I just bought a Pla-Pal Tombstone and I can't find anything on the internet about it. Would be interested in having some background on it, manufacturer, year built, etc. Thanks in advance.

I just bought a Pla-Pal Tombstone and I can't find anything on the internet about it. Would be interested in having some background on it, manufacturer, year built, etc. Thanks in advance. More information on this radio states that it is licensed under patent of Radio Corporation of America, General Electric Company, Westinhouse Electric, and Hazeltine Corporation. It is a battery operated radio and the patent number would indicate it was manufactured around 1930. Thanks