Differences Between The Tektronix 2235 or 2235A

I was thinking about purchasing a used Tektronix 2235 or 2235A and would like to know what are the differences between the 2 versions.

2235
Dc to 100 MHz bandwidth
2 mV sensitivity
Advanced trigger system
5 ns/div sweep rate
Delayed sweep measurements
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2235a
100 MHz bandwidth
2 mV - 5 V/div sensitivity
Advanced trigger system
B sweep time base 50 ns/div to 50 ms/div
Rise time 3.5 ns
Color CRT

Thanks for the info. I did some more sarching on the web and someone stated that they may have made some improvements to the power supply.