[Test-Equipment] Re: H-P 400 series, addendum

[Gary Chatters]

>
>Gary, under the heading of "no good deed goes unpunished" I'll have to
>admit that I just don't remember.  ;<)

Isn't that terrible.  You go to all that work and then somebody says:
Could you just do one more thing.  :-}

>All of the tube versions have a ground-referenced input and a grounded
>case, so if one needs to measure an elevated signal it's necessary to
>'float the boat' with a ground buster.  CAREFULLY!

Since the F/FL/GL models have the binding posts it just seemed like
they ought to have a floating input.  I finally went to the effort
and found a schematic for the 400GL which indicates that the 
lower/black binding post is at chassis/power safety ground and thus
is not floating.  Then I did the obvious thing and checked a 400F
with an ohm meter and the black binding post is 0 ohms to the chassis
and the safety ground pin on the power connector.

It seems to me that a floating input would be very useful for
metering balanced audio lines.  But that apparantly was not their market.

Thanks again for your previous efforts on this.

Gary