A.G.811基準(zhǔn)時(shí)鐘 B.G.812二級(jí)時(shí)鐘 C.G.812三級(jí)時(shí)鐘 D.G.813同步設(shè)備時(shí)鐘
A.±20x10-6 B.±4.6x10-6 C.±1x10-7 D.±5x10-9
A.756 B.378 C.1024 D.128