Alt-BEAM Archive
Message #05065
To: beam@sgiblab.sgi.com
From: Steven Bolt sbolt@xs4all.nl
Date: Wed, 7 Jul 1999 08:00:10 +0200 (CEST)
Subject: [alt-beam] Re: Something funny with the 1382 voltage triggers?
On Tue, 6 Jul 1999, Bob Shannon wrote:
---8<---
> Now that we are all brushed up on the circuit theory, and
> failings of BEAM as a teaching tool, would anyone care to look at
> the actual problem?
I for one am not going to do any more of that. The 2-transistor
latch/driver isn't interesting, it isn't much good in this
application, and it is still usually shown with a 3904 as driver,
which just isn't the right transistor to drive a motor with.
If BEAM made any progress at all - as an entry level hobby - the
2-transistor latch/driver would have been thrown out long ago. It
doesn't help people, it bothers them, and teaches little except the
wrong things.
Can you do better? Sure. Separate latch and driver. Then make sure
that your latch switches off properly (at well above 0.7V), or use a
monostable instead of a latch; that's more appropriate for most SE
applications.
Best,
Steve
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# sbolt@xs4all.nl # Steven Bolt # popular science monthly KIJK #
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