Boss electronic bypass switch PCB design: I made it! Here it is...

[Morocotopo]

Hi, as promised in my last posts, I designed a PCB for the boss electronic bypass switch for this circuit:

EDIT: now the schem has the parts numbered...
It ended about 7 x 4 cm, kind of large, but with my limited experience I could´t make it smaller.
NOT TESTED YET. Next I´ll etch, build, and confirm if it works or not. I hope the circuit is correct...
I don´t have the slightest idea about PCB design, I just worked from a "lay the parts and connect them in the smallest possible space" point of view, so, no concern about ground planes, 9V crossing signal paths, etc.
I used a perfboard hole spacing as a component spacing starting point, so if it works maybe the whole thing could be made a bit smaller...
Feel free to comment, point errors, improve, prototype, download, copy, distribute, use as wallpaper, whatever.
Hope it is of some use to anybody, my little (hopefully useful) contribution to this forum and its generous people.

[Morocotopo]

Holy !"·$%!!! the images are huge!!!!
err... just download them to see them better...
sorry, I´m not sure how to make them smaller...

[Morocotopo]

Here´s the PCB with cm. scale for printing...

[JimRayden]

This surely wins my "Most Pointless Project of the Year" award. (no offence)

Ever considered this alternative?:



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Jimbo

[Morocotopo]

Some people might find this useful, Jim.
In some countrys, like mine (Argentina) it´s not possible to buy 3PDT´s.

[Morocotopo]

Or 2PDT´s, for that matter.

[spudulike]

You are posting on an internet message board, and 3PDTs are sold on that same board by mail order.
Smallbear ships to South America as do others.
I dont see the problem.

[JimRayden]

Well, I don't see this turning out any cheaper than ordering from Aron, and to my knowledge, he does ship there.

Hmm, any reason for choosing the Boss bypass? Why not the tubescreamer? At first glance it looks far simpler.

Here's an idea - maybe you can mod the layout to fit the switch as well, so you can build a pile of these neat switcher-units for future use in projects. Make sure to wrap them into heat-shrink too. Or were you planning to put them on the same board as the projects?

Anyway, great work on the layout, I might even try it out when I run out of switches.

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Jimbo

[Morocotopo]

Yes, I know aron and smallbear, but ordering them abroad, with customs and shipping,  is about U$S 15-20 per switch or thereabouts, that´s 50 argentinian $, for that money I can make a few switches here.
Also, the hassle of ordering, waiting, I´ve had problems with shipments not arriving before...oh, the horror...
Seriously, I plan to try some 3PDT´s eventually, but I see this as another option, another tool, also maybe useful for some other people, that´s why i posted it. I asked here about the Ibanez switch, but I was discouraged to try it, someone said it wouldn´t work...
The momentary footswitches I can get here are for electrical purposes, they don´t fit in a PCB, the terminals are not meant to be soldered.
Also, I´ve had pop problems with 2PDT switches (made here, not imported), and I wanted the certainty that the switch wouldn´t pop (yes, i know about pulldowns, etc. I have read the whole forum!!! Yes, all of it!!! 500 some posts!!!) .
I don´t think it would be a good idea to put the switch in the same board as the effect, the result would be too big, having two separate boards gives you more flexibility with the internal layout of the box...
ALSO, I´m trying to finish my first pedal (Ross comp), and this was the best option i found for the switching...I´ve already made the Tone god switch, the DOD one, none of them worked to my entire satisfaction (actually, the DOD one didn´t work at all)

[Unbeliever]

You are posting on an internet message board, and 3PDTs are sold on that same board by mail order.
Smallbear ships to South America as do others.
I dont see the problem.

I can think of a few good reasons why an electronic switch would be preferable to a mechanical 3PDT, but obviously you know what these are and have considered them of no value before making your post.

Moroctopo, this is a good effort if you're just finishing your first pedal. Some people don't seems to realise the economies of purchasing might be different outside their own country. ;^)

[Nasse]

Nice board, good it looks

[markr04]

Thank you for sharing this, Morocotopo! If that's not DIY, I don't know what is.

[bioroids]

Buen trabajo che!

Tene en cuenta que la mayoria de los Fets y transistores mencionados en el circuito aca no se consiguen, o salen carisimos. No hay ninguna necesidad de usar los mismos; por ejemplo para los 2SK30 podes usar PN4393 (creo que son mejores incluso). Para los transistores de entrada y salida podes usar simples BC549C, o incluso darlingtons (MPSA13 creo que sirven) que te permiten aumentar la resistencia de entrada R2 para que tengas menos perdida de sonido. Lo unico, fijate que tengan la misma distribucion de pines al montarlos.
Para los 2SC1815 del flip flop podes usar casi cualquier transistor NPN y va a funcionar igual. 2N3904 pueden ser una buena opcion, te diria que uses los mas baratos en esa posicion.

Saludos

Miguel

PS: sorry for the non-spanish speakers!

[Peter Snowberg]

GREAT work Morocotopo !

[Elektrojänis]

Sometimes it is good to have this kind of an alternatives in your "pocket" (even if you can get good switches of any kind).

Another thing is... When building stuff just for fun, sometimes it's fun just to try stuff like this even if it is not tonally transparent and stuff. I have built a condenser microphone just to see if it would work. I even built the microphone capsule myself from some old hard disk parts and some other junk and I used aluminium foil for the diaphragm. It's not hifi (and I could probably buy a better mic for 50€), but it works and I'm proud of that. It actually works better than I assumed.

Awww... Sorry for OT... Anyway, my point is that sometimes it's worth it to build something just to see if you can and explore it and tweak it etc even if it has no practical use.

BTW. This could be probably modded to switch between two different effects and then modded to do the switching slowly... I think it could be usefull to have one sound fade away while other fades in.

[JimRayden]

BTW. This could be probably modded to switch between two different effects and then modded to do the switching slowly... I think it could be usefull to have one sound fade away while other fades in.

Excellent idea, I can't wait to see someone implement that.


Oh by the way Jänis, I'm interested in that condenser mic project, can you point me at the right direction? PM me

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Jimbo

[Morocotopo]

Bioroids:
Gracias compatriota! Voy a tener en cuenta tus sugerencias sobre los componentes, me vienen muy bien. Apenas lo haga funcionar (si funciona!), comento mas noticias. No entiendo muy bien lo de los darlingtons (en realidad, no se que es un darlington... ejem...). Que valor tendria que usar para R2 si uso un darlington (creo que es un tipo de transistor, correcto?) O depende de que darlington use?  Usar un darlington mejoraría la performance de audio del circuito (menos perdida de señal)? .Ahora me voy a tomar mate con dulce de leche y a escribir con mi boligrafo...he, he

To the others:
Thanks for the responses, as soon as I get it to work, I´ll post news. Practice your spanish! ( )
Anyone need translation?

[Peter Snowberg]

Trabajo fantástico Morocotopo !      

[Morocotopo]

By the way, I forgot to mention that the electrolitic (polarized) caps C4, 5 and 14 were not indicated as such in the original schem by RX5, they didn´t have polarity indication, I added their polarity after looking at another Boss schematic on the net. Also, I have doubts about C6, C8 and C13, in the other schem I saw their values are:
C6: 0.047uF
C8: 0.047uF
C13: 0.01uF
Problems with the translation between nF and uF? I guess I´ll try both values...
And, I couldn´t find the 1N4146 diode, I was told that BY255 is a substitute, what do you think?

[Morocotopo]

Muy bien tu español, peter!!