chunk chunk pcb parts

[Ohioisonfire]

I want to build the chunk chunk distortion pedal from madbeanpedals, but when I went to look for the parts on the website I use i was really confused.  I really have no idea which resistors, capacitors, etc. im supposed to buy.  Any help will be greatly appreciated.    this my first non-kit build and I don't want to mess it up by ordering the wrong parts.

[Govmnt_Lacky]

Here is a quick, down-n-dirty to help you out. You can use Google to find places to get the parts. If you can purchase the parts from the store on this site, it would help Aron but some things are just not available so you will need to go elsewhere.

Resistors - You can use 1/4 or 1/8 watt sizes. Most layouts you find mentioned here make room for 1/4 watt resistors. You can use metal film OR carbon. Up to you.
Caps - USUALLY, anything below 1uF is a film or ceramic disc type cap. Anything above (10uF, 100uF, etc) are aluminum electrolytic type caps and these are polarized which means they have to be installed a certain way.
Trimmers - These are just small potentiometers (usually liner taper) the chunk chunk is designed to use Bourns 3386-style trimers. You dont HAVE TO use Bourns as other manufacturers produce the same types as well.

As for the other items (transistors, diodes, etc.) you can just Google the numbers and you will find them.

As you build, you will learn what you can and cannot do. Also, you will learn what you can and cannot use.

Good Luck 

[Ohioisonfire]

What about voltage for the capacitors?

[Govmnt_Lacky]

What about voltage for the capacitors?

As long as it is ABOVE the voltage that is being used in the circuit (chunk chunk can run on 9V, 12V, and even 15-18V I believe) you will be good.

If you plan to just run it at 9V, then any cap at 16V or above should be sufficient.

[Ohioisonfire]

Two last questions for now, when I look at the wattage for the resistors they all say , 06 watt.  Is that not right?  Also, should it get "axial" or "radial" capacitors? 

[Govmnt_Lacky]

Two last questions for now, when I look at the wattage for the resistors they all say , 06 watt.  Is that not right?

Doesn't sound familiar. They may be 1/6 watt which are uncommon. Can you link to the site or place where you got them?

Also, should it get "axial" or "radial" capacitors? 

Radial is what is used on the chunk chunk and they are the most comonly used on layouts.

[Ohioisonfire]

When I look at the pcb for the chunk chunk it shows rectangular spots for the caps, that's why I was wondering about radial or axial.

http://www.musikding.de/ - thats the site

They seem to have everything I need, just a few different versions of each. Maybe it would be better to order from Aron?

[KazooMan]

I just had a quick look at the parts list and I am certain that Smallbear has everything you would need.  

I looked at the layout and board and I see that the spacing for most of the resistors corresponds to 1/4 watt.  There are some resistors with closer spacing of the holes.  The usual way to deal with this is to have the resistor "standing up".  Just bend on of the leads down along the side of the resistor and put the leads through the holes.  For a nice looking build, try to have all of them leaning in the same direction and at the same angle.  Otherwise it looks like you didn't really care (still sounds the same ).  As was mentioned above, it won't matter whether you use metal film or carbon resistors.  The 5% resistors will be fine, but you can go for the 1% if you want to.  

As was mentioned there are two electrolytic caps, C14 and C20.  The other caps could be the low voltage panasonics from Smallbear, or the box shaped Topmay caps.  The latter look pretty cool.

Smallbear has all of the pots EXCPET the 2.5K linear pot.  The build notes tell you have to modify a 5K pot to make it approximate the desired 2.5K.

Don't forget you will need an enclosure box, jacks, stomp switch, LED (with a bezel perhaps), a DC input jack, wire, a battery clip (maybe a battery holder), and the board from MadBean unless you plan to etch your own.

Let us know if you have any more questions.  This looksl like a fun build.

[Govmnt_Lacky]

When I look at the pcb for the chunk chunk it shows rectangular spots for the caps, that's why I was wondering about radial or axial.

http://www.musikding.de/ - thats the site

They seem to have everything I need, just a few different versions of each. Maybe it would be better to order from Aron?

Those are still RADIAL caps. They are just the "box" style like KM mentioned.

I have never ordered from that site. Maybe someone can chime in and explain.

[KazooMan]

I have looked at the MadBean build instructions and I don't see anywhere that he refers to a wattage for teh resistors.  1/4 watt is pretty much standard for pedals like this.

Also, the notes mention two parts that have uncommon values and give you instructions on how to deal with that issue (putting two resistors in series in one instance and two caps in parallel in the other).

Yes, you want radial caps.

Yes, Aaron will have most of what you need and it would be nice to support him.  I haven't checked to see if he has everything.

[Ohioisonfire]

So C14 and C20 are both radial electrolytic caps and the rest are the "box" shaped ones?

I ordered one of the fuzz kits from that website and a couple LEDs, but that's about it.

[KazooMan]

Yet another couple of comments.

You want to get 16 mm pots since there are six of them in this pedal.  You could go with 24 mm pots, but you will need a much larger box.  Do some planning before you decide on what size box you need.  Things get crowded pretty fast!

I mentioned the box-shaped Topmay caps above.  I like the look of them and they have worked well for me.  

[Ohioisonfire]

Does pot size affect sound, function, etc.?

[Govmnt_Lacky]

Does pot size affect sound, function, etc.?

No. 16mm pots are suggested because if you use 24mm pots then the enclosure would need to be HUGE! 

Unless you want to have a crowded control set, I would recomend building this in something like a 1590BB size enclosure or larger.

[KazooMan]

A few guys might argue that you can get a bit finer control with the larger pot since the length of the contact inside is longer.  I think that in order to achieve this you would need correspondingly huge knobs top allow such delicate adjustments.  In practice, for a pedal you probably couldn't tell the difference.  The difference in diameter may be only 8 mm, but remember, the size of the lugs and their mounting insulator are larger as well and the pots are thicker.  When you think in all three dimensions you soon realize that the larger pots take up a huge amount of extra space.  You can often have the contacts of a jack or a section of board over the top of a 16 mm pot.  With a 24 mm pot in the same box you might run out of real estate.  Go for the 16mm pots. 

If you find a time when all of the "sweet spot" for a given pot is concentrated in a small portion of the range, it is a sign that you need to rethink the value of the pot!

[Ohioisonfire]

Alright  thanks SO much guys!  You've both been A LOT of help. I think I'll order the parts tomorrow.  Does anyone know how this pedal sounds?  Just wondering..

[smallbearelec]

I really have no idea which resistors, capacitors, etc. im supposed to buy.

When you wan to build something from Madbean, Tonepad, Generalguitargadgets, Runoffgroove, etc., e-mail us at smallbearelec@ix.netcom.com and ask for a parts list. Our "library" is pretty extensive at this point, and each spreadsheet includes SKU numbers that make shopping easier. As you get used to shopping in my store, it will be clearer what kind of parts you need for a given function, and you'll be better able to source from other catalogs as well.

Regards
SD

[KazooMan]

Well, who woulda thought!  I never knew that Smallbear had pedal specific parts lists after ordering about a gazilliion parts from them.  One more reason to give a big "thumbs up" to Steve and Smallbear for being there.  The same goes out to Aaron for providing parts for all of us boutique pedal builders. 

I would have to admit that I have always felt a bit of reluctance (shame) at ordering just one piece when that is what I need.  I imagine someone searching through the inventory to find the exact part and then putting it in my order basket.  I usually order two to ten times what I need depending on the price of item (not for an pricey oddball item).  The net result is an inventory of parts that allows me to build many pedals without placing any orders, or a chance to "jump start" the build while I am waiting for the last parts. 

Parts are pretty cheap.  I recommend buying more than you think you will need. 

Therein lies a new thread!

[Ohioisonfire]

Thanks guys (small bear, I sent you an email)