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Making an online grabber

Some people have asked what is necessary to create an on-line grabber to make available captured Spectrum Lab images for others to see. This is the technique I used. The idea was given to me by John GM4SLV last winter.

1. Get a Dropbox account from http://www.dropbox.com/

2. Install the application on your PC. This allows you to save files to a virtual server and to have some private webfiles and some that other people can view in a public directory.

3. In Spectrum Lab set up the "screen capture option" to save to a filename in your Dropbox public folder on your PC. On my PC the screen capture "periodic action" macro in Spectrum Lab is capture("C:\Documents and Settings\Rog\My Documents\My Dropbox\Public\xbm_grab.jpg"). You will have to create something similar. Press the "Test" button and, if all is working with the link, it should say "ok". Spectrum Lab will now save the image to your public dropbox folder on your PC which is also uploaded to the Dropbox site on the internet where it can be viewed by everyone once they are told the URL. Set the interval to the frequency you want the page to be refreshed. For long carrier signals 30 minutes is fine.

4. Go to the Dropbox website and log-in. Get the URL that is public for this automatically uploaded file. This is the web address everyone will have to enter to see the image you have saved.

5. Tell people the URL of your captured image.

6. That's it! You should now have your Spectrum Lab screen being uploaded to the internet at the URL given in the "copy public link" on the Dropbox page. Of course you could embed this image location into your website by linking to the image's URL.  As an example of this, see my grabber page on this site at https://sites.google.com/site/sub9khz/vlf-grabbers/xbm-grabber.

You can set Spectrum Lab to save the images at a period of your choice. In my case it updates the image every 30 minutes.