Urgent Help Please Circuit Design 555 Cd4017

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CORRECTION

Put a 100R or near resistor in series with the meter leads and switch the meter to 100mA DC and measure the current at pin 7 of the 555. The other meter lead connects to the 0V line
 
ok kool that may have been my fault im not sure if i did that when testing or something. so how do i test there is no short?
 
UPDATE

200m, bottom left. The reading should be zero to about 3; very low!
 
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i only have a 200r resistor, trying that i came with the following
i wasnt sure if i needed to do it powered up or not so i did both
unplugged 0
plugged in 31.7
 
OK. There is a short between pin 7 of the 555 and the 6V supply line.

Remove pin 7 of the 555 from the circuit and do the same measurement, either at the bottom of the 2K7 pull-up resistor, or pin 14 of the 4017. The meter should read between zero and around 3
 
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That is an OK reading. Now connect a wire between pin 3 of the 555 and pin 14 of the 4017 or bottom of the 2K7 pull up.

Set the meter to 20 (top right). You should see a voltage swinging between 0V and 6V at pin 14 of the 4017.

(Best keep checking in case I update my posts)

UPDATE
Pin 7 of the 555 should not be connected to the circuit again. That output is blown.
 
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ok i think i got something more wrong with that chip (i do have another though from the first circuit as i bought a new one today for this one)

i did a reading with pin 3 (555) attached to pin 14 (4017) reading fluctuated between 3.2 and 3.4

i removed it again and tested pin 14 on the 4017 and the it read 6.4 (nothing connected other than the resistor to pin 14)

i then tested the 555 pin 3 without pin 14 attached and the reading is the same as when connected to pin 14
 
That does not make sense- the circuit not you. Are you sure you measured on pin 3? It sounds like pin 4.

UPDATE

You have removed the 200R resistor and switched the meter to 20V
 
definitely measured on pin 3 ill try and draw up a quick circuit of the other board and maybe you could see if its close and what changes i need to make? if you dont mind. it will only be in paint tho.
maybe i did something with a chip on this board

edit: actually i will redo the board and get back to you thanks
 
Keshin, stay with this board for the time being. We will soon get to the problem. Don't keep thinking you have made a mistake.

Are you sure you switched the meter to 20V (top right in your picture)
 
Good move. hope you didn't mind me checking.

This is how I see it. The present 555 is toast.

Can you fit a new one, but leave pin 7 disconnected.

Connect the negative lead of the meter to the 0V supply line. Switch the meter to 20V and check that pin 3 of the 555 is swinging between 0V and 6V.

Don't rush. Take your time. Have a beer or a coffee.

Let me know how it goes

spec

(PS: weather you have made a mistake or not is not relevant- I make mistakes all the time, and I have a mountain of blown components, especially loudspeakers to prove it. The only way to avoid mistakes is to avoid doing anything )
 
haha thanks ok i will switch out the 555, leave pin 7 disconnected and test, but first its definetly time for a coffee. should have it done in about 30 mins
 
Good move

Don't worry about me. I have more than enough things to do. Your posts are no inconvienience whatever!
 
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