Stupid Question #173

[Chris60601]

I feel that I just keep asking questions that I should know the answer but....

Is there any sort of tutorial or trick or something that will allow a simpleton, like myself, to take a Vero layout and convert it to a normal schematic?

I'm not looking for a software package, but the knowledge, know-how and eye to do it on my own.
Sort of like reverse engineering. I'm more than willing to spend the time needed to learn just need some guidance and pointers.

Cheers
Chris

[tabbycat]

everyone starts everything knowing nothing. there's no need for awkwardness about asking questions. we all have once. collective consciousness still a few evolutionary steps away.

in a sentence, the relationship between the two (schematic and vero) is the same relationship as between a topographical map of london and a tubemap of london. the vero is the schematic in essence, just organised in a more convenient form for quick consumption. but all the fundamental components and connections are the same or it wouldn't work.
so, one-click software excluded, i suppose it's like anything, start with a little circuit and build up until you get to the scale you want to work at. there are basic universal schematic conventions that you can follow.

there was a great beavis page about the lpb1 which illustrated the journey from schematic to vero. the journey back is just the same in reverse. all symbols etc here. beavis was great. still around in bits here and there.
http://www.co-bw.com/DIY_Schematic_To_Project.htm

most schematics place the live rail across the top and ground across the bottom, most begin the signal path with the input starting at the right, and work left to the output. the symbols and network conventions for showing wires connecting, and wires crossing but not connecting, are here, along with the classic component symbols. they are standardised.
https://en.wikipedia.org/wiki/Circuit_diagram
it would be damn handy if diylc could covert from one to the other at the touch of a button, but as far as i'm aware there isn't any software that does this yet. that would be a sweet tweek though.

if that sounds at all patronising or beneath your level i didn't mean it to. am not entirely sure what your level is. but when i started out i couldn't see the link, and with practice it came.
the best circuit to practice on is one you really care about (i know the superfuzz schematic better than i will ever know london). that's maybe the most useful bit of advice i can offfer. working with a circuit that you really need-want to understand will take care of the motivation side of learning for you (usually the hardest bit). which just leaves putting in the hours.

it's not as hard to get your head around schematics as you think it is, is another thing i can tell you. it's mercifuly logical once you get past the basics. it's basically flow charts with electricity.

http://www.steveprentice.net/tube/TfLSillyMaps/anagrammap.gif

http://www.steveprentice.net/tube/TfLSillyMaps/rude_map.jpg

[rocket88]

Not a stupid question at all. I've done it on a few occasions, and it's a bear. I do the same thing that I do when reverse engineering a pcb. If you see the top and bottom of the board, put the two on top of each other making the top transparent and just follow the input writing each component and where it connects. Dare I ask what you're trying to do it to, cause I'm sure if there's a vero for something and it's within the community I'm sure there's a schematic laying around.

[Chris60601]

Well said tabby - Not quite what I was after but never the less, I know that your analogies will certainly not fall on deaf ears, so thank you. I did come away from your reply with a confirmation of my initial thoughts on how to proceed.

Rockett - nothing in particular *cough* Maxon OD808 *cough* I do have 2 schems that I did find. But more in reality, I have spent so much time searching for various schems that this site offers on Vero. What I am finding; a good bit of the basic stomps. Now an then I'll run across something a little newer, but for the most part I can't tell you how many Fuzz Tones, Rangemasters, LPB's etc I have run across just looking for a wider variety :)

But taking tabby's words; I suspect that just sitting down with the vero version of the MOD808 will be a start. I guess I just need to start somewhere. I dunno why, but I have been obsessed (and I mean OBSESSED) with the MOD808 after I built the vero from here (both reissue and not).

It's kinda odd really. I dont have an issue with schems and doing PCB's. I always had an issue working with schems to Vero, so its just a mental thing I suppose.

Arrggh - this hobby will be the death of me or the demise of a marriage, lol (I kid, I kid).

[tabbycat]

rocket88 wrote

Dare I ask what you're trying to do it to, cause I'm sure if there's a vero for something and it's within the community I'm sure there's a schematic laying around.

rocket makes a good point. if someone has made a vero for something they made it from something (i.e. a schematic). freestompboxes is your interweb library for stompbox schematics. fsb is (infamously) gutshot and tracing central. definitely worth signing up if you are not there already. free to join with just an email address, and they don't spam you or anything stupid. tons of schematics and things not visible/accessible until you join up.

[Chris60601]

A little off-topic, I never noticed till now - Rocket, yer an administrator here?!?!
Say what?!?!
Werd - if this was recent, congrats!

[tabbycat]

Chris60601 wrote

A little off-topic, I never noticed till now - Rocket, yer an administrator here?!?!
Say what?!?!
Werd - if this was recent, congrats!

i for one welcome out new icbm overlords...

[rocket88]

Lol, thanks man. ICBM overlords? For once I don't get it. Haha. But, I'm not the emperor of the Germanium Deathstar for nothing. Haha.

But seriously, it just happened Sunday, and it's not just me. Mark's going to make an official post about it when he gets back from holiday. So I haven't said anything about it, it's up to the fearless leader to say. Lol

But back to the original topic. When I first started trying to understand I always tried tracing the vero to schematic and drove myself up a wall. I forget if it was mark, miro, or induction that in kinder words then I can remember, seething like "dumbass don't do that it's just going to make your confused like you are, just look at the schematic and trace it on the vero. Once I did that everything really fell into place and now it's not that hard for me to see the circuit on the vero. If that makes any sense....

Also, trust me you're not the only one with an obsession for a certain effect. It happens to us all. Looks at Travis with tonebenders, Javi with big muffs, beaker with any sort of nasty fuzz, for me now it's phasers I can't get enough of them.

[induction]

It seems like a simple progression, right? 1) First you build from pre-existing layouts. 2) Then you create your own layouts from pre-existing schematics. 3) Then you create schematics from pre-existing layouts. It turns out that the step from 2 to 3 is orders of magnitude more difficult than the step from 1 to 2.

The reasons for this are pretty simple:
- Schematics are a language, they are designed around certain graphical conventions to communicate the operation of a circuit. Layouts, on the other hand, are designed to give you something you can build without understanding it. The conventions used in layouts are more about compactness and robustness, and not about communicating the operation of the circuit.

- Reverse-engineering a circuit from a layout (vero or otherwise) usually requires you recognize the subcircuits you find in the layout. You have to spend a lot of time reading schematics and understanding what all the components are doing, and maybe even designing your own circuits so that you can more easily interpret what you see on the layout. Educated guessing is almost always the first step in reverse-engineering. Very often, you start by counting the active components, and then thinking of the circuits you know of that have those components. This gives you a starting place to draw a diagram and start filling in component values. (eg. 'It looks like it might be a variation on a BMP with some component variations and an input buffer.') In other words, the skills and knowledge that are needed for reverse-engineering are the same ones that are needed for designing and modifying circuits.

It is possible to simply follow the connections in the layout, but it gets complicated really fast, and it's easy to lose your place and have to start over. Here's an analogy: Imagine a beginner guitarist trying to figure out how to play Hotel California (or Eruption, Texas Flood, whatever). He has learned some songs, but knows no music theory at all (no scales, no diatonic chord theory, no idea about keys or time signatures). Even with a really good ear, he has no guiding principles on which notes are likely to show up in the song, he simply has to hunt for each note and then memorize. If he knows some theory, he can figure out the key, then take a guess at which chords and scales fit. Now he has reduced the options and fit them into some kind of organizational structure that is specifically designed for the task of understanding music composition. Much, much easier. Much, much faster.

I agree with the advice given in this thread already. Layouts are built from schematics, so if there's a layout, you can probably find the schematic. If there are multiple conflicting schematics for a given circuit, just try them one by one. It is much easier to trace a schematic on a layout and see where it starts to deviate, than to reverse-engineer a layout.

Spend as much time on the breadboard as you can. That's where you really learn about circuits and schematics. That is where you will learn the basics that you will need if you ever do really want to reverse a layout and can't find a schematic. These are the same basics that you will need if you want to design your own circuits, or modify existing ones, which is much more fun than building other people's stuff without understanding how it works, IMO.

If you want to see reverse-engineering in practice, head over to FSB and read one of the threads with '[traced]' in the title. Often these are traced by multiple people working together, looking at photos of the circuit boards. (Usually they trace pedals with pcb's, but tracing a vero layout is not really any different.) There are usually multiple false-starts and bad guesses, followed by a process of refining the topology and then filling in the components. The guesses and refinement are accompanied by analogies to other circuits ('Klon input buffer, followed by two mu-amp stages, then a James tonestack, and a makeup gain stage similar to a Microamp'). You can learn a lot about circuits and about reverse-engineering from those threads.

[Marbles]

Very usefull advice, thanks!

[tabbycat]

rocket88 wrote

Lol, thanks man. ICBM overlords? For once I don't get it. Haha. But, I'm not the emperor of the Germanium Deathstar for nothing. Haha.

intercontinental ballistic missile (icbm) = rocket88. anyone would think you've never protested an american nuke base in the uk. i could tell you a great story about some dear anarcho-feminist friends, a six foot dildo and an american arms base here, but frankly... it would be off topic.

rocket88 wrote

Also, trust me you're not the only one with an obsession for a certain effect. It happens to us all. Looks at Travis with tonebenders, Javi with big muffs, beaker with any sort of nasty fuzz, for me now it's phasers I can't get enough of them.

the obsession creeps up on you like a sickness and constantly mutates. i've still got major shinei-univox fuzz fever, probably terminal, but am also just getting bits together for a vintage clone theory.
either a sick fuzz or a major phaser obsession would be debilitating but ultimately survivable on their own, but if i go head over heels for this clone theory my days will surely be numbered. that's like a cold sore and ebola on the same day.

induction wrote

- Reverse-engineering a circuit from a layout (vero or otherwise) usually requires you recognize the subcircuits you find in the layout. You have to spend a lot of time reading schematics and understanding what all the components are doing, and maybe even designing your own circuits so that you can more easily interpret what you see on the layout. Educated guessing is almost always the first step in reverse-engineering. Very often, you start by counting the active components, and then thinking of the circuits you know of that have those components. This gives you a starting place to draw a diagram and start filling in component values. (eg. 'It looks like it might be a variation on a BMP with some component variations and an input buffer.') In other words, the skills and knowledge that are needed for reverse-engineering are the same ones that are needed for designing and modifying circuits...

If you want to see reverse-engineering in practice, head over to FSB and read one of the threads with '[traced]' in the title. Often these are traced by multiple people working together, looking at photos of the circuit boards. (Usually they trace pedals with pcb's, but tracing a vero layout is not really any different.) There are usually multiple false-starts and bad guesses, followed by a process of refining the topology and then filling in the components. The guesses and refinement are accompanied by analogies to other circuits ('Klon input buffer, followed by two mu-amp stages, then a James tonestack, and a makeup gain stage similar to a Microamp'). You can learn a lot about circuits and about reverse-engineering from those threads.

this bit of induction's post reminded me of something the great RG advised me (in a post over at fsb in fact) about the concept of the 'minimal cut set' in relation to working out how to divide a big circuit layout into smaller sub-circuits (macro/micro). i hope he won't mind me reposting the paragraph here:

There's a concept from design automation that's helpful in understanding, but hard to apply until you have already learned the circuits well enough that cutting it into blocks is second nature.

In PCB automation, there's the idea of a minimal cut set. If you want to separate a circuit into smaller pieces to place them on a PCB, you look for the places in the circuit where you "cut" the fewest wires to separate clots of circuit. Since power and ground (for single power supply circuits) go everwhere, you can ignore them, and just count wires other than power and ground.

A cut set of 0 indicates that the circuits share ONLY power and ground, so they don't interact electronically at all, and can be put anywhere relative to one another. That also is a good indicator of a place to separate circuits into component clusters, as is a cut set of 1. If two circuits interact through only one wire, they are probably either first/second, or parallel circuits. In either case, that's a good place to cut.

A cut set of two is probably either a differential first/second setup or a first/second with a common bias. More than two is "hey, isn't there some place else to cut this?".

i was just getting to grips with the superfuzz schematic at the time (despite having already built a perfectly functioning one from a vero layout a few years earlier) and though i'd sketched out a few rough ideas i had picked up about identifying clipping diodes, tone scoop, the octave pair, as soon as i followed RGs hint and traced through it looking for the fewest cuts, the circuit fell apart like a ripe orange, neat little segments, all tidily separated by 10uf caps. it was quite a satisfying moment. empowering etc.

with mainly RGs hint and some stuff i found at kitrae's big muff page http://www.kitrae.net/music/big_muff_guts.html  i was able to deconstruct the superfuzz and attempt the dissection of a ton of circuits since using the same basic tools.

so am passing it on in the hope it will be useful to someone else here.

[rocket88]

Bwahaha. Tabby. Bro, you're too much some times.

[motterpaul]

It is funny - because I just built the "original"  maxon OD808 from this site, but there also seems to be a re-issue version. The main 808 they show here features 2 4558 chips, while the most common schematic I found only has one IC but adds two FET 5457s as the other gain stage (which is the reissue).

I never did find a schematic for the 2 IC OD808 shown here in vero, so I am not sure where it came from. But the reissue schematic comes up quickly.

Sometimes on a vero I find myself just printing it out and drawing arrows to try to trace the signal flow.

To find a schematic online I usually just use the name of the pedal in Google, +"schematic" and then click on "images."

But I realize that is not the original question. Like anything, I guess the first option you have to create an original schematic from a vero is to "draw it" until you get it. There are some programs online (Fritzing, LTD) though, that try to take PCBs and/or schematics, and make one from the other - but the results are often pretty confusing (just a start, actually)...