Alt-BEAM Archive
Message #01390
To: JVernonM@aol.com
From: Steven Bolt sbolt@xs4all.nl
Date: Tue, 9 Mar 1999 09:38:21 +0100 (CET)
Subject: [alt-beam] Re: diagnosis please
On Mon, 8 Mar 1999 JVernonM@aol.com wrote:
> I have noticed a problem with Virus, one of my symets. He kicks
> beautifully until placed in direct sun, then he seems to "lock
> up" and do nothing after the first pop. If I place my hand over
> his solar cell for a second or two, then remove it, he will kick.
> He has no trouble working in subdued light. I have noticed that
> if he is placed very near my halogen desk lamp he will fire in a
> long, extended burst that seems to fade away, then nothing until
> I play peek-a-boo again. He has a 1381-N trigger, the 37x33 solar
> cell, 1 4700uF cap, and a walkman motor. My bouquet has the same
> arrangement save one more cap and it spins like crazy in full
> sun.
I suspect that whatever you use to latch the on-state is
oscillating. At lower light levels there isn't enough power to keep
the oscillation going, so you don't notice the problem there.
A common cause is the small recorder motor with the built-in cap.
A somewhat more elaborate latch can be made oscillation-proof, more
or less, but I guess you don't want to add components. That leaves
another motor as the obvious remedy.
Btw: Nothing beats a good oscilloscope to check such things...
Best,
Steve
----------------------------------------------------------------------
# sbolt@xs4all.nl # Steven Bolt # popular science monthly KIJK #
----------------------------------------------------------------------
------------------------------------------------------------------------
eGroup home: http://www.eGroups.com/list/alt-beam
Free Web-based e-mail groups by eGroups.com
Home