11/73 (ba23) bringup after 12 years in deplorable storage conditions

Noel Chiappa jnc at mercury.lcs.mit.edu
Thu Nov 20 15:38:12 CST 2014

    > Roe Peterson roeapeterson at gmail.com 

    > I would remove all the boards, blow it out, insert the minimum board
    > set, (CPU, memory, DL console, maybe bus terminator depending on
    > backplane) and just turn it on.

That long in storage, I think that I'd probably go for powering it on with a
dummy load first. It's not _that_ much more work, and it could save some
expensive/rare electronics.

It you don't have any QBUS Minimum Load Modules, get a couple of high-wattage
resistors (down at Radio Slack, if necessary) and rig the equivalent. The
M7556 MLM draws 1A of +5V, and I like to run two for testing. RS sells
10-Ohm/10-W resistors (ISTR they had smaller ones too, but I needed to test a
12V supply, hence the 10-W), so buy four...

Probably a good idea to throw a 'scope on the DC power, too, check for
ripple, etc.


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