It's time to restore the 11/45.

Marc Howard cramcram at
Thu Feb 5 12:24:15 CST 2015

Where do you guys find these 11/45's?   I'd love to get one someday.  Is
there an PDP-11 outlet mall I missed somewhere?


On Thu, Feb 5, 2015 at 9:46 AM, Jon Elson <elson at> wrote:

> On 02/05/2015 10:27 AM, Noel Chiappa wrote:
>>      > From: tony duell
>>      > A plain Variac does not provide isolation from the mains so you are
>>      > actually now working on mains-connected circuitry (read :
>> dangerous and
>>      > you can't clip a 'scope on it).
>> I'm clearly a little slow this morning: why can't you use a 'scope on it?
>>  Because the equipment under test is connected to the mains.  A bridge
> rectifier is
> between the AC input and the rest of the circuitry, therefore there is no
> part
> of the EUT that is at neutral potential, and if you hook up a grounded
> scope, you
> will have fireworks.  Floating a scope above ground should be reserved for
> the
> most special cases where you are testing line-powered gear that MUST not
> run on an isolation transformer, for some reason.
> Jon

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