Could use assistance on a timer project

[warlc]

there is another 100uf cap that was in the original ciruit i think it was to filter out any spikes. it goes from vcc to ground. the cap on the left (in the photo) goes from ground to 10k resistor to 1k resistor to pin 7 on 555. there is a green wire that i have from pin 4 to an unsed line i was using that for the pin 4 to vcc connection. i put the jumper back from 4 to 8 so that , when energized , the timer would start but that doesn't work either. i'm lost

 

[warlc]

i think i'm going to quit for the night. i really would like to thank you guys for trying to help me out. i'm going to go back to the basic 555 circuit and go from there (tomorrow) thanks again

 

[warlc]

problem found

i found the problem with the timer, there should have been a jumper from pin 2 to the 100uf cap from pin 7. it works fine but it is very sensitive to retriggering. i just have to touch the wire on pin 4 and it rertriggers. where can i add caps to filter this out. i know it will get worse when my actuator is hooked up because it will spike the voltage like a solenoid does.

 

[duffy]

That was the one.

Put a .001µf cap from pin 4 to ground if the retriggering looks like it could be an issue. Are you running long wires to the opto on the clock, or is the music box very close by?

 

[warlc]

the wires won't be no more than 6" long. i was planning to run from the timer ciruit to the music movement with a 4wire phone jack and plug. (see photo of prototype and back of cabinet)
Im hoping i'll get the opto sensors this week so i can put it all together.

 

[duffy]

That looks terrific! I'm digging that ship on top. Does the music box play nautical tune?

 

[warlc]

yes, it plays "over the waves" or "anchors aweigh" but my idea for these clocks is that the scenes can be changed (along with the music) you can have a winter ,summer, ship with lighthouse etc. and they are "animated"
the ship "sails". cool huh?

 

[duffy]

Yes, very cool! I was HOPING you would say the ship was animated!

The lighthouse one sounds especially nifty. Put a CDS cell on it so the lighthouse light comes on in the dark.

 

[warlc]

you're getting the idea! but i'm very limited in electronics (but not imagination)
how about a pic logic. i could have a ship (i can make "bigger" ones) that's sailing then, all of a sudden, it gets dark and a storm comes (ship sails faster) lightning in the background, led display (sound chip "thunder") or a pirate ship (guns fire) crew "works" "sing sea chanties etc.
but first i have to learn how to build a "simple" timer (i'm a quick study)
hey thanks to your help i have that almost completed and i really appreciate yours and everyone elses help
thank you

 

[warlc]

it appears that i'm not out of the woods yet. when i turn the circuit on and bring pin 4 to vcc the 555 continues to time until i shut it down. i thought it was spikes retriggering the timer, but i think it is the way the pause is wired in with the diode, but i don't know how to change it. how can i edge trigger it so that it will only respond to a change in voltage?

 

[duffy]

Like 1 second on, 24 seconds off? Isn't that what you wanted?

 

[warlc]

yes that is , but i want it to happen once every hour. the timer isn't a one shot the way it's wired. if the opto senses the clock chime then triggers the timer though pin 4., it should pause for 24 secs then a one second pulse. then it should reset and wait for the next hour to start the cycle again.
the way its wired now the timer will continue to time 24 sec then 1 sec
even after the flag on the opto moves and resets the transistor. right?

 

[duffy]

No, after the flag moves it should go off and stay off. What voltage do you measure on that trigger pin when the flag isn't in the opto?

 

[warlc]

i don't have the opto yet, i was running a jumper from pin 4 and momentarily touching it to vcc

 

[duffy]

Don't do it that way. It has to be connected to Vcc or ground. The opto circuit will do that.

 

[warlc]

so i have to wait till i get the opto or can i simulate it somehow?

 

[duffy]

1. Connect it to that 100k resistor to Vcc like in the circuit.

2. Hold it on ground like the opto does when the flag's not there and the light turns the transistor on. Circuit should be off.

3. Let it off ground to simulate the opto transistor shutting off. When the flag blocks the light, the transistor turns off, and the 100k resistor pulls the line up to Vcc automatically. The timer should start operating.

 

[warlc]

ok , what i did is wire a line from vcc to 100k resistor then to pin 4 then a jumper to ground. turned it on, circuit is off. i pulled out the ground jumper and the timer should start timing. as soon as i pull the jumper out it fires the relay , it should pause 24 secs then fire the relay. it doesn't keep
running though so that's okay.

 

[warlc]

it is working. i tried it 3 or 4 times. i'm getting spikes because of the way i'm using the jumper, but it works. my timing changed from 24 sec. to 17 secs.
why is that?

 

[warlc]

this circuit is not going to work for me. It becomes an astable timer when pin4 is removed from ground. I breadboarded another circuit which has an edge trigger on pin 2. it will time out even with pin 2 held to ground. this will work with the opto sensor (because of the long reset time). but i have two problems with it. It turns "on" the relay for 24 secs and there is no pulse of 1 sec. and i need to bring pin 2 to ground to trigger it. How do i wire this from the opto?