FreeLists / az-observing / [AZ-Observing] Re: No lasers at Bryce Canyon

[Joe Larkin <joeclarkin@xxxxxxxxx>]

> This  may sound complicated, but the easiest way to do this is to
> use a set
> of  not-quite-fresh  batteries.   This also happens on colder
> evenings when
> the laser and batteries do not operate as efficiently.  I believe
> it may be
> possible  to  make a small disk of a low-resistance material, about
> 1/8" to
> 1/4"  thick  and  the  same  diameter as a AAA or AA battery, that
> could be
> inserted  in  series  with the batteries, thus limiting the current
> and the
> laser's  output  power.  This material would have a very low
> resistance, of
> maybe  just  a few tenths of an ohm.  I'll see what I can come up
> with, and


Use a piece of unetched double sided circuit board. Cut a small round
piece about the diameter of your batteries. The copper on one side is
isolated from the other side by the board material between them.

Solder a low value pot to two wires, then solder one wire to each
side of the board. Put the board between two batteries in series or
between a battery and a battery terminal in the laser. 

Adjust the resistance with the pot to control the brightness. 

Joe Larkin

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