>> 1. no freewheeling diodes?
>
> Small DC motors can be very noisy electrically. I'd be wary of EMF
> interference to nearby logic\

I'd be aware of *damaging* nearby chips!

>> 3. which component determines the base currents? the impedance of
>> the driving source, or the ohmic impedance component of the LEDs??
>
> As it was (IIRC, I saw it a couple of weeks ago) using a PICAXE,
> then the max source/sink would be that of whatever PICs are used
> as PICAXEs, 20-25mA. I guess that would be why Darlingtons

for the first stage (and even then it would be very bad practice). but=20
the second stage is slaved to the low-impedance output of the first.

>> 5. over which voltage range does this work? and for which brands and
>> colors of LEDs? and over which temperature range?
>
> Presumably a 6-pack of NiCds, and green (as can be seen in the photo)

Did he test it during other phases of the moon?

--=20

Wouter van Ooijen

-- -------------------------------------------
Van Ooijen Technische Informatica: www.voti.nl
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docent Hogeschool van Utrecht: www.voti.nl/hvu

--=20
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