With just one double relay, you can make an adder capable of performing 1bit additions:
0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 0 ( with Carry = 1 )
The circuit design isn’t mine, I found it with a quick google search.
This is the complete schematic of the above circuit.
i don’t understand
that schematic is not clear to me i have a short of seven years of studying electronics as an hobby and i can’t get what is drawn
That is a double relay, A and B are inputs ( and as it is shown in the truth table, A and B can only have two values, “1” (V+) or “0” (GND), this is done by switches ), SUM and CARRY are outputs, therefore connected to some indicators ( light bulbs, LED, voltmeters, etc).
V+ is the operating voltage of the relay used.
I wonder if you could make a detailed schematics for your design , I have been trying to make my own copy but I could not manage to work B input , except that all functions are working.
what about full adder?
https://www.antimath.info/electro/4-bit-relay-computer/
Thanks, good work. Just a question:
1) surely the resistor needs to be before the LED?
Yes. It’s a mistake in the schematic.
My second question is: Can you use two of these (with the carry from the first adder being the input to the second) to make a full adder? I don’t have the where-with-all to draw it out, as my head is hurting enough trying to figure out your drawing as it is… Any chance you can draw it out to make a full adder with just two SY4008 relays as you have in the original half adder… Thanks, M
PS: in your drawing, it is a little confusing if wires cross it is not clear if they are ‘jumping over’ or ‘joined’… Thanks, M
Here you can find a block diagram showing how to connect multiple adders.
https://www.antimath.info/electro/4-bit-relay-computer/
Sorry, indeed the schematic is not the prettiest.
It was drawn a very long time ago, and somewhat in a hurry if I remember correctly. If there is a dot where the lines meet, it means there is an electrical connection, if not there is no connection.