help with FatPants (ver. 2) build sheet.

[impetus maximus]

hello everyone

this is my first pedal build. i'm going with the FatPants.

PCB isn't available. What do you recommend?
i'm going with Xicon 1/4W metal film resistors.
C2/C3 Panasonic ECQ-V1H223JL?
C4 ECQ-V1H104JL?
512-J201D27Z good for the transistor?
Bourns 3362P-1-503LF trim pot?
Volume 16mm 100kB Potentiometer (linear taper?)
Fat 16mm 10kB Potentiometer (linear taper?)

i can get everything above from mouser.
not sure which enclosure to get and where from.
was going to ask about switching but i don't think i'll ever turn it off  

TC1044SCPA is back ordered can i wire without it @18v?

C3 is calling for a 22nF (0.022uF) which is what my amp has for coupling.
would going to a higher value (double) make a difference?
i'm thinking of putting in a socket so i can switch caps out.
or possibly run two parallel with a switch on one.

thanks for reading
/max

[jkokura]

Parts for C2/3/4 look fine. The J201 is good too, as is the Trim pot and pots.

For enclosures I always recommend Pedal Parts Plus. You could go with either a 1590B or a 125B depending on what you wanted to do for the layout. Pedal Parts Plus is also a great place to get your switch, jacks, power stuff, and knobs.

You should look into the 7660scpa - similar part. I think Mouser had 126 left when I looked this morning, and they're only 1.11 each.

For C2, you can easily use different values. Going higher will potentially give you a different frequency response. You should try socketing, as you suggest, and trying different cap values - experimentation is part of the reason we do this stuff. The switch idea is a great one too.

One thing we should note is that this stuff we're talking about relates to the Fatpants Version 2.0 - if you plan on building the new PCB when its out you should wait to make your parts order until AFTER you have seen the BOM for the new project. That way you won't leave out any parts.

Jacob

[impetus maximus]

Jacob

i'm going to make the Ver. 2.0 for now. don't need the buffer/higher output.
besides i enjoy soldering, so i prolly make a ver. 3.0 later on.

i'm going to hold off on the enclosure until i see how big my layout will be.
what are my options besides etching a board?

would it be possible to skip the pump and wire the pedal for a 18V input?
if not i'll order the TC7660SCPA.

C2? the PDF talked of switching C3 around for different tone filtering
i dig the experimentation aspect. i pulled my .0022uF coupling capacitor
in my amp and kept doubling the value until i settled on a .022uF.
what a difference!

thanks so much for the help  Jacob
/max

[jkokura]

You could get someone else to etch your board... or find someone with a spare v2 that's been manufactured. Or you can do your own layout in Eagle and have it manufactured.

Yes you can skip the charge pump. That kind of mod is a little bit more involved though. In this case it's just as easy to spend the extra dollar and get a charge pump in there, then you can run it off the more typical 9V supply. If you do insist, what I suggest is using a breadboard to build the circuit first with your 18V supply and potentially look at doing your own layout on Vero or through Eagle or something like that. Considering this is your very first pedal, I don't know if that's up your alley. Keep in mind that's just my suggestion, and you can use an existing layou without the charge pump and with the 18V power supply. There may be some parts you can leave out as well.

Yes, C2 was a typo - it would be C3 that matters there. Remember that Amps and pedal are not the same - doubling or halving parts may not have the same results you experienced in your amp build.

Your welcome, welcome to the forum!

Jacob

[impetus maximus]

i'm going to build a breadboard testing rig.
i caught the building bug with my amp (1W self split (12AU7) FireFly)
building pedals will feed my addiction at a fraction of the cost of building amps 

when it comes time to build i'll prolly go the Vero rout to make modding easier.

your right, for $1 i'm just going to use the pump to make it simple and compatible.

thanks for the advice and warm welcome Jacob
/max