pdp-8/e restoration.

Jon Elson jonelson126 at gmail.com
Fri Aug 4 08:43:22 CDT 2017

On 08/04/2017 02:24 AM, Rod Smallwood via cctalk wrote:
> Programmers console is in its slot. Bad bulbs (not LEDs)  have been 
> replaced
> Power up and all the lamps come on either bright or dim (off) except 
> the RUN light.
> So questions:
> 1. Should the run light glow dimly?
Probably all lights should glow very dimly.  DEC put a resistor across 
the transistor to put a slight warming current through the bulb.  This 
reduces shock to the filament every time it is turned on.
(This info is from other DEC machines, not PDP-8, but I'm pretty sure 
they would do the same there.)


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