Click here to download script (a text file).
This script applies dechirps from 88% to 112% to the entire data file, in 1% increments. You can also right-click on this link and download and save a short test file for practice (30 sec. data file, 234 K)
To use this script, the .wav file must be open as well as the spectrum window (alt-z), before you run the macro. Then, open the Scripts and Batch Processing dialog box and check the boxes marked Pause at Dialogs and Alert When Complete.
When the script is Run, the script selects the whole file. It pauses at each gliding-stretch dialog box and waits for the user to click OK. It also pauses at the Constant dialog box, which is just a trick to insert a pause in the script. At the constant stretch pause the user hits the Scan button in the Analysis window instead. After viewing the dechirp results, hit Close in the Constant Stretch dialog box and OK in the gliding-stretch dialog box and the script continues.
This is the best way we have found to get CoolEdit 2000 to scan a long FFT (where "long" means the entire data file). If the Pause at Dialogs box is not checked, CoolEdit 2000 breezes through the script and updates the analysis window at each dechirp with just the FFT at the cursor, and not the whole selection. Having to hit Scan, Close and OK with every dechirp gives the user a chance to look at the result before the script starts the next dechirp. Without the pauses, you could easily miss a result.
The test file signal starts at 1201 Hz and drifts up to 1249.1 Hz. The sample script shows the sharpest peak and best S/N at a correction of approximately 105%. Try it yourself, and edit the script 0.1% steps or smaller to see exactly where the best peak is located.
Return to the ASRG SETI Page.