PDP-8/E PowerSupply Part 2 - test-drb@ccmp.vtda.org

29 Nov 2001

Interesting, I've got the lamps (I'd been hoping for LEDs), but I didn't
connect the wires for testing.  Looks like the next step when I get home
will be to figure out which wire plugs into which connector on the front
panel.  Unfortunatly the person that took the system apart and shipped it
didn't make notes.  OTOH, he did a magnificent job of packing and the system
came with full doc's.

			Zane

...

 If memeory serves that depended on the lamps to load the PS
 down to rated voltages.  If you have leds the load willbe lighter and since
 they have current limiting resistors the small extra votage is not an issue.

 Allison
 -----Original Message-----
 From: Zane H. Healy &lt;healyzh(a)aracnet.com&gt;
 To: classiccmp(a)classiccmp.org &lt;classiccmp(a)classiccmp.org&gt;
 Date: Thursday, November 29, 2001 2:57 PM
 Subject: PDP-8/E PowerSupply Part 2

 OK, I got brave and flipped the switch and started
testing voltages with
everything disconnected.

I've got a H724 PS and everything looks good except the +8Vdc line which is
for powering the light bulbs on the front panel, and the 14Vac.  The +8Vdc
should be between 6-10Vdc according to Volume 1 of the maintenance manual,
and it's currently at 11.14Vdc.  The 14Vac looks like it might be even more
messed up, as I'm getting 8.95Vac on one line and 19.26Vac on the other,
but it doesn't look to be used.

Now for everything except the +8Vdc and 14Vac everything looks to be
adjustable.  So, is there anything I can tweak on this, or should I just
not worry about it?  I really don't want to be blowing lightbulbs if I can
help it.

 Zane
--
| Zane H. Healy                    | UNIX Systems Administrator |
| healyzh(a)aracnet.com (primary)    | OpenVMS Enthusiast         |
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