How to Use the ColtCal Program to Calibrate the Colt Audiometer
    2/26/2013 -med

The ColtCal program must be located in the same directory as the 
RETSPL files that it uses. There are six files that are used.

  ColtCal.exe
  TDH39.RETSPL
  ER3A.RETSPL
  B71.RETSPL
  SPEAKER.RETSPL
  LINE.RETSPL

There is also an alternate TDH50 file available.
  TDH50.RETSPL

In addition, the ColtCal program requires the Fryers32.DLL or FryeCom.DLL 
FIPP device driver file to be available. Either located in the same directory
as the ColtCal program, or in the Windows System32 directory.

Starting the program:

Connect the computer to the USB port on the Colt base unit and turn on the
base unit. Note the tablet is not required for calibration and should be
turned off (to prevent interference). Also note that you will need to know which 
com port the USB driver is attached to. 

Start the ColtCal program.
Select the Com Port from the drop down list at the top left corner of the window.
Click on the Connect button to connect to the Colt. 
The device information will be updated and the background will become light green 
if the connection is successful.
If the port could not be opened or the Colt could not be found, the connection
panel will be pink. 
The status bar at the bottom of the window will show the status of the program activity.

You can click on the Exit button at any time to exit the program. 

Normally you should leave the Auto Set HL checkbox checked. 
this will automatically adjust the HL setting to the preferred HL level for calibration.
If you wish to use your own HL level setting, uncheck the box and set the dB HL dropdown
selector (below the "Save All" button) to the desired HL setting. 

If you hover the mouse over a control, a "hint" message will be displayed telling you 
what the control is used for. Some people find the hints annoying. You can turn them off
by unchecking the Hints checkbox. 

The Port Information provides the current port connection state information. 
This is used by technicians to determine what might be wrong if things don't work. 
Note: Double clicking on the "Port Information" label will generate a file
(CmdList.txt) that contains a list of all the FIPP commands that were performed 
since the program was started. This is provided to help the technicians.

The panels just below and to the right of the Port Information box contain 
information about the Colt instrument that the program is connected to. 
Below the panels is a smaller panel called "Aud Panel". 
This a shorthand reference window that indicates the current internal 
operating state of the Colt Audiometer. 

The Colt Calibration program requires a lot of window space to show everything needed
during calibration. You can reduce the window size by selecting a subset of the window
information using the radio buttons in the Show box. Selecting Earphones will hide the
Speaker and Line calibration section. Selecting Speakers will hide the Earphone (and Bone) 
calibration section. Selecting All will show the full calibration window.

When the program connects to the Colt, it will read out the current calibration information
from the Colt and display it in the calibration grids. 
If there was a problem reading the calibration or the calibration has a problem, 
the grid will be set to pink color. 

If the Colt has not yet been calibrated, the panel above the transducer selection 
in the grid will be yellow and it will show "Not Calibrated".
To start the calibration process, double click on the panel just above the transducer
label (eg "Left Phone"). This will bring up the calibration info edit window. 
Enter the required information into the window. If you select one of the predefined 
Device IDs from the drop down list, then Click on the Default button, the transducer
identification, date and expiration fields will be automatically filled out for you. 
Enter the device serial number (if not available you can leave it blank). 
Then enter the identification of who is performing the calibration in the Cal By Who box.
At the bottom of the window is a note showing the file that must be available to provide
the calibration information for the transducer. The file must be located in the same 
directory as the calibration program. The file name is created based on the text entered
in the "Transducer" field and adding the ".RETSPL" tag to the name. 
The file is an ASCII text formated file which contains the calibration information
for the transducer. (See the RETSPL file format description for details.)
Click on the OK button when you are done. 

You are now ready to perform the calibration for the transducer. 
Click on a number in the grid. As an example, click on the number in the Left Phone Tone 
column in the 1000Hz row. 
(Note: A valid RETSPL file for the transducer must be present for this to work.)

A small calibration window will pop up showing the selected HL level, the current 
calibration correction, and the Target in SPL that the transducer should be producing. 
If you need to, you can adjust the HL level by selecting a new value from the dB HL
drop down list.  To increase the SPL output from the transducer, click on the 
Increase button. To reduce the SPL output level, click on the Decrease. The amount of
increment or decrement can be set by the Increment dB drop down list. 
You can alternately directly enter the correction number in the Correction dB 
box then click on the target button to the right of the correction field
(or just press the return key). When the number in the correction field does not
match the value in the colt unit, the dialog box will be a yellow color. 
If there was an error, the dialog box will be a pink or red color. 
If the correction value was successfully updated, the dialog box will be green.  
To disable the output for the transducer at that frequency, enter a non-numeric 
value in the Correction dB box (example: "x"). 
Click on the Done button when the desired SPL level has been set.

The currently selected grid location will be shown as a light yellow color. 
A grid location that does not have valid calibration data it will be a pink color. 
A grid location that has been calibrated will be a light green color. 
A grid location that cannot be calibrated or has been disabled 
(such as 16000Hz for the TDH39 earphone) will have a "---" in it's position.

Click on the next grid location to calibrate the next frequency. 
Calibrate all the frequencies, including the Tone and NBN values for the transducer.

If the AutoCal NBN is checked, you only need to calibrate the 1KHz NBN value. 
The other frequencies will be automatically determined based on the difference
determined between Tone and NBN determined at the 1KHz calibrations. 

At the bottom of the grid are three additional values to be calibrated, 
S.Noise (speech noise), W.Noise (white noise) and Speech. 
Speech noise and white noise are calibrated just like the pure tone frequencies. 

The "Speech" selection requires an additional step to calibrate. 
Note: This calibration step requires that a standard 3.5mm stereo patch cable 
be connected between the Monitor output and the External input. 

The 0 VU position must be calibrated first. When you double click on the 
"Speech" grid location a small calibration window will pop up as before, but
it will show a VU meter. 

By default the AutoCal VU checkbox is checked.
This will calibrate the VU circuits automatically. To calibrate the VU
circuit manually, uncheck the AutoCal VU checkbox. 
Then Click on the Increase or Decrease buttons to adjust the
meter for 0 VU. Click on the Done button when the 0 VU is calibrated.

When you click the VU meter calibration Done button, the Speech RETSPL 
calibration window will appear. Adjust the SPL output as you did with the 
pure tone selections and click on the Done button when you have adjusted 
the SPL level to the target level. 

Note: Speech calibration is used for the External Inputs, 
Microphone (talk forward mic) and the speech File inputs. 
They all use the same calibration information.

Click on the Save to NVS button at the top of the calibration grid to save the
calibration information to the Non-Volitile Storage (EEPROM) in the Colt base unit. 
Note: you can click on the Save button at any time to save the calibrations
that you have done up to that point. This can be useful if you are interrupted.

Repeat the above for each of the transducers attached to the Colt. 


Other features:

Several additional features are provided to make calibration more useful. 

If you double click on the grid title for the transducer (eg Left Earphone),
a small window will pop up allowing to you restore the calibration from 
several different areas. Note: If you read the calibration from the Colt
NVS (EEPROM) by clicking on one of the buttons, it will replace any calibration
changes you made that have not yet been saved. 

Currently Active is the current calibration in memory of the Colt base unit. 
This can be used to refresh the transducer calibration data in the grid if 
you are uncertain if the program calibration data matches
the calibration data in the base unit. 

Stored Cal is the stored calibration in the NVS (EEPROM). Clicking this button 
will read the calibration into memory and transfer the information to the 
calibration program. Note: This will discard any calibration changes you 
made that were not yet saved.

Factory Cal is the stored factory calibration in the NVS (EEPROM) that was 
stored at the factory during factory calibraiton. Clicking this button 
will read the factory calibration into memory and transfer the information 
to the calibration program. This can be used to restore the calibration to
a known good starting point. 

Default Cal is the default calibration (fail safe) values for the Colt. 
Clicking this button will read the default calibration into memory and transfer 
the information to the calibration program. This can be used to obtain 
a starting point for calibration if the calibration has not yet been done.

If you click on the Cancel button, the existing calibration will be left unchanged.


When you click on a grid selection, the transducer will be selected and the output
presented. If you need to do somehting else for a while, leaving the sound on
can be annoying. Clicking on the Off button above the frequency column will turn 
off the sound being presented by the transducer. Just click on the desired 
calibration grid position to turn the sound back on. 


If you click on the Save All button at the top left corner of the calibration 
grid section, it is the same as clicking on all of the individual Save to NVS 
buttons for that grid section. 

At the top middle of the calibration program window is a small box with the 
title "Read All Cal" and one below that with the title "Save All Cal". 

Clicking on one of the buttons in these boxes will perform the indicated operation.
Clicking on the Read All Cal "From NVS" button will read the calibration from the NVS
(EEPROM) and update the calibration program. Clicking on the "Factory" button will
read the factory cal from the NVS and update the calibration program with the 
factory calibration values. Clicking on the "Default" button will read the default 
calibration data from the Colt base unit and update the calibration program
with the default calibration data. 

Clicking on the Save All Cal "To NVS" button is equivalent to clicking on all
of the individual "Save to NVS" buttons.

By clicking on the FIle button, you can save the current calibration data to a 
computer file. Once the Save To File dialog is displayed, just click on the 
Save button to sve the data to the file. A file will be automatically created
based on the serial number of the Colt instrument and the current date. 
Files with the same date will be overwritten. A new date will cause a 
new file to be created. The data is saved as a CSV file for inport to a 
spreadsheet or database.

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