ATTENUATOR Controller

Operation manual

There are two wheels, each contains set of 10 attenuation foils. The wheels are located one-by-one so total thickness of foils is for x-rays a sum of foil from wheel#1 and wheel#0.
On wheel#1 there are 10 wholes (of diameter 10 mm) covered with quite thick plates of metal (Al: from 0 to 3 mm; Pb: from 2 to mm).
On wheel#0 there are 10 wholes (of diameter 10 mm) covered with thin plates of metal (Al: from 0 to 0.45mm).
Since both wheels turn independently you can set 100 different pairs thus fine tune intensity of measured beam.
 
Position
Wheel#1
Wheel#0
metal
thickness
[mm]
metal
thickness
[mm]
0 Al 0 Al 0
1 Al 0.50 Al 0.05
2 Al 1.00 Al 0.10
3 Al 1.50 Al 0.15
4 Al 2.00 Al 0.20
5 Al 2.50 Al 0.25
6 Al 3.00 Al 0.30
7 Pb 2.00 Al 0.35
8 Pb 3.00 Al 0.40
9 none user's defined Al 0.45
Thickness of attenuating foils on 2 independent wheels 
 
 

The device operates in two modes:

Operating locally
At the beginning of operation you should assure that what the Controller displays (positions of wheels) is what the hardware is set up. Especially after power-up of Controller it has no idea what is current position of the wheels and will display zeros for both. In this case you should perform device reset. After that you can operate safely.

Keyboard layout is like in telephone:

 
one less RESET one more

1

2

3

 not connected

4

5

6
wheel#1 (more significant)

7

8

9

 wheel#0 (less significant)

*

0

#

 not connected
 
 How to:
 
add attenuation heavily? Use wheel#1: press [6] once or more for increase thickness of foil rapidly
add a bit of attenuation? Use wheel#0: press [9] for increase thickness of foil by 0.05mm of Al
decrease attenuation? Use keys [4] or [7] to move wheels (#1 or #0) one position left
reset device? keeping reset button [5] pressed, press: 
  • [6] for reset wheel#1
  • [9] for reset wheel#0
  • [6] and [9] for reset both wheels
then wait few seconds until controller finds zero position(s). 
Keys [5] and [8] have same meaning (are connected inside Controller). 
Note: this step will remove all shielding from detector
undo resetting? keeping reset button [5] pressed, press: 
  • [4] for undo reset of wheel#1
  • [7] for undo reset of wheel#0
  • [4] and [7] for undo both
then wait few seconds until wheels come back to old positions. 
Keys [5] and [8] have same meaning (are connected inside Controller). 
Note: You can't undo after reset is completed
Note: When in position #9, increasing will cause jump 9->0 (remove all the foils). Similarly: decreasing from position 0 will cause jump to foil#9.
 
 

Operating remotely

Attenuator Controller has serial port which can be used for remote controlling. Settings of the port are fixed: You can use any terminal (minicom under Linux; telix, NC-term under DOS; hyperterminal under Windows) to make connection or call Attenuator's commands within your measurement scripts. A.Controller will not create any echo itself, so for your convenience set 'echo' property in terminal settings (if available).

Operating remotely you always use absolute values of wheels' positions. You send and receive ASCII strings. Lower-case ASCII will be converted to upper-case automatically. Command processing is performed char-by-char in real time. It means that a command is executed WHILE TYPING. You have to send EOL (<enter> = <CR> = <13>) sign after each command. Whitespaces and ASCII below <32> are ignored.

While connected you can use following commands: