Sparkledrive Build not working properly, needs verification plz

solarplexus · May 30, 2007, 09:41:15 AM

Hi guys!

OK, first of all, my intentions are only to verify why my built is not working properly, I mean NO DISRESPECT to Torchy who worked hard to build the vero for this pedal. I don't remember where I got the layout, but here it is and PLEASE Torchy, let me know if you want the link removed from both this forum and the photobucket.

http://i179.photobucket.com/albums/w288/solarplexus311/ba209cfb.gif

Is there any errors in that vero layout?? The tone control does NOTHING to the sound and the blend control is way too much over the clean side, although when completely off, there is the overdrive sound but it is fainter and fades fast as the pot blend is turned clockwise.

Would you have any idea what would cause this?? Is it the vero layout that has errors ??

Thanks for your help,

Matt

solarplexus · May 30, 2007, 09:47:43 AM

I must add that I substituted the MPSA18 for a 2N5089 and R9 for a 2.2k but I'd believe it wouldn't change much, right?

markm · May 30, 2007, 09:56:08 AM

First, I know nothing about Vero stuff although, it does remind me of a "permanant breadboard" type of thing which could be kind of cool.
I used Torchy's schem as a reference when doing my PCB Layout for this circuit as well as one other and I beleive the schem is correct with one exception.
Lug 1 of Clean B and Lug 3 of Clean A need to be tied to Vb.
Other than that, I beleive it's good to go.
Although this circuit isn't overly complicated, it can be a PAIN to get it sorted out. I think I ended up revising my Layout about 3 or 4 times before it was posted to get it correct.
I also can say, to my knowledge Torchy as well as several others have built the Torchy vero with success.
If it helps at all, you can reference my PCB circuit......it may help you.

http://aronnelson.com/gallery/album76/SparkleDrive_LAYOUT

solarplexus · May 30, 2007, 09:59:46 AM

Well... I might as well just etch yours and save me some time debugging...

markm · May 30, 2007, 10:02:02 AM

Quote from: solarplexus on May 30, 2007, 09:59:46 AM
Well... I might as well just etch yours and save me some time debugging...

Okay.
It works anyway!

solarplexus · May 30, 2007, 10:03:49 AM

Ok I just saw something, the output cap on your layout is 2.2uf and the one from Torchy is 47uF... might not explain everything, but might explain that some parts values are not correct

markm · May 30, 2007, 10:08:41 AM

Quote from: solarplexus on May 30, 2007, 10:03:49 AM
Ok I just saw something, the output cap on your layout is 2.2uf and the one from Torchy is 47uF... might not explain everything, but might explain that some parts values are not correct

No.....they're both 2.2uF.

spudulike · May 30, 2007, 05:47:18 PM

On the veroboard layout, the clean pot does go to Vref, just doesnt on the schematic.

Edit

Checked the Vero layout again, and the Tone pot wiring is wrong.

Torchy has the Blend pot A(1) and the tone control (1) labels "upside down" ... it should be wired like this .... just swap the two wires over.

Tone & Blend controls should work ok now, dont see any other errors ...

solarplexus · May 30, 2007, 09:00:15 PM

Thanks Hugh, I'll try that and keep you posted!

solarplexus · May 30, 2007, 09:46:16 PM

ok I made the switch and it now works~!! Thanks!

However, I still think the OD side gets clean too quickly with the blend knob... is this normal with this pedal or not ?

MartyMart · May 31, 2007, 04:30:34 AM

Quote from: solarplexus on May 30, 2007, 09:46:16 PM
ok I made the switch and it now works~!! Thanks!

However, I still think the OD side gets clean too quickly with the blend knob... is this normal with this pedal or not ?

Are you using a dual 100K B linear pot ??
That would be quite even, where as a Log pot would seem bunched up one end !

MM.

solarplexus · May 31, 2007, 07:53:26 AM

I'm using a:

Pot Alpha Dual-Gang 24mm REVERSE Audio Taper 100K

from Smallbear...

markm · May 31, 2007, 08:06:26 AM

Quote from: solarplexus on May 31, 2007, 07:53:26 AM
I'm using a:

Pot Alpha Dual-Gang 24mm REVERSE Audio Taper 100K

from Smallbear...

No good.
You'd want a Linear Taper pot for the Blend.

solarplexus · May 31, 2007, 08:31:42 AM

Oh... I'll order the good one then.

What can I build with this kind of pot??

MartyMart · May 31, 2007, 09:45:55 AM

Quote from: solarplexus on May 31, 2007, 08:31:42 AM
Oh... I'll order the good one then.

What can I build with this kind of pot??

Reverse audio pots are great for gain controls, things like Rat/Dist+/Liquid drive etc etc
You'll get a VERY nice smooth range from that, or look for a DIY circuit which has
2 x stages that need a gain control, so you use both half's of that pot.
See Mark Hammers posts on changing the Dist+ type 1M gain pot for smaller - works
just as well with a couple of tweaks.
MM

solarplexus · May 31, 2007, 09:51:44 AM

Do you have any idea what project could be built in that manner?

spudulike · May 31, 2007, 10:01:34 AM

Quote from: solarplexus on May 31, 2007, 09:51:44 AM
Do you have any idea what project could be built in that manner?

Roseyray.

markm · May 31, 2007, 10:28:51 AM

Quote from: spudulike on May 31, 2007, 10:01:34 AM
Quote from: solarplexus on May 31, 2007, 09:51:44 AM
Do you have any idea what project could be built in that manner?

Roseyray.

Does that one use a reverse Audio Taper?
Without looking at the schem and not remembering it all that well, I thought it was linear?

solarplexus · May 31, 2007, 10:44:07 AM

Looking at the Roseray schem, the tone pot is 250K lin, but not dual either...

spudulike · May 31, 2007, 05:21:54 PM

Sorry, got that schem on the brain at the moment - I've breadboarded it and am messing with a couple things.

I meant the Crank (same designer though), and thought a rev log dual might be interesting. The only C dual I can think of is the Neovibe. Might be interesting to maybe run two Dist+ or Dod250 into each other, use the dual rev as a gain control but anti-wired like the Crank ?

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Sparkledrive Build not working properly, needs verification plz