OK, guys, it's been a darn long time since I tinkered with chips, more like 20 or more years ago. I'm retired now, but I need to build a little device.
I can't get my head on straight about this and remember what chips would do it simply.
What I need is a circuit that will sequentially turn on three LEDs, for about 0.5 seconds and an off period of the same duration and then repeat.
There is one chip that would sequence, like one of ten, and a way to make it loop and limit to four, but it's just not coming to mind.
I'd prefer to use chips that I can get at Radio Shack and TTL or 54/74 series preferred.

Maybe a 555 timer as a clock.
Thanks in advance!
Gerry

 

Hello,

Have a look at the posts #10 and #12 of the following thread for some ideas:
https://forum.allaboutcircuits.com/threads/leds-555s-flashers-and-light-chasers.19075/

Bertus

 

OK, guys, it's been a darn long time since I tinkered with chips, more like 20 or more years ago. I'm retired now, but I need to build a little device.
I can't get my head on straight about this and remember what chips would do it simply.
What I need is a circuit that will sequentially turn on three LEDs, for about 0.5 seconds and an off period of the same duration and then repeat.
There is one chip that would sequence, like one of ten, and a way to make it loop and limit to four, but it's just not coming to mind.
I'd prefer to use chips that I can get at Radio Shack and TTL or 54/74 series preferred.
View attachment 129465
Maybe a 555 timer as a clock.
Thanks in advance!
Gerry

 

OK, guys, it's been a darn long time since I tinkered with chips, more like 20 or more years ago. I'm retired now, but I need to build a little device.
I can't get my head on straight about this and remember what chips would do it simply.
What I need is a circuit that will sequentially turn on three LEDs, for about 0.5 seconds and an off period of the same duration and then repeat.
There is one chip that would sequence, like one of ten, and a way to make it loop and limit to four, but it's just not coming to mind.
I'd prefer to use chips that I can get at Radio Shack and TTL or 54/74 series preferred.
View attachment 129465
Maybe a 555 timer as a clock.
Thanks in advance!
Gerry

Most Radio Shack stores are closed now. If you have a few days, you can order from Digikey.com and select "first class mail" and your shipping/handling will be the price of one chip at Radio Shack and each chip will be about 1/4 the price of radio shack.

You need a decade counter and have the fifth pin reset the counter as EM Fields shows above.
A CD4017 is the original and now 74HC4017 or any variant thereof will meet your needs.

An NE555 or any different 555 variants will meet your needs as the pulse train.

 

EM - My interpretation of post #1 is that there is no off time between LEDs lighting up. Q0, Q1, and Q2 to the LEDs, skip Q3 for the off state, and tie Q4 to reset. If I'm right, there is no need for a 49.9% duty cycle from the 555; R1 can equal R2.

ak

 

Hello,

Have a look at the posts #10 and #12 of the following thread for some ideas:
https://forum.allaboutcircuits.com/threads/leds-555s-flashers-and-light-chasers.19075/

Bertus

Great Info, Thanks, like I said it's been a long time. About 20 years ago I designed a printer adapter for the govt that simply changed a 7-bit parallel to an 8-bit parallel printer interface, (Centronics standard), the big thing was the trick to delay the timing by running it through a few 7414's to delay the sync/clock to make it work. Saved them close to 3/4 mil the first year. Most of the stuff after that was just designing, building and writing procedures for simple test fixtures that used switches to load/program the UUT. Now, after retirement from the govt, I just fix slot machines on the casino floor for a local casino.

 

Most Radio Shack stores are closed now. If you have a few days, you can order from Digikey.com and select "first class mail" and your shipping/handling will be the price of one chip at Radio Shack and each chip will be about 1/4 the price of radio shack.

You need a decade counter and have the fifth pin reset the counter as EM Fields shows above.
A CD4017 is the original and now 74HC4017 or any variant thereof will meet your needs.

An NE555 or any different 555 variants will meet your needs as the pulse train.

I ordered the chips from Jamco, also some voltage regulators to power the wife's candles instead of batteries. I have about 150 wall-wart 50 mil 9V power supplies that I can use for those.

 

From digikey's terms and conditions:

When a check or money order accompanies your order, Digi-Key pays all shipping and insurance (our choice for method of shipping) to all addresses in the U.S. and Canada.

 

View attachment 129469

That's just about what I need! Thanks! I ordered some chips from James Electronics Ltd. (Jamco) not too long ago. When the chips get here and I have the little project finished, I will post the info on it.