Blackstone Radio Tube Manufacturing Company in Pawtucket Rhode Island. There are two listings for this company that I have found, 1933 1 and 1934 2, both at 64 Broadway in Pawtucket. The name associated with the company is Abraham S Friedman. Friedman was born in New York to Russian immigrants, Maurice and Ida, in 1906 3. In 1934 7 & 1935 8 Friedman's occupation is listed as Radio Tube Manufacturer. 7
In 1927 4 and 1928 5 Friedman's occupation is listed as Commercial Collection Agency.
1933 brought some legal issues to the company, on September 27 of that year, RCA brought suit against A. S. Friedman over patent infrigments9 of the following patents in Rhode Island District Court, Doc. 455:
US1537708 W. Schottky, Thermionic vacuum tube
US1736815 W. J. Albersheim, Audion tube
US1244217 L. Langmuir Electron discharge apparatus and method of operating same
US1558437 L. Langmuir Electrical discharge apparatus
US1374679 J. B. Pratt, Degasifying process
US1855885 A. W. Hull, Electron discharge device
US1748026 L. E. Mitchell, Electron discharge device
They also brought suit in Rhode Island District Court, Doc. 456 over these additional patents:
US1432867 M. J. Kelly, Electron discharge device and method of making same
US1456528 H. D. Arnold, Electric discharge device
US1479778 H. J. Vander Bijl, Vacuum tube device
US1811095 H. J. Round, Thermionic amplifier and detector
US1850981 H. P. Donle, Rectifier
US1672233 W. J. Skinner, Radio grid and filament spacer
US1459412 A. M. Nicolson, Thermionic Tanslating device
In 1935 Abraham was married to Dorothy M Ferrara a Model from New York with Abraham's occupation listed as a Engineer 6.
In 1936 Blackstone was sued by F. M. Howell & Company, box makers. This may have been for Tube Boxes or labels and was settled in 1935, no costs.
Providence Journal April 12, 1935
Providence Journal April 29, 1936
I have seen only one example which I own.
1 1933 Pawtucket Central Falls Directory
2 1934 Pawtucket Central Falls Directory
3 1930 Census
4 1927 Directory
5 1928 Directory
6 Marriage Certificate 1935
7 1934 Directory
8 1935 Directory
9 ELECTRONICS - January, 1934