Testing an AM radio is easy. I have a used speaker and antennae tacked up in my shop. With a 1 amp trickle charger hooked to the radio I use jumper wires to fire it up. Works good. I also have a second speaker ready to check FM radios. Your 4-channels will be similiar.....Russ __________________________________ Do you Yahoo!? Yahoo! Mail - Find what you need with new enhanced search. http://info.mail.yahoo.com/mail_250