No, WIK, you cannot key an amp from a 706 like this. You HAFTA use an external relay on most amps. And, when you post a .pdf link like this, most of us cannot "save" it on our machines. You need to post the webpage, and then right click and select "save target as"
The web page is http://www.k6xx.com/ikanrite.html
Click on IC-706 Amplifier Switching-
control an external amp
You can either select the "HTML" page, or if you want to save the .pdf file, RIGHT CLICK on the pdf link and select "save target as"