Hi all. I'm also stuck on the following

a row of 8 green LEDs (bi colour with RED).
To start with, the last LED is red
moving a rheosat will turn this green, and the 7th red
continuing to move the rheostat will make the 6th red, and put the 7th back to green
etc

Currently I have a set of 16 comparators and 8 NAND gates and a heck of a lot of resistors and transistors to stop things blowing up. I feel certain there must be a standard circuit for this which is better than mine.

Help much appreciated ^_^ xxxxxxxxxxxxxxx

 

Originally posted by dave_is_sexy@Apr 25 2005, 09:31 AM
Hi all. I'm also stuck on the following

a row of 8 green LEDs (bi colour with RED).
To start with, the last LED is red
moving a rheosat will turn this green, and the 7th red
continuing to move the rheostat will make the 6th red, and put the 7th back to green
etc

Currently I have a set of 16 comparators and 8 NAND gates and a heck of a lot of resistors and transistors to stop things blowing up. I feel certain there must be a standard circuit for this which is better than mine.

Help much appreciated ^_^ xxxxxxxxxxxxxxx

[post=7236]Quoted post[/post]​

hi

you can do it with a CD4017. have the output ORwired with 1N4148.