PDP 11 gear finally moved

Eric Smith spacewar at gmail.com
Wed Jul 22 21:51:47 CDT 2015

On Wed, Jul 22, 2015 at 9:33 AM, Tothwolf <tothwolf at concentric.net> wrote:
> The only
> thing we could know today is if the capacitor passes industry standard tests
> and if the power supply those capacitors are a part of functions correctly
> when fully loaded.

We built a dummy load for testing the DEC Type 728 power supplies
under four different load conditions (combinations of loads on the two
outputs), and verified that the ripple was within DEC specifications.
The power supplies are retested for voltage and ripple every year.  If
the ESR increased very much, it would result in a noticable increase
in ripple.

Here's an example of the test results which are kept on file:


The majority of the DC supplies in the PDP-1 are Type 728, but there
are a few other types as well, and they were and are tested also.

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