🚀 go-pugleaf

In article <1495@frog.UUCP>, john@frog.UUCP (John Woods, Software) writes:
> Does anyone (a) know where I can get a Magic Eye tube (if they are even still
> made), and (b) have information on how to use them (required voltages, etc.)?
> 
> Believe it or not, I want to use this "stab from the past" to indicate
> CPU usage on a computer -- I specifically wanted something disturbingly
> anachronistic (a meter came in second place...).

	Yup, those tubes sure are an anachronism!  Some people I knew called
them "Cat's Eye" tubes.
	What you want is a type 6E5 manufactured by RCA.  Newark Electronics
(Chicago, IL) still has 'em in their catalog for $ 27.50.  You can probably
find them for less money in surplus stores or some mail-order companies
which specialize in the sale of vacuum tubes.
	There is also a 6U5, which is similar to the 6E5.  About 10 years
ago, an industrial electronics distributor that I deal with was doing some
housecleaning of ancient inventory and gave me a 6E5 along with a mounting
assembly made by Amphenol which was specifically used for panel mounting
(it has a nice Art Deco escutcheon plate :-) ).  I took the 6E5 and mounted
it in a small box as a conversation piece.  I built a DC-DC converter using
a Triad toroidal transformer to provide 250 volts DC @ 0.025 amperes from a
12 volt plug-type power supply.  I used a function generator IC with an op
amp to give me a triangular wave with an amplitude of 8 volts - necessary for
"full scale" deflection.
	The completed device "winks" when turned on, and has adjustable
wink "rate" and "depth" controls.  Talk about an anachronism of components
in that box!
	You will need 200 to 250 volts DC at 0.025 ampere maximum, 6 volts
AC or DC @ 0.3 ampere for filament, and your "deflection voltage" will range
from 0 to -8 volts for 0 to 90 degress deflection.

	I highly recommend this tube as an exercise in anachronism!

<>  Larry Lippman @ Recognition Research Corp., Clarence, New York
<>  UUCP:  {allegra|ames|boulder|decvax|rocksanne|watmath}!sunybcs!kitty!larry
<>  VOICE: 716/688-1231        {hplabs|ihnp4|mtune|seismo|utzoo}!/
<>  FAX:   716/741-9635 {G1,G2,G3 modes}    "Have you hugged your cat today?"