A.1,1 B.1,0 C.0,1 D.0,0
A.25D失電→STO獲電→25C獲電 B.STO獲電→25D失電→STO失電→25C獲電 C.25C獲電→25D失電→STO獲電 D.25C獲電→STO獲電→25D失電→STO失電
A.由繼電器啟動(dòng)受控 B.由驅(qū)動(dòng)三極管維持受控 C.由三極管起動(dòng),繼電器維持 D.由三極管和繼電器同時(shí)啟動(dòng)和維持