Re: [beam] Bad news Ben
- Hi William,
> I got the other Cricket circuit working great. The guy I gave it to was:-) Glad to see a happy customer.
> so excited about hi "robot." He even gave me $5 so I could switch out the
> 2200uf to a 1f.
> BUT, the problem is that I have ANOTHER party tomorrow, andI've learnt the hard way that BEAM robots that are intended as presents
> I need another present. I had grand ideas about a mag bot with the FRED
> circuit, but I looks like a no go.
always take three times longer than you thought that they would... this
includes my original dragonfly.
> I've taken a length wire a wrapped itThar be strange goings on in them thar hills....
> around a screw. It's a great magnet just using my battery pack, but when I
> plug it into a FRED engine. It doesn't work. While nothing is connected in
> the motors place the cap voltage hovers around 1.5v. When I stick in the
> inductor where the motor goes, the voltage shoots up to around 2.4v and sits
> there, modulating a bit as the FLED blinks.
OK, first things first. Have you tried a motor instead of a coil? A high
internal impedance cap will behave in this manner, and will not let a
motor fire properly.
Also, what's the resistance of your coil? It should be above, say, 2
ohms, and ideally should be about the same as your motor (typically about
If your motor works fine and the coil doesn't work,
then here's what to try:
Grab a 0.1 uF (or 0.22 or 0.5 uF) cap and stick it in as many different
places as you can think of. Across the coil leads would be a good start,
also try putting it from ground to the FLED, from ground to the base of
the PNP transistor, anywhere that you can think of. This highly
scientific approach can sometimes fix a reluctant circuit. In case you
hadn't already guessed, I don't know what the problem is.
> I don't understand why theWell, since I'm writing this on Monday, I guess you must have already
> inductor would behave any different from the motor. Any hints help or
> suggestions? Oh, well. I guess I can run to the shack and build another
given the present or fixed the problem...
Maybe next time.