The National GUITAR Museum - The Origins of Ovation. 48 years ago, Charles Kaman and his group of helicopter engineers submitted their plans for a roundback guitar to the US Patent Office.
Amazon.com: Guitar Construction Patent Art Old Look Print in a Beveled Black Wood Frame (5" x 7") M13419: Posters & Prints
Kaman GTX 33 Electric Guitar with Floyd Rose bridge and locking nut Purple / Green | Reverb
18 Review: I had money difficulties and had to sell it. | GTX | Electric Guitars | Reviews @ Ultimate-Guitar.Com @ Ultimate-Guitar.Com
Applause GTX Catalog
Kaman Applause GTX23 Red MIK 80's Metal Hair Band Guitar S/S/H | Reverb
Vintage 80's Kaman Applause GTX 22 Solid Body Electric Guitar | Reverb Deutschland