
System X circuit board from digital switching subsystem, 1980
1980
1980
1846
1855
1914-1918
2014
1814
1855
1760-1772
1903-1920
1920-1960
26-1-1944
1965-11-18
1794-03-03
1824-1830
26-1-1944
26-2-1944
1930-1955
1905
1934-01-14
1934
1896
1801-1900
1801-1900
1918
2017-2018
1936
1847-1923
circa 1945
1837-1851
1940
1847-1890
1801-1820
1829-1837
1866-1877
1845
1910-1920
1740-1800
1925-1960
1880-1920
1880-1920
1880-1920
1880-1920
1880-1920
1880-1920
1880-1920
1880-1920
1880-1920