Help with Smash Drive

[zener]

I'm a newbie and this is my first attemp to build one.

My Smash Drive is not working. I'll actually try to build the Audio Probe to check out the whole circuit. For the mean time, I want to take chances that someone here might help. Here it goes:

I build the Smash Drive from http://www.generalguitargadgets.com/v2/diagrams/smashdrive_lo.gif and have it first in a breadboard. The circuit is quite simple (few components). The only difference with what I did is that I have a DPDT switch instead of a 3PDT as stated in the layout. I don't even have a LED and a DC jack.

I wired the whole thing using the basic or elementary bypass as what I read somewhere in Aron's homepage. I used the #2 pin of the treble pot as the effect input and the point connected to the .005uf cap as the output, something like this:

bypass -----------------l     l------------bypass

input jack --------------l     l------------output jack

#2 pin treble pot-------l     l------------ .005uf cap          

I really suspect the whole problem is with the switch wiring. In the 3PDT switch, I saw a point or two which are connected to the ground. I have nothing from the switch going to the ground, just what I describe above.

I already know the Millenium Bypass but it uses a transistor, diode and few resistors that I don't have now (until I get some money again).  

Please help. I know this one is even less than a piece of cake to most of you.

Thanks for any help :wink:

[petemoore]

I had some troubles with getting the IC in the right way...
 Just compare your 386 pinout to ground [compared to the schematic and your build], that should get it in the right way...mine had the opamps locator dot on the top left as you look down on the boarrd.

[RDV]

Follow this diagram & it will work if you have no other mistakes.
http://www.generalguitargadgets.com/v2/diagrams/switch_lo_dpdt_std.gif

Regards

RDV

[zener]

RDV,
I can see that wiring clearly, but I can't tell which are circuit input and output in the layout  http://www.generalguitargadgets.com/v2/diagrams/smashdrive_lo.gif. Can you tell me those things, I'm such a newbie.

Thanks :wink:

Zener

[Chris R]

If you go here:

http://www.diystompboxes.com/cgi-bin/webbbs_scripts/webbbs_config.pl?read=329

and look at the schematic.. it shows the input goes in to the .005 uf cap then to pin 3 of the ic (lm386)..

so then if you look at the generalguitargadgets link again.. you'll see the input going into the .005 uf cap.. or the green wire.

the output would be the orange wire comming off of the middle lug on the treble pot.

Chris

[zener]

Now I got it. I had it inverted :roll: . Thanks everyone, especially Chris for pointing it out.

Now it is working, I came into another problem.

When I push the switch on, there's always a sudden short (less than a second) burst of strong sound, then it will go to its normal level. While playing with the circuit on, I always get a fading in loud squeal or hiss whenever I stop playing :x . I actually use a karaoke which mic input was modified by my dad so that I can use it as guitar amp. I don't any problem with it putting my guitar straight into it.

By the way, the circuit is still in the breadboard and the wires are kinda tangled but I looked a lot of times for any shorts and there was none.

Is this normal? Does the loud noise disappear if I put into a PCB then in an enclosure? If not, what might be the reason and what can be done?

Thanks for any help :wink: