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Need Help Figuring Out the Schematics Of Circuit Board

Circulon

New Member
Hello Everyone !! im a newbie here , just joined like an hour ago, Im a Hobbyist , have very very very minimal knowledge in electronix, just know enough, to know "where not to stick my fingers on a live circuit board" lol :).

So people !! here is my humble query, I have the " image" of a circuit board with all its components installed in it .. ...BUT its like looking at the image of Turtle from the top, there no way (at least for me ) to know whats Beneath the turtle ( cause- its just an image ) .
That circuit is from a toy from the 80's - which apparently has flashing lights - the toy is not being made anymore, the company itself is not there anymore. I take it as a challenge, upon myself to rebuild this toy from scratch. But i don't have the knowledge to figure the circuit in this way, also it involves 2 IC's. The Black Wires get hooked up to tiny bulbs ( i dont know what voltage those bulbs will be ??), and this toy was powered by 3 size "D" batteries so thats like 4.5volts ??

Oooop i had to get back in and edit my post ... as i realized that maybe the image cant be enlarged ???or not?...well the part # for the two IC's are as follows :

my conversation with my buddy , chatGPT
Question = hi !! - this M4017 ic and the M4011, both are used in a toy circuit with switching lights that go on and off when a ball hits it ? can you elaborate more on that ?
Answer = both ic’s as obsolete not being made any more the alternative to use is CD4017 and CD4011 respectively …and ….

The IC Roles in the Toy Circuit
M4011 – Quad 2-Input NAND Gate
This chip likely handles:
1. Signal Conditioning
When a ball hits a sensor (button, piezo, reed switch, etc.), the signal might be noisy or bouncy.
The M4011 is probably cleaning this signal (debouncing) before it’s sent as a clean clock pulse to the M4017.
2. Logic Control
It could be gating signals (e.g., allowing counting only under certain conditions).
It might also combine multiple inputs (like "ball hit" AND "game on") to allow LED advancement.
In short: M4011 processes and filters the "ball hit" signal.
----------------------------------------------------------------------------------------------------
M4017 – Decade Counter
This chip is doing the main LED sequencing:
1. LED Chaser Behavior
Each valid pulse from the M4011 advances the active output pin on the M4017.
Those output pins (Q0–Q9) drive LEDs — lighting up a different LED after each hit.
2. Looping Back
After the 10th LED, it loops back to the first, restarting the sequence.
In short: M4017 counts clean hit signals and lights up the next LED in order.


Can someone help me figure out the schematics of this circuit ?, what it would look like ? and what components / with values would I need to buy ??
Any Help, Advice and or Guidance, Much Appreciated , Please and Thank you !!

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Guess:

Two gates form an oscillator that goes directly to the 4017 Clock input.

Two gates form a true monostable with a pulse period equal to 30 clock pulses from the oscillator. The monostable drives the 4017 ClockEnable- input. The monostable period is so long (over 1 second) that switch debouncing is not necessary.

ak
 
The videos show very different light patterns with no explanations. Which part of which video is the effect you want to achieve?

ak
 
It's a single-sided PCB. Reverse engineering it should be super easy.

Post a photo of the back side of the circuitboard.
 
It's a single-sided PCB. Reverse engineering it should be super easy.

Post a photo of the back side of the circuitboard.
unfortunately i dont have the board, and hence i came seeking help here, i only have the images and the vid to work from . This thing is obsolete from the 80's, but i love bringing Frankenstine back from the Dead :)
i figured out the IC, ...BUT if someone can help figure out what the transistors are ? what part nr. or value ? also if someone can help figure out whats the CERAMIC CAPICTOR part nr. or values are . As there 4 ceramic caps in this circuit , and then there are 2 electrolytic caps - of which one of them electrolytic caps is 4.7uf or 47uf ??? and guessing 16v to 25v ..the resistor as far as i can see with My Four-eyes ,,,they either are colored yello-purp-orng - 47ohms...or yello-purp-brow 470ohms with a black band of +-20% tolerance ( im not sure ) and guess its 1/4watts by the size (also not sure)...
Also people i see something intriguing (maybe to the untrained eye like me) what is that WHITE COMPONENT ???? what is that ??? between the two IC's to left of disc capacitor#2...is that a diode ? i thought all diodes are Black with silver bands ????
 
The videos show very different light patterns with no explanations. Which part of which video is the effect you want to achieve?

ak
since there is no Pot. in this circuit so im assuming theres no speed-controll for the flashing of the lights...and hence ...(maybe ) .... the "patterns" and "speed" maybe auto-generated by the IC ( just a stupid guess) ...and i not bothered about the sequential effects or the pattern of the lights ( like whatever the circuit throws at me im fine with that) SO LONG AS IT FLASHES each time the steel ball rides over the trigger Plate and triggers the circuit to do its thing....
thank you for asking - much appreciated !!!
 
"Looks like a 4011 IC (4 two-input NAND Gates) used to make an RC oscillator which then drives the 4017 IC which is a johnson counter. Each counter output drives the base of a BJT. The BJTs act as buffers because the outputs cannot drive incandescent bulbs directly."
you are Absolutely right !! i looked up definitions on 4011 = quad 2 input nand gate...and the 4017 =decade counter w/10 outputs., but am not educated into electronics - not even 0.10% , so most of the stuff (technicalities) just bounces right off my head...
But the more i look at this circuit - i instinctively feel and know its "easy" / "doable" ..its got like just 30 components to it....
All or any input / advice from you guys here is ENLIGHTENING !!! mean it, n much appreciated !!1
 
Which version of the game do you have. Wikipedia lists them - do you have the same one as in the video ("set L")?
 
Presumably it's just a 9 way 'chaser', with the small bulbs lighting one after the other - here's an example of a similar kit - and there are countless others on Ebay etc.


If you wanted bulbs instead of LED's (why would you?), then add a simple driver instead of the LED's:

 
The white axial part is a jumper. In a circuit and pc board design where there are very few trace crossovers, a few jumpers are cheaper than going to a double-sided board - especially back in the 80's.

yellow-purple-orange is 47K, not 47.

ak
 
you are Absolutely right !! i looked up definitions on 4011 = quad 2 input nand gate...and the 4017 =decade counter w/10 outputs., but am not educated into electronics - not even 0.10% , so most of the stuff (technicalities) just bounces right off my head...
But the more i look at this circuit - i instinctively feel and know its "easy" / "doable" ..its got like just 30 components to it....
All or any input / advice from you guys here is ENLIGHTENING !!! mean it, n much appreciated !!1
Circulon do you want to replicate the same circuit as it is exactly, or are you fine with a similar circuit that does the same thing? The circuit you've got is commonly called an "LED Chaser". There are many schematics online similar to the circuit in your pictures, like this: https://www.eleccircuit.com/led-chaser-circuit/

It would take a while to figure out exactly how they wired everything up in your pictures without actually seeing the traces on the underside of the board and I doubt anyone here would be willing to try to reverse-engineer the circuit and post a full schematic for you, so I would recommend looking up an led chaser circuit online and just building that.
 
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Presumably it's just a 9 way 'chaser', with the small bulbs lighting one after the other - here's an example of a similar kit - and there are countless others on Ebay etc.


If you wanted bulbs instead of LED's (why would you?), then add a simple driver instead of the LED's:

Hi Nigel !! thanks for your response - thks for the circuit on the "simple driver for the bulbs " much appreciated !! - that explains part of my circuit , (the resistor, transistors, and the Bulbs)....

Also the reason why i want to stick with incand.bulbs is because the illumination is visible from any angle n distance - as OPPOSED to led's, led's illumination , in a heavy-lighted area - is/are visible only from the TOP and and at certain angles - otherwise - (look like they're dead) - Also this toy is "Ancient" - so i want to stick with its originality (as that's where its beauty comes in - for me at least )
 
Presumably it's just a 9 way 'chaser', with the small bulbs lighting one after the other - here's an example of a similar kit - and there are countless others on Ebay etc.
hello Nigel !!! thanks a lot for the link to the kit - i didn't realise the "mitch" link ... i was, instead, clicking on the "winpicprog.uk" link and was getting no where...just noticed the actual link today.
Its so close to what i want - temptingly close - difference is (uses the Ne555) .... i would have bough the kit in a flash , BUT unfortunately ...... the shipping cost Uk to Can. is Prohibitive AF ...Plus taxes and duties.
Still, But thanks for the Link !!!, i was reading up the explanation of the 4017 light chaser circuit they put up there, makes things easier to understand for a beginner.
 
Circulon do you want to replicate the same circuit as it is exactly, or are you fine with a similar circuit that does the same thing? The circuit you've got is commonly called an "LED Chaser". There are many schematics online similar to the circuit in your pictures, like this: https://www.eleccircuit.com/led-chaser-circuit/

It would take a while to figure out exactly how they wired everything up in your pictures without actually seeing the traces on the underside of the board and I doubt anyone here would be willing to try to reverse-engineer the circuit and post a full schematic for you, so I would recommend looking up an led chaser circuit online and just building that.
hello Glasgow !!! Thank you for the link !!!!! the guy has the circuit that uses both the 4011 and 4017.... maybe it worth a try - BUT how do i figure out how to join it all on a breadboard ? :(
Nonetheless , but Thanks a lot !!!!
 
I WOULD LIKE TO THANK EVERYONE THAT REPLIED TO MY QUERY , AND THE VALUABLE INPUT, GUIDANCE AND ADVICE THAT ALL YOU GUYS GAVE ME , MUCH APPRECIATED !!!

Well at least now i know its a light-chaser circuit, so its not so intimidating, as i thought it would be something complicated since it came from the 80's and went Obsolete - and hence wanted to stick as-close to the original. Also its a good thing that this was not reverse engineered - as i now realise theres better stuff (circuits) out there.

thank you everyone !!!
 
hello Nigel !!! thanks a lot for the link to the kit - i didn't realise the "mitch" link ... i was, instead, clicking on the "winpicprog.uk" link and was getting no where...just noticed the actual link today.
Its so close to what i want - temptingly close - difference is (uses the Ne555) .... i would have bough the kit in a flash , BUT unfortunately ...... the shipping cost Uk to Can. is Prohibitive AF ...Plus taxes and duties.
Still, But thanks for the Link !!!, i was reading up the explanation of the 4017 light chaser circuit they put up there, makes things easier to understand for a beginner.

There are countless similar kits out there, plenty from the USA, but mostly from China with cheap postage - just google for them, or look on AliExpress.
 
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