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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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Last edited:
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.

To make a similar circuit, first find out how to make an oscillator using NAND gates. Alternatively, if you do not care whether your circuit is built in an indentical manner to the one in your image as long as it works the same, you can use a different clock source like a 555 timer.
After that, find out how the 4017 IC works (read the datasheet and see what each input should be connected to to make it count) and how to hook up your clock source to it.
Finally, look up NPN BJT switches and how to calculate the required base resistance for them. You can then hook up whatever lamps you want to the output. I'd personally go for LEDs not incandescents but miniature low voltage incandescent lamps are not difficult to acquire online if you want them. You have the option of a supply voltage from 3-18v if you use CD4011Bs and CD4017Bs for your circuit. Choose a voltage that works well with whatever lamps you can acquire. Also if you use LEDs you would not need giant D cells because the current draw would be reduced significantly.
 
wow, Thank you so much for your reply , much appreciated, im not a full fledged , trained electronix person, just a tinkerer - a hobbyist and just some basics, hence the REQUEST for help :) ...
ok so the IC's are figured out, youre inline with what chatgpt said, but what about the Transistors, the resistors, the 2 electrolytic capacitors, theres also a ceramic disc cap, and then a polyester cap (if im not mistaken) , also theres that "white component" ( i dont know what it is) -
How do i figure out ALL the values and part numbers for these ? and even if did , how do i figure how its all put together _ (im not at that stage as yet - not even close)
But nonetheless, Thank you !!
 
I suspect the 4011 acts as a debounce and monostable, producing one "clean" pulse each time the switch is triggered.

Is is supposed to advance by one with each hit? Or, do all the lights sequence around after each hit?


The 4017 part is straightforward, that IC just steps along it's outputs each time the clock input is pulsed.

There is also probably a power-on reset so it always starts up in a defined state when switched on.

I'd use a 4093 rather than a 4011 (same gates though with schmitt trigger inputs), but a functionally similar circuit is simple enough to create, whichever way it is supposed to work.
 
The transistor circuit, given its driving filament miniature bulbs, probably looks like :

1746906692682.png


The load is the bulb, the Rb to limit base current to max allowed for 4017 current out and transistor base
allowed max. Vbb and button not used, connection to Rb from 4017 output.

Why dont you remove board from standoffs and just manually trace/draw the schematic ?
 

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