Olympic rapid fire training aid

Thread Starter

MarkAB

Joined Feb 27, 2016
80
Hello,

When you used 1M resistors on the position of the 1M pots, the time will be maximum.
It probably still will work, but slower as expected.

Bertus
Thank Bertus.

Ok got the red working now and some approx timings. just can,t get the green to work now!
 

bertus

Joined Apr 5, 2008
20,326
Hello,

Do you use schematic 3B?



When the green does not work, there must be an issue with the triggering from Q2 to Q3.

Bertus
 

bertus

Joined Apr 5, 2008
20,326
Hello,

When the green led does not work, Q3-pin3 does not go high.
Q3 gets triggered by Q2-pin3.
Does the led on Q2-pin3 change state?

Bertus
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
When I close the switch, Q1 and red led's come on for 11sec, then Q1 goes off and Q2 comes on for another 100sec, then both Q2 and red turn off but no green ):
 

bertus

Joined Apr 5, 2008
20,326
Hello,

The 555 should trigger on a negative going pulse.
Do R8 and R11 have the same value?
(there are no values given).

Bertus
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
Hello,

When the green led does not work, Q3-pin3 does not go high.
Q3 gets triggered by Q2-pin3.
Does the led on Q2-pin3 change state?

Bertus
Yes when the green led does not work, Q3-pin 3 does not go high.
Q2-pin 3 goes low at the end of second timming together with the red light and the led on Q2 -pin 3 goes off too
 

bertus

Joined Apr 5, 2008
20,326
Hello,

What happens when you short Pin1 and Pin2 of Q3 for a short moment?

Check the connections of C7 and R11.
Those components should trigger Q3.

Bertus
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
Hello,

What happens when you short Pin1 and Pin2 of Q3 for a short moment?

Check the connections of C7 and R11.
Those components should trigger Q3.

Bertus
Shorting Pin 1 and 2 of Q3 had no effect tried a few times and got the timer started again ???

Changed C7 and R11 and even the whole Q3- 555 timer but still no green
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
hooray did it
Had left the supply of Q3 pin 8 out !
sorry for the stupidity Bertus and thanks for your help
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
And thank you for you plan Bernard it works.
Just need the pots and fine tune it now.
Oh and the beeps should be the next hurdle.
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
Done and it works great. Just one thing how can I make it go back to the red led after the last green?
I would like it to run in a constant loop.
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
It is a bit of a mess on a bread board as it sometimes stops working so it must have a loose connection somewhere.

Here you can see it working great but not looping so will work on it a little more


Do you know of any good software to print a PCB from ?
 

Thread Starter

MarkAB

Joined Feb 27, 2016
80
The repeat function should already be in place. On 3C check connections from Q3-3, C2, R6,,& D2.
Sorry Bernard tried this 100 times and changed all loose wires to rigid ones and now works a treat but still no repeat function :(

I have noticed that pin Q3-pin 3 goes live(+) for green light and then becomes ground(-) to signal restart.

So i have connected the cable (C2 to Q3-pin 3) to live(+) and then negative(-) and it restarts. but when I put it back on Q-3-pin 3 it does not perform the restart ???

Please help
 

Bernard

Joined Aug 7, 2008
5,397
My feeling is that Q3-3 on reset is not going to hard ground. To test you could lift Green LED & R to +6, cathode to Q3-3. Green should then always be on except for last 4 sec.
If Green does not come on, replace Q3.
 
My feeling is that Q3-3 on reset is not going to hard ground. To test you could lift Green LED & R to +6, cathode to Q3-3. Green should then always be on except for last 4 sec.
If Green does not come on, replace Q3.
Done this and works as you said. It even resets back to red, and starts all over. But when I reconnect as normal, nothing
 
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