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We have searched the National Archives Catalog and located 79 results for Research and Development Division and 194 Results for Ground Signal Equipment Branch in the years of 1940-1949 in the Records of the Office of the Chief Signal Officer, 1860-1985 (Record Group 111). These records are in the format of still pictures, motion pictures and textual records located at the National Archives in College Park, MD. For more information about these records, please contact the National Archives at College Park - Textual Reference (RDT2) at email@example.com, the National Archives at College Park - Still Pictures (RDSS) at firstname.lastname@example.org, or the National Archives at College Park - Motion Pictures (RDSM) at email@example.com.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from National Archives at College Park. We apologize for this inconvenience and appreciate your understanding and patience.
We hope this is helpful. Best of luck with your family research!
Thank you, Alicia, for giving me such a good place to start!