What do you think of the 465B scopes?


The later 400 series, say, the 465, 475 and 485 are all good scopes.

The 485 is the most complicated, and the best performing.

The switching power supply is one problem area in the 485, with the tantalum
caps therein being the problem. Replace suspicious caps with MIL-Spec tants.

Usually, these caps fail in short-circuit mode, and this will trip the 485s
super-complicated overload detection circuit (an 11-input OR-gate), which not
only monitors the power supply itself, but the HV and beam sections as well.

Use gen-u-wine TEK probes, and you will not regret it.

When forced to, I would ... reluctantly ... use our de-facto standard HP 1725A,
but only with TEK probes. The HP probes were so unstable that one couldn't
reliably tune the clocks on our mainframes to the required sub-nanosecond skew.