Console on Symbolics LISP Engineering

XL1201 Power Consumption

Sun, 26 Jun 2016 21:32:29 +0000

I was asked how much power is used by the XL1201. Here are a few data points…

XL1201 with only SCSI2SD: 222-233W
Console: 106W

With the XL1201 sitting idle it takes the same amount as calculating (fib 36), so apparently the CPU is running at a constant speed at all times.

When the console goes into sleep mode (after 20 minutes by default), power usage doesn’t appreciably drop.

Console sleep mode: 105W

With the XL1201 running a 15,000 RPM Seagate Cheetah X15 drive (ST318451LW), it doesn’t really take all that much more power.

Console Internals

Sat, 25 Jun 2016 18:09:57 +0000

This is a Symbolics Model PE36-PCONS, Part No 365404 Rev C console. My serial number is 21811. (“There are many like it, but this one is mine.”) An album of detailed internal photographs is available including full size versions of all the below images.

The console seems to be in good shape, with all electrolytic capacitors intact (not bulging or leaking). I should probably test the power supply outputs as there are trimmers for the voltages to adjust them.

Console Monitor Adjustment

Sat, 18 Jun 2016 15:49:39 +0000

There are 10 controls for monitor adjustment. Two large finger controls, a group of 6 small multi-turn trim controls for vertical, and a group of 2 small multi-turn trim controls for horizontal.

You can access these controls by unscrewing the four screws at the back of the monitor and sliding out the rear panel. They will be at the right side (looking at it facing the screen).

I’m not sure what exactly all of these do, and don’t have any manuals about them, so if anyone knows what they do I’d welcome the information. (Try me using symbolics at the last two parts of the domain name of this site.)