beginner wanting to build an octave stomp box -help wanted

[loki]

hi everyone, first of all this is an incredible site, full of a lot of useful infos... so a big thank you to aron from me...

well i've never built an effect but there's one that i'd like to build and it's an 1 octave-down effect... through my researches i've ran into several schematics: BOSS OC-2, EH Deluxe Octave, Craig Anderton's Rocktave, etc... but the easiest to build according to me was the Shih-Ei Octave Box whose schematic was drawn by Stellan Lehrberb.

Unfortunately I'm not an expert in electronics so there's some parts of the schematic i didn't understand so i'm looking for an answer for these questions:

1) the resistors are marked with their Ohm value but not with their Wattage and percentage (and this is something i've noticed in most schematics) so what resistor should I get? 1/4W, 1/2W, 2W or what? 1% or 5%?

2) about the capacitors: here again they aren't marked with their type (ceramic, electrolytic, ecc) I'll list them all, so maybe someone can indicate me what they should be:
0.1uF
6.8nF
6.8uF
1nF
0.22uF
10nF
250pF

If you can help me in this i'll appreciate it very much.... maybe i could post the chematic image to make it clearer.... or maybe you can indicate me another 1 octave down schematic that i could build instead.
thank you
bye!

[Kaiowas]

Hi loki!

About the resistors, 1/4Watt should do, almost all the Stompboxes PCBs are designed for that "wattage".

About the Caps, if there's no specific type, then you'll have to look which ones are polarized (generally with a + sign beside them) and which ones aren't, those who are, are electrolytics, and those who aren't, are any non-polarized cap (polyester, ceramic, etc).

Maybe you should post the link to the schematic you're working with, that way I should be more capable of helping.

Hope that help.

[smoguzbenjamin]

1/4W resistors are most space-efficient, but I prefer using 1/2W resistors because they're bigger and therefore it's easier to read the value. We are not in a position where we have to cram half a computer into something that fits into you palm, so it's not necessary to use 1/4W resistors. It's a matter of personal taste I guess.

Any cap bigger than 1uF is likely to be electrolythic. Anything below that can be anything, although I don't like the sound of ceramic caps myself. I prefer metal film caps, they're great

[loki]

thanks guys for your replies,
you solved almost all my problem except for the resistor %.. is there any difference between 1% and 5% resistors? I've seen that for example Craig Anderton's Rocktave schematic lists 10% resistors, but i couldn't seem to find them on the online electronic parts shops...

anyway here's the schematic image.


I have just two more questions,
there are 3 signs on the lower-left part of the schematic with a triangle and a line... what are them??

and, the stompbox is built with two DPDF switches (i've seen an image, they're labeled "normal" and "octave"... would it be possible to convert it to a single DPDF or 3PDF switch?
and the very last question... how do i look for a replacement for the 2SC644 transiston in cas i dont find it?
thanks again for your help
bye!

[smoguzbenjamin]

The triangle and line is a diode. A diode is a one-way-valve for current, but will only conduct above a certain voltage, also called the diode's forward voltage.
A 5% tolerance resistor is within 5% of its stated value, respectively a 1% resistor is withing 1% of what it says it is.
To find a replacement for any transistor use google and search for "<enter transistor number here> replacement". So your google search would be "2SC644 replacement"

[loki]

ok so if they are diodes since they are not marked in the schematic there's no way to know what type they are, is there?

[smoguzbenjamin]

No not by the image, where'd you get it from though, because there might be a reference on the site where it came from.

[GuitarLord5000]

Hi Loki.  Welcome to your new addiction!  :wink:  I hope everything goes well with your new build.  If you have any questions, the guys here are super willing to help.  This site is great!  I would recommend future queries go to the "Building you own stompbox" forum.  That seems to be the most frequented by everyone here and you'll probably get your responses faster.

BTW...You wouldn't happen to be the same loki that frequents homerecordingconnection.com ? (I know, fat chance!)  :lol: