1307775 Control of printers BURROUGHS CORP 10 Dec 1970 [23 Dec 1969] 58621/70 Heading G4H A selective serial printer comprises a rotatable print drum 13, Fig. 1, a hammer carriage 25 movable along the print line by a belt 17 engageable with the carriage 25 through clutch means 43, and a two-ended transducer 57 having first transducing means 59 at one end responsive to a timing disc 19 and second transducing means 61 at the other end responsive to a second timing disc 21, the first transducing means generating hammer firing pulses and the second transducing means generating clutch 43 actuating pulses. The two-ended transducer 57 comprises a permanent magnet 65, Fig. 2, which may be a ceramic magnet, disposed between and in contact with two polepieces 59, 61 having coils therearound in the same sense and connected in series. A pin 63 on disc 21 induces a signal in the coil on polepiece 61 to command engagement of the clutch means 43 by solenoid 45, Fig. 2, and displace the hammer carriage, and teeth 49 on disc 19 induce signals in the coil on polepiece 59 to indicate the position of the drum and cause operation of the hammer under control of a data source 77. The printer is substantially as described in Specification 1,198,396 (see Division B6).