RK07 repairable?

From: Andreas Freiherr <Andreas.Freiherr_at_Vishay.com>
Date: Mon Jan 20 05:05:55 2003


expect a little more here: the transformer in a PDP-11/34 feeds up to
four bricks (depending on whether core memory needs the 20V supply, or
whether battery backup is present) and some small scale stuff, and each
of these bricks does about 150W or more of _output_ power (e.g., 20V/8A,
5V/32A, 15V/10A, ...).

So, with a combined output of more than 600W, I'd expect the transformer
to do something like at least 750VA. Even more, considering its
weight... ;-) - If you need to lift the box without help, grab it from
the back side, where the transformer is.

Talking about power supplies in the 11/34: the power distribution board
was modified when the 5V/32A regulator bricks were introduced because
the original version couldn't handle the current: it was designed for
the former 25A bricks. I don't have the part numbers at hand right now
(they're on microfiche at home), but can look them up if you need them.

Just in case: I seem to remember that there are several of those bricks
sleeping in a dark corner of my basement, so if you have no luck fixing
yours, let's try to make a deal. Good luck anyway!


Jochen Kunz wrote:
> On 2003.01.17 20:35 Tony Duell wrote:
>>The DEC 'bricks' -- the H744, etc, regulators -- used in the 10.5"
>>PDP11/34 box are relatively friendly to work on. They are swtichers,
>>but they start from a 30V AC input (from a large mains transformer --
>>an isolating transformer).
> The owner showed me already a big transformer (should be around 200..400
> VA) from the PSU. He also said that the PSU is modular and one of the
> modules is broken. An other reason why I an expecting a /34.

Andreas Freiherr
Vishay Semiconductor GmbH, Heilbronn, Germany
Received on Mon Jan 20 2003 - 05:05:55 GMT

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