Starting Parameters

For autonomous use of the Homer Autotuner, you do not need an external PC. In this case the automatic impedance matching is controlled by

  • Autotuner Starting Parameters, contained in the Tun.cfg configuration file, and

  • AUTOTUNE switch setting (if such a switch is provided).

The Autotuner starting parameters can be modified by treating the Tun.cfg file similarly to the Homer Analyzer Starting Parameters. An example Tun.cfg configuration file is listed below. Lines starting with a semicolon are ignored. To create your own cfg file, you can copy the code block below and use it as a template. The parameter MaxInsert_mm is related to Homer hardware.

 
[Tuner Configuration]
 
IsOn=FALSE
Targ_mU=0
Toler_mU=25
Pause_10ms=0
Smooth=1
WaitRF=TRUE
Delay5b=0
DelayStep_ms=250
HystDg=5
MaxMag_mU=1000
PowOnAction=2
AtSwitchAction=0
MotErrAction=0
MaxAttempts=10
GuardSeconds=60
 
;==========================   NOTES   =================================
;This file is not obligatory: Defaults below are used in case of absent
;lines or invalid data (some defaults are HW-specific).
 
; IsOn=FALSE        Activate autotuning
; Targ_mU=0         Target [milliunits] for autotuning
; Toler_mU=25       Tolerance [milliunits] for autotuning
; Pause_10ms=0      Minimal interval n x 10ms between tuning steps
; Smooth=1          Number of averaged measurements taken for one tuning step
; WaitRF=TRUE       Suspend tuning when RF power is absent or too low
; Delay5b=0         Tuning delay after power onset in steps DelayStep_ms
; DelayStep_ms=250  Step of power onset tuning delay
; HystDg=5          Hysteresis in degrees for stubs 1-3 swapping
; MaxInsert_mm=22.7 Limits maximal stubs insertion depth
;                   This default is HW-specific
; MaxMag_mU=1000    Max load magnitude [milliunits] for autotuning
; PowOnAction=2     Stubs on PowerUp: 0=Stay in Positions 1=AllHome
;                   2=AllHome+Move to Positions
; AtSwitchAction=0  Command to execute on changing Autotune switch state:
;                   0=Autotune on/off else Command Code
;                   Allowed codes: 2=Single Tune, 69=All Home
; MotErrAction=0    Action on hitting a terminal switch: 0=Nothing 1=AllHome
; MaxAttempts=10    How many unsuccessful AllHome attempts are allowed (1 to 1000)
; GuardSeconds=60   Minimal wait between consecutive AllHome attempts (0 to 3600)

The IsOn item activates or deactivates the autotuning at the system power-up irrespective of the AUTOTUNE switch setting. When set to TRUE, the autotuning will be active.

The AUTOTUNE switch takes priority whenever its position is changed. This also applies when using an external controller. Because status feedback is not sent to an external PC, a discrepancy may occur until the next Autotune ON/OFF command is issued from the PC. To do so, click the Tuner|Autotune|Active menu item or the  AT  button in the Tuner View window.

The meaning of Targ_mU, Toler_mU, Skip, Smooth, WaitRF, Delay5b, DelayStep_ms is explained in the Autotune section of the System Info Window topic. The meaning of HystDg is explained in the Hysteresis section. the meaning of PowOnAction is explained in the Autonomous Operation section.

By MaxInsert_mm you can limit the maximum stub extension to a value lower than the factory default.

By MaxMag_mU you can truncate the matchable area to avoid regions with a risk of arcing.

AtSwitchAction defines the action triggered by toggling the Autotune HW switch. The default (when the line is missing) is switching autotuning on and off. Depending on the AtSwitchAction value, the switch can also be used to perform a single autotuning step, or to activate the All Stubs Home procedure. All these actions can also be triggered via the Remote connector.

MotErrAction defines what action should be taken if any of the motors hits its terminal switch. If MotErrAction = 1, an attempt will be made to invoke the All Stubs Home procedure. This can resolve the problem of randomly lost motor steps in an otherwise correctly working tuner. However, to prevent incessant attempts when the tuner is indeed damaged (e.g., mechanically stuck stubs), only MaxAttempts number of attempts will be made: not all of them at the same time but mutually separated by GuardSeconds seconds.

After editing, the Tun.cfg file must be sent to the Homer (see Transferring Files) and the unit must be restarted.

For the communication interface settings, see Configuring Communication.