Relay Computer ep. 3 - Completing the 16-bit adder

[@antonnym214]

You should be a professor. I understand you better than anyone else who has explained this stuff. Outstanding work, both technically, and in your communications skills.

[@CNLohr]

When I was a kid, I DREAMED of making a relay computer. When I got older, it lost it's lustre. I am so thankful for people like you so I can live vicariously.

[@goodmaro]

I had exactly the same (day)dream ~50 years ago. But my architecture would've been a lot clunkier. Like, feh, who needs binary? I just imagined 10 wires north-south, 10 wires east-west, and 100 outputs from the pairs of them! Actually just 81 because the 0 would just be an absence -- which wouldn't fail very safely!

[@goodmaro]

If I'm understanding correctly, the ripple nature of your adder makes the time for completion of the operation variable, depending on the number of carriages the data dictate. Which means to pass the output wherever it's going, you need either a "wait" signal (which would need be a multiple-or of the carry bits -- just a "short" as you call it) or to clock it to the maximum required, making the overall architecture synchronous.

[@AppliedCryogenics]

I just started this series, and I'm excited to see how it turns out. I'm suspecting a potential problem with the fact that signal lines in this system have to be able to drive sometimes multiple relays, together with the narrowness of these traces and their traversal over 0.1" header pins, there may be some hot spots with increased fanout. Of course this all happened 7 years ago, so I'll soon find out if I am totally wrong or not. Geek on!

[@TheYaronn]

I really enjoyed watching the video series! I liked the in-depth explaination of both the theory and the construction. Can't wait to see future episodes!!

[@haakonpad]

The computer's coming along nicely i see. This is going to be so cool when it's finished :D Can't wait for the next episode!

[@ClicketyClack]

Thanks - I should be able to do some new episodes in a more timely fashion now. Glad you're enjoying the project.

[@antonnym214]

Great video with nice production values. Content and context excellent. Everything is well-explained and shown on camera. Very interesting stuff. You are helping me with my research. I'm considering making a RISC cpu. Very small instruction set and memory to keep the number of relays low.

[@josedominguez2021]

Thaks man, Hiper VDO. I love relays.

[@robynwyrick]

This is totally addicting.

[@DSUSN127]

I feel like an idiot. I literally just realized why your voice sounds so familiar. Hahaha. Cool video series. Hope to see you again soon.

[@ClicketyClack]

Ha! Thanks Daniel!

[@drewduncan5774]

Any chance you'd ever construct a relay circuit for floating-point arithmetic?

[@ClicketyClack]

I'm not planning on it - floating point is pretty complicated to do.

[@drewduncan5774]

True... but it would be really cool.

[@Tristoo]

you don't need relays to do a shift, and floating point doesn't just require adds

[@Mrpilka987]

this have so much potential, it's going to be amazing.

[@josedominguez2021]

It is not possible, you have only three vdos. We want more!!!! Please. I love Relays.

[@frac]

Fantastic. MOAR! MOAR NOW! Sleep is forbidden! Honestly though, great videos. Really looking forward to the next bits (Heh. See what I did there?).

[@Ezra_TheKing]

lol bits HAHAHAHAHAHA

[@Ezra_TheKing]

And yes the video's are pretty proffesional unlike my spelling lol

[@Blacklab412294]

I think you did a great Job. Did you ever reworked the board, so you didn't have to use Jumpers to fix things? Also would it have been helpful to add a LED & Resistor across the coil so you could see which relay was on ?

[@jacobcorr337]

Are your schematics available anywhere? Great vids! Excited for the remainder of the project.

[@thefish5585]

Can you provide schematics for this whole project.

[@matata66]

Question, at this point, can you give just one input at once, or are there multiple inputs ate te same time ?, ( i am learning )

[@WellingtonAlbuquerque]

What is the orange thing called U1 and U2?

[@ClicketyClack]

Those are resistor networks - basically eight 330Ohm resistors in one package with one common pin.

[@WellingtonAlbuquerque]

Thanks. Nice job

[@Mckooldude]

Are the Gerber files posted somewhere? I'm definitely interested in spinning up some boards.

[@tahwnikcufos]

Oops... a little light on pin 9 of U1 5:30 ;-)

[@iMacGeekDK]

Awesome project. Really sparked my interest in digital electronic enigneering. I want to bulld a 4 bit computer, can you recommend any book on CPU architecture? :) Greetings from Denmark

[@ClicketyClack]

Thanks! This was partly inspired by the (short and easy) book CODE by Charles Petzold. It describes a hypothetical relay computer to explain digital logic. It's just beginner level, but surprisingly thorough and has wonderful diagrams. :)

[@edgeeffect]

Very well produced video (KZbin electronics needs more of this sort of thing) maybe the pace is a bit on the slow side (but maybe I'm just too impatient)... and a great project... relay computers are the most aesthetically pleasing... are you sure that's a "no" for the nixie tubes?

[@samba3403]

is this still moving forward?

[@ct6502c]

Very interesting! But all those relays must have cost a small fortune!

[@chiefartificer7159]

Fantastic work! Please don't forget to provide the PCB files as you produce them! Github could be a good choice. And if you ever write a book about the subject count me in as a customer. Thanks in advance!

[@gorillaau]

chief artificer I'd buy a copy, even if I don't intend building one. These are what we may have had today if the silicon wafer didn't come along.

[@TomStorey96]

liking your videos! try using blu tack to hold your parts in place while you solder them in, instead of bending leads. just remember to remove the blu tack before you solder any leads that are close or in contact with the blu tack as it can leave a bit of sticky mess behind.

[@pypy05]

But can it run crysis?

[@grimtin10]

dammit

[@jhallenworld]

Wow nice video! But hey man what are you doing? I've also made a relay computer ("single board relay computer") and you are forcing me to raise the production values of my own videos...

[@davidprock904]

Piece of shelving, sheeeet... use the walls of your house

[@gravypod]

Where do you hide your time machine back to the 70s? I can't imagine another way to get this many relays.

[@Zenas521]

You make high quality videos and would like to see the nest video... Hello?

[@Wingnut353]

Most of these relay computers implement a bus interface.... rather than implement large custom boards to test the individual subsystems... why not just go ahead and implement the bus interface and test from that level.

[@mydix2small859]

Judging by your Hands, you have an Underdeveloped veinous system, you need to Exercise More.