Re: Ruby - How about a sight glass?

[Harry Wade]

At 10:24 PM 5/1/01 -0500, you wrote:
>Would it be simpler to light an LED and then it go out when the water
level drops to the low level?  Sounds too simple. Anyone with ideas out there?
>Later,
>Trent

Trent,
     It's not new.  Either Peter Dupen or Roy Amsbury (both 1st medal
winners for locomotives at Model Engineer (London) Exhibitions) described
an electronic water level indicator system in Model Engineer magazine 20 or
so years ago.  If I remember correctly it used insulated backhead sensors,
roughly resembling spark plugs, through detector circuit and LEDS.   The
circuitry was relatively simple.  Whatcha' wanna bet Paul's is an adaption
of that? :-)   I can look up the dates if anyone is interested.  The
problem might be, as I have runn into before, that the transistors called
for in the circuits are now long obsolete and discontiued.

Regards,
Harry Wade
Nashville, Tn