On Sun, 24 Jan 2016 16:02:14 -0600 (CST), you wrote:
While the power switch is the same, keep in mind that the main board inI consider them separate designs with the 2213/2215 (1982 to 1985)
being the beta test for the series which starts with the 2235/2236
(1984) and includes the 2213A/2215A (1986) as replacements for the
2213/2215. Besides differences in the overall design, the 2213/2215
has a 30pF input capacitance and 10kV acceleration while all of the
later models have a 20pF input capacitance and 14kV acceleration.