DavidKotelchuck.net
RP 36a Request for Phone Tap and Microphone Surveillance

Text on page 36:

Then, to “exhaust every possibility,” as Hoover had directed, the FBI sought to go beyond a simple wiretap on our home phone by requesting to plant microphones in our apartment so that the FBI could listen in on our daily lives at will. The Baltimore office’s request to Hoover to conduct a “tesur” (technical surveillance) of our home provides an interesting window on the FBI’s modus operandi:

Copy of original request: