transistor radios have been in production for over 50 years now. even early ones are common finds at yard sales and fleamarkets. they were the ipod of the 60's and 70's and many have become sought after collectibles.
in the mid 50's an american company named regency produced the world's first commercially made transistor radio. right on their heels where several other american companies and so the battle for the transistor radio market began.
transistor radio manufacturers came and went. by the late 50's, the japanese began to produce transistor radios at prices that american industry couldn't compete with. some american companies quickly moved production to japan, others just had their radios made for them. one company stuck it out till the bitter end, it's name was zenith.
zenith radios were generally better built than any of the competitors and priced accordingly. some models like the transoceanics cost as much new as a decent used car would have cost at the time. because of their quality, many still survive. this instructable will deal only with large zenith metal chassis transistor radios. much of the info provided though does carry over to other brands of metal chassis transistor radios.