Help - needed - time delay relay - 12vdc

iONic

Joined Nov 16, 2007
1,662
wow....Thanks for all the input guys.
Time for some shopping now I think. Any good shops in the uk sell these parts...maplins?.....digikey?.....
Have you decided what you were doing with three LED's? Clumping them together? Perhaps one as a power indicator so you don't forget to turn the device off, one to light up when the time has elapsed. I will need to alter the circuit and perhaps the series limiting resistor depending on the use.
 

Thread Starter

billy breach

Joined Jul 31, 2011
48
I think I'll keep it easy for me and have one led as the power indicator. As per the drawing. Can you suggest a decent breadboard to use. One you solder and use solder to connect the holes? Or should I use a solderless breadboard with jump cables.or another type of method?
 

iONic

Joined Nov 16, 2007
1,662
I think I'll keep it easy for me and have one led as the power indicator. As per the drawing. Can you suggest a decent breadboard to use. One you solder and use solder to connect the holes? Or should I use a solderless breadboard with jump cables.or another type of method?
The LED in the drawing is turned on only when the alarm is sounding, but using it as a power indicator would be more beneficial.

I prefer to use proto boards that have copper pads and solder components, but it's up to you really.

This board could be used to test your circuit out. Some people keep the circuit as a final work, but I prefer not to.
Solderless Breadboard

This Ptototype board is identical to the above so the wiring would match up and is a more permanent solution. Too many mistakes and the board and/or components get ruined. Depends on your experience.
Prototype Board

I might also recommend a 8-Pin Dip socket for the IC. The part below is a 24-Pin socket.
Dip Socket

 
Last edited:

1ofakindwork

Joined Jul 27, 2011
58
Now I feel bad about adding my ideas, so to make up for it I subtracted them...Sorry for the intrusion...I now understand this is a place for technical help not for adding my ideas...
 
Last edited:

iONic

Joined Nov 16, 2007
1,662
Now I feel bad about adding my ideas, so to make up for it I subtracted them...Sorry for the intrusion...I now understand this is a place for technical help not for adding my ideas...
The ideas related to the members project are always welcome. Asking questions unrelated to the topic is what would be classified as hijacking.

For what software to use for posting schematic drawings, there are all sorts of paint programs that people use to cut and paste, draw lines, etc. I copied a image from the web and manipulated it in Paint Shop Pro, a program that is now owned by Corel. Others use Electrical CAD programs such as Eagle, multi-Sim to
create schematics.


I could use a red led for when the buzzer sounds and just add a blue led after the on/off switch? with a 470Ω resistor?
Not a problem.

I was just in the supermarket today and saw a electronic stove timer for $5.
All you do is press a button for Hours, another for minutes, and press a third to start. The output of course is a small audio device. It would be easy to just use that audio output to bias a transistor that would cause a higher voltage to a much louder Piezo alarm. Add a 9V battery and the piezo from an old smoke alarm and your done! All of it could be placed in a single package for use.

Just thinking to myself... wouldn't want to stop you from have some electronics assembly fun!
 
Last edited:

Thread Starter

billy breach

Joined Jul 31, 2011
48
iONic,

I'm actually looking forward to make this circuit now..after, all the discussion and research and help from you guys, buying one wouldn't be the same fun. LOL. Of course i've still got the fun of making the "fake bomb" out of UPVC pipe etc for "airsoft" fun. I may also use some plastic tubs etc to fit the circuit board into and the tube to slide the batterys into it.
 

Thread Starter

billy breach

Joined Jul 31, 2011
48
I sthe DIP socket only required if im not using the LM555CN and using the surface mounted version?

Also I see that some POT's have three pins and others two. I take it it gets wired up by passing the middle pin/contact? (for three pin/contact verions)

:eek:
 

iONic

Joined Nov 16, 2007
1,662
I sthe DIP socket only required if im not using the LM555CN and using the surface mounted version?

Also I see that some POT's have three pins and others two. I take it it gets wired up by passing the middle pin/contact? (for three pin/contact verions)

:eek:
The DIP Socket is really to save you IC from frying up when you solder it to the proto board. You solder the Socket id and then then when all the soldering is done just plug the IC into the socket.

2 Pins(Rheostat)
his type of variable resistor with 2 contacts (a rheostat) is usually used to control current. Examples include: adjusting lamp brightness, adjusting motor speed, and adjusting the rate of flow of charge into a capacitor in a timing circuit.

3 Pins(Potentiometer)
This type of variable resistor with 3 contacts (a potentiometer) is usually used to control voltage. It can be used like this as a transducer converting position (angle of the control spindle) to an electrical signal.

Either is O.K. but I usually get the 3 Pin Pot. The connection would be from either end and the center pin. Which end pin you choose determines how the resistor functions, increasing or decreasing resistance with a clockwise turn.
 

Thread Starter

billy breach

Joined Jul 31, 2011
48
I see thanks for that.

How would you know what end pin to wire it up is it just a case of wiring it and seeing what happens? Thats a good idea about the 8pin holder. I take it, that the DIP holder only works with the surface mount versions of the LM555?

Also will a NE555N timer work the same as a LM555?

I've been looking for a 250k POT but can only find short POT's for guitars. I'm looking for a POT that a knob can be placed over the top (for my fake airsoft bomb). Can anyone provide a link to a site where I could find this?
 
Last edited:

iONic

Joined Nov 16, 2007
1,662
I see thanks for that.

How would you know what end pin to wire it up is it just a case of wiring it and seeing what happens?
If you place an ohm meter to the center and one end, then turn the POT and you will know if the resistance is increasing as you turn clockwise(longer time delay). If it's resistance decreases while turning clockwise then you would use the other end pin.

Thats a good idea about the 8pin holder. I take it, that the DIP holder only works with the surface mount versions of the LM555?
Nope. Just the opposite, the surface mount means just that, mounted on the surface.


Also will a NE555N timer work the same as a LM555?
Yes.
I've been looking for a 250k POT but can only find short POT's for guitars. I'm looking for a POT that a knob can be placed over the top (for my fake airsoft bomb). Can anyone provide a link to a site where I could find this?
Digikey:
250K Linear Pot

 
Last edited:

Thread Starter

billy breach

Joined Jul 31, 2011
48
whst the best way to connect these parts on the protoboard?



when I have my power leads coming into the protoboard, is the only /best way to join the parts together by using small wires or and solder across the holes be good enough? I prob wil just use small cables cut to each part just wondering if solder can join the parts together but wasn't sure if this is not a valid way/ not acceptable to do?
 

iONic

Joined Nov 16, 2007
1,662
whst the best way to connect these parts on the protoboard?



when I have my power leads coming into the protoboard, is the only /best way to join the parts together by using small wires or and solder across the holes be good enough? I prob will just use small cables cut to each part just wondering if solder can join the parts together but wasn't sure if this is not a valid way/ not acceptable to do?
Should I assume that this is the style of prototype board you have or are intending on ordering?

How much experience do you have soldering? It might be better to use a solder-less breadboard. Errors can easily be undone. It not the type of circuit that will suffer in performance from assembling on this type of board.
 

SgtWookie

Joined Jul 17, 2007
22,230
That looks like a Radio Shack proto board.

You might find it handy to use PEBBLE breadboard layout tool to plan your protoboard.

Links to it are here:
http://www.rev-ed.co.uk/picaxe/software.htm
about 2/3 of the way down the page.
Better to download the .zip file and use it offline, as if your Internet connection drops while you're working, you will lose your design.

I suggest that you don't keep the 250k pot in there permanently. Lay it out on a breadboard, and get the timing correct using the pot. Then measure the resistance of the pot, and replace both the pot and 750k resistor with one fixed resistor. This will make it much more rugged and reliable.

Laying it out on a breadboard first will help you to make certain that everything is working properly. If you just try to solder everything from the beginning, you may wind up with hard-to-solve problems.
 

Thread Starter

billy breach

Joined Jul 31, 2011
48
thanks for the link to that protoboard designer.

As for the protoboard I had that one lying around in the shed, but i've ordered the one iONic suggest, the points are connected and will be alot easier when soldering. Also I've order a 8 pin ic holder, to prevent the lm555 from frying.
 

iONic

Joined Nov 16, 2007
1,662
thanks for the link to that protoboard designer.

As for the proto board I had that one lying around in the shed, but i've ordered the one iONic suggest, the points are connected and will be alot easier when soldering. Also I've order a 8 pin ic holder, to prevent the lm555 from frying.
Here is the breadboard layout, which may be comparable with the proto board you ordered.



Verify anyone please!

Pebble file txt:
IC||389|270|1|LM555CN|U?|||DIP8|IC||DIP8_1
Wire||396|104|21||11|#FF0000|2|11|||
Wire||369|104|21||11|#FF0000|3|11|||
Wire||369|269|21||11|#FF0000|3|11|||
Wire||371|377|11||11|#FF0000|4|11|||
Capacitor|.01uF|507|367|1|Capacitor|C?||1|1|||cap_111
Wire||504|269|21||11|#000000|3|11|||
Wire||558|462|21||11|#000000|2|11|||
Wire||585|462|21||11|#000000|2|11|||
Capacitor|330uF|534|226|1|Capacitor|C?||1|2|||cap_211
Wire||479|240|11||11|#000000|1|11|||
Wire||452|212|11||11|#CC6633|3|11|||
Wire||585|269|21||11|#FF0000|3|11|||
Wire||425|240|11||11|#000000|1|11|||
Wire||344|405|11||11|#FF0000|3|11|||
Capacitor|10uF|291|422|3|Capacitor|C?||1|1|||cap_113
Resistor|100|265|372|1|Resistor|R?||2||IC||
Wire||261|269|21||11|#FF0000|3|11|||
LED|0|209|421|1|LED|LED?|4|||IC||led_41
Switch||850|183|4||SW?|2||2|Switch||switch_224
Note||944|205|1||||1||To + Batt||NOTEPAD_11
Transistor|BC559|721|388|2|Transistor|Q?|||1|IC|EBC|transistor_12
Wire||719|462|21||11|#000000|2|11|||
LED|0|775|366|1|LED|LED?|1|||IC||led_11
Wire||746|269|21||11|#FF0000|3|11|||
Resistor|560|750|235|1|Resistor|R?||2||IC||
Wire||827|104|21||11|#FF0000|2|11|||
Wire||288|462|21||11|#000000|2|11|||
Wire||207|462|21||11|#000000|2|11|||
Wire||396|462|21||11|#000000|2|11|||
Wire||261|104|21||11|#FF0000|2|11|||
Wire||234|104|21||11|#FF0000|2|11|||
Wire||425|185|11||11|#FFFF00|5|11|||
Resistor|750000|562|152|1|Resistor|R?||2||IC||
Wire||719|104|21||11|#FF0000|2|11|||
Resistor|240000|643|180|1|Resistor|R?||2||IC||
Wire||827|269|21||11|#FF0000|3|11|||
Wire||775|460|11||11|#FFFF00|3|11|||
Wire||854|104|21||11|#FF0000|2|11|||
Wire||883|185|11||11|#FF0000|2|11|||
Resistor|560|229|272|2|Resistor|R?||2||IC||
Resistor|1000|616|400|1|Resistor|R?||2||IC||
Wire||452|432|11||11|#FFFF00|6|11|||
Wire||695|432|11||11|#FFFF00|2|11|||
Note||839|369|1||||1||To + Spk||NOTEPAD_11
Note||864|424|1||||1||To - Spk.||NOTEPAD_11
Note||719|189|1||||1||250K Pot||NOTEPAD_11
Wire||625|229|21||11|#FF0000|3|11|||
Note||943|506|1||||1||To - Batt||NOTEPAD_11
BREADBOARDSTYLE=BB15
SHOWTHETOPAREA=false
 
Last edited:
Top