Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

any easier way to divide by say 12 or ?

Status
Not open for further replies.

MrDEB

Well-Known Member
using attached schematic, the 555 output depending on switch combo, anything from 95 - 1064 hz.
divide by 10 we get 9.5 - 106hz
at 106 hz the leds would be all on or at least look like it.
thinking a 4013 but trying to keep parts count down.
the 555 circuit is already built. the cub scouts had / having a ball assembling and making "music"
want to add some FLASH
the basic knight rider circuit would do the trick.
any suggestions on simpler way to do this.
even considering a PIC but only justy starting out getting feet wet and knowing basics of SWORDFISH. would like to use a smaller chip (only have used 18F series)
any takers or suggestions.
 

Attachments

  • scout knight rider.PNG
    scout knight rider.PNG
    40.2 KB · Views: 178
Use a 4013 14-bit counter as a divider. You can tap-off whatever divide ratio you want.
 
I think you have the wrong chip?
A 4013 is a duel D flip flop
Wonder if say a 4059 can be subed for the 4017??
 
Yes, somehow I wrote down the part no. the op was using.

The 14-bit counter is a 4020.
 
Got to rethinking this, at the max of 106 hz but that has 10 LEDs flashing as well so at 106hz each led on ,5 seconds??
or is my math wrong??
the 4017s are .35 each but need 2 per board x 15 boards. (need to make more 555 boards as well)
wish Goldmine had the 4017 in stock as I need more switches (100 for $5 as well as 1n4148's $1=100)
They do have a 40174??
 
Whatever counter you use, you need to drive it's clock input from pin3 of the 555 and not from the LED.
 
oups your right. my bad. I connected to wrong side of LED.
in the schematic I failed to remove the 50 ohm resistor connected to pin 3 as well. the unit is not real loud anyway as the speaker is 27 ohms instead of the listed spec of 8 ohms.
now its a matter of cost per part (4017's from Mouser or Allied. need to look at shipping as well. thinking about going with sockets and letting the scouts take all the parts home and assemble. only concern is letting them take the IC's home , what with the IC's being CMOS and then having bent pins etc.
Then the subject of battery consumption. My Metex-11 meter won't read current. The display shows a minus sign and 0.00ma.
any estimate what this circuit will draw?
 
My Metex-11 meter won't read current. The display shows a minus sign and 0.00ma.
You could put a 1Ω 1W resistor in series with the power source and measure the voltage drop across it: 1mV = 1mA, 100mV = 100mA, 1V = 1A, etc.
any estimate what this circuit will draw?
Hard to say, I would guess at around 50-80mA depending on what "note" you hit.
 
Well I got 11 of the 12 boards working.
The 12th board just refuses to work.
Replaced speaker, 555, went over board with fine tooth comb??
the ones that work I have just under 2 volts output. this headach board has 7volts.
Led lights up so I must be getting something out?, yea 7 volts. Checked every pin on the dip socket, power, etc.
my plan is to eth couple more boards and strip this headach board of switches only.
Have no more single sided copper boards so either use double sided or vero board (has bunch of holes already. just need to hard wire everything.
 
Replaced speaker, 555, went over board with fine tooth comb??
I prefer a fine tipped soldering iron, but whatever works for you. :D


the ones that work I have just under 2 volts output. this headach board has 7volts.
Check that pins 2&6 of the 555 aren't shorted to pin 1 (ground).
 
Last edited:
Will double check
hopefully that's it
the board is complete but need to work come monday afternoon.
etched 4 more boards, drilled, cut out.
all ready for populating.
 
Will double check
hopefully that's it
the board is complete but need to work come monday afternoon.
etched 4 more boards, drilled, cut out.
all ready for populating.

hi deb,
For a divide by 12, use a 7492 , its a divide by 12 ic.
 
Am thinking that divide by 10 is adquate seeing how I only go up to 1064hz or there abouts.
divided by 10 =106hz then sending the 106hz into another 4017 with 6 LEDs connected to 10 outputs means each LED is flashing at 17 hz (I think?)
anyway if I use two 4017's I can get a quanity discount. the thing that throws a wrench into the works is the shipping. Mouse and Digikey at least 410+.
looking at Allied. I ran across a box from them and shipping was only $2. need to look at actual bill.
were talking 30 IC's
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top