using new technology on old machines. Was: PDP-12 Restoration at the RICM

[tony duell]

> >
> > I am very worried that people would rather use a microcontroller than change
> > a couple of passives. Can't anyone read a schematic and think????
> 
> Nope. I didn't know this hobby required a degree in electrical
> engineering.

Well it had better not. I don't have one

> By your criteria a lot of the rare stuf behind me would be in the
> dumpster because no-one qualified was arround.

Oh come on. You yourself said you are here to learn. This module
is hardly complicatated. OK, it is not obvious what some of the 
waveforms are (which is a good reason to put that board on the
bench -- it will run on its own -- and probe it with a 'scope. Being
an oscillator, all the waveforms are repetitive so _any_ 'scope
will do), but it is farily clear that it is an RC oscillator and that 
the time constant of a particular RC network is going to have 
an effect on the output frequency. So you change the capacitor
and probe with the 'scope again. And so on.

-tony


/P