It looks like your basic format is right. You may want to include a plus sign and/or area code for your phone to trigger it.
However, the success and implementation depends on what you're trying to do and on what device/platform.
First, you'll need to actually call the function you're defining. So you'll use call(); after defining your function the way you did above. I do recommend renaming it though to something like callTele so it doesn't get confused with the built in method "call" accidentally.
That would auto start the call whenever the browser code flow got to that call.
Or do it on a click event for example. Just having the function or html anchor tag there won't do anything.
Use something like this to activate it on click : sym.getComposition().getStage().callTele();
You'll probably want to put the original function in CompositionReady on the Stage code (document ready).
Then associate the telephone function with an event within Animate, you may need to do something like create a click event on the symbol.
Lastly, you device needs to support the html5 feature. If it doesn't it won't work. try surfing some sites to see if your test device supports it. Many older desktop browsers don't either.
Thanks Mario that was very useful.
I wound up using this solution:
// insert code to be run when a user touches the object (for touch devices only)
window.open( 'tel:1-941-380-1444', '_top' );
It seems to work across multiple platforms for current states of software.