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Relay Logic

I have a fetish for antiquated technology. Stuff like vacuum tubes, transistors, electro mechanical devices, and of course relays used to run things. I did a few searches here on Instructables on relay logic and found nothing so I thought I'd start a forum on it.  Most of the earliest computers ran using relays. I love how they sound, clickity - clack. In a way they seem more alive to me than todays silent electronics, and dead boxes, There's just something cool about a machine that you can hear working instead of dead silence, maybe I'm just a old fashioned.  Anyway, I have a limited knowledge using relays for adders, if, and, or, gates, etc. but I'd like to learn more. I did however make a clock circuit using only relays and capacitors, and I have a video of it here... http://www.youtube.com/watch?v=Ya5R7EqF8vk I based that circuit (after lots of pondering and experimentation) on the clock in this relay computer here. http://www.youtube.com/watch?v=n3wPBcmSb2U My relay clock was really unstable and would stop by itself quite a bit. I'd like to figure out how to make it more stable. Also, I'd like to do some more experiments... Anybody else have any interest in this subject? Or have any experience making small bit relay computers, or relay control systems for robots, etc? By the way here's some other cool relay run computers and stuff. Another Relay computer http://www.youtube.com/watch?v=O-omFP_G57U&feature;=related Relay counter thing. http://www.youtube.com/watch?v=YQ4ynGxQnGY Mechanical pong game - run on relays http://cyberniklas.de/pongmechanik/indexen.html

Topic by bart245    |  last reply


Problem with the HEF4008BP IC chip ??

I just bought a HEF4008BP 4 bit binary adder ic. I connected pin 16 to V+ and pin 8 and 9(Carry in pin ) to ground  and then set up a 8 way DIL switch with 10k and 1k pull down resistors to gnd and the switch  to the inputs of the adder.Then i connected the outputs of the adder to the positive of a 3mm led each separately  .The dil switches are all of but still all the led's light up once i connect the 9v battery . The chip can run off 5v-15v . Also there is no sign, name or logo of a manufacturer on the ic .Is this a fake ic or might i have possibly blown it or have i done something wrong .Please help me.

Question by Strontium    |  last reply


Is there windows program that makes apps for the iPhone 3 and 4?

Hi, i'm running a Windows Vista service pack 2 PC and i'd like to develop apps for the iPhone and the programs interface is close to the same function as Game Maker, Visual Studio and Dreamweaver MX 2002, it has got four modes that are avalible and it MUST let me select 1 of them every time i start the software and it should be a lite or beta of the software so that i can have it forever and buy it if i like it and i'd like to have these requirements: Normal app maker mode: able to build advanced software has all the formatting of Visual Studio Panels for inserting objects Buttons Web Browser formatting (web pages are viewed inside this) Comment box adder Title box adder Radio Buttons CheckBoxes  

Question by shoyru_master_11    |  last reply


Problems with the 4511b IC chip??

SO i made a circuit which is a binary adder(using the 4008b) that adds numbers in binary and then passes on the result to a 4511 IC(its a BCD to 7 segment decoder),so basically it adds numbers in binary and displays them in decimal .It seemed to work fine for a while but then suddenly when i tried adding 0011 +0001(3+1) in binary ,it still displayed 0 and then i tried tapping the battery for a second or two and then suddenly the seven segment display shows 4 .The circuitry is all fine and right .but do i have to connect latch enable(pin 5) pin of the Ic?.Both the IC's run on a 9v battery and for the 4511 decoder IC i used 33k pull down resistor .Is my pull down resistor value for the 4511 IC too high ?The binary adder part seems to work very well,its the bcd to 7 segment decoder IC part that I'm very much concerned about.Is there too less power for both the chips to run on?I've not got a single idea at all .so, >PLS help me if you can.

Question by Strontium    |  last reply


Diode Calculator will not work

I've been working on a diode only (well, plus switches for input [numbers, yet there's only one pad! not one for each digit], resistors for various things, and LEDs for the display) calculator that could add two two digit numbers (xx+xx=xxx) for a while, putting countless hours into it.I have deemed it impossible.There's so many problems with a mass diode resistor network that is just won't work. As some and gates conduct then some other gate (like it's suppose to) conducts, and eventually causes a voltage divder (with the pull up/ pull down resistors) and the output gets wacky and there's no wway of amplifying the signal.The diode adder is dead

Topic by guyfrom7up    |  last reply


Learning Redstone

I'm here today to teach you how to have fun with Redstone, now if you don't, you may just jump into a Minecraft sand well and drown. Okay, first thing is first, the BASICS. You may already know that there are what we call 'Logic Gates' in all forms of machines from a computer to a simple on and off switch. We are going to be talking about the main logic gates for now. So let's get started. The NOT Gate: The NOT Gate is what I think is the easiest logic gate to comprehend in Minecraft. It is basically an inverter. It inverts the input. For example, if I were to take an input of Redstone that is on, it would invert it and give an output of Redstone that is off.If it were off, it would be an output of on. This is one of the most used Redstone logic gates. The OR Gate: The OR Gate is also VERY simple to understand, and is also called a Universal Logic Gate, this is because you can use this gate to make any other gate existent. OR basically means 'One input OR the other input  OR both will give us an output'. This is like saying 'Jeff's dog will get a treat if he jumps in the air OR he rolls over, OR does both'. This is also easy to comprehend. (The NOR Gate is the same as the OR Gate except its output is inverted) The AND Gate: The AND Gate reciprocates the OR gate except for one major difference. Instead of 'If one OR the other is on the output is on', it is 'If one AND the other are on the output is on, otherwise it is off'. So what this is saying is that you need to have BOTH inputs on in order to have the output on. This is like saying 'Jeff needs to turn the handle AND push the door to open it'. (The NAND Gate is the same as an AND Gate except its output is inverted, the NAND Gate is also a universal gate) The XOR Gate: The XOR Gate is also very similar to the OR gate but instead of 'One or the other or both', it is 'One or the other'. XOR means 'Exclusive OR', meaning only one of the inputs can be on or else I wont turn on. This is very important when dealing with Redstone calculators or ALUs. It is one of the main functions of a Redstone Adder or Subtractor. (The XNOR Gate is the same as an XOR Gate but its output is inverted) Those are all of the main basic logic gates I'm going to take you through today! These ones are the most important ones to be used and can help people a lot. There are PLENTY more to go through but that would be a bit much documentation for me to handle. If you need any help or need some easy visuals, you can go to StephennJF's YouTube page, or you can also go to bennyscube's YouTube page for help too.

Topic by knexpert1700    |  last reply