Re: Need help with intermittent circuit failures - JK Flip Flops

Hi guys,

*** As requested, I have posted a schematic under
alt.biniaries.schematics.electronic newsgroup (as an attachment).
It will be titled: "Schematic ref 'sci.electronics.basics' thread dated
6/6/06" ***

Please continue to post under here and not the other newsgroup.

John, I have added the two parallel caps directly across the 555's power
supply (pins 1 and 8) as you suggested, and it *does* seem to work a lot
better now... thank you.

I accidentally blew a transistor that powers up the motor because the 1 sec
delay didn't happen for some reason, where the motor was spinning in one
direction, then all of a sudden it changed to the other direction without it
stopping. The transistor fried. I was wondering if there is any way of
preventing the transistor from getting damaged should this happen again.
I'm not sure how to do this.

Also I am pretty sure I am missing something around the motor ... diode?
caps? I have very little experience with motors.

I know you guys are probably asking yourselves why I did this and why didn't
I do this, etc. but I am still learning. =) I only do this as a hobby.

Thanks again
Jason.


.

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