Don't spend money on old radios. If you find one, it'll likely have an old battery in it which will also have to be replaced. So your $30 bagain becomes a $60 radio, which then can only be used with one of your planes so you wind up with 2 or 3 $60 radios. It's so much wiser to invest in a new 2.4ghz computerized radio so you don't have to buy something else every time you add a plane and you'll get all the advantages of the last 10 years of radio development.