sound on bypass, but not when engaged......

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sound on bypass, but not when engaged......

Postby travisthedog » 09 Jun 2012, 11:52

So I'm a relative noob to this building lark but have built a few "kits" but I have one at the mo which is really doing my head in!

It's a zvex super hardon clone so pretty basic, but when its in bypass the signal passes to the amp, but when its engaged, the led lights but there's no sound. There's power at the 9v socket, power at the board and no apparent shorts on the Vero, but, when switched on, no power at the switch. The 9v comes from the power in through the led and then through a 4k resistor to the footswitch. There is no power beyond the resistor (at the fs) when the switch is on, but there is when its off.

Any ideas?
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Re: sound on bypass, but not when engaged......

Postby Seiche » 09 Jun 2012, 12:02

transistor in backwards?

what do you mean by saying "there is no power at the switch"?
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Re: sound on bypass, but not when engaged......

Postby travisthedog » 09 Jun 2012, 12:11

Seiche wrote:transistor in backwards?

what do you mean by saying "there is no power at the switch"?

Transistor is ok.

I mean that (rightly or wrongly) I assume that in bypass the switch stops the power going to the circuit. So when engaged I lalso assumed that there would be a power reading on one of the pins of the 3dpt to send the power to the circuit. Like I said. There is power at the 3dpt when the switch is off
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Re: sound on bypass, but not when engaged......

Postby Seiche » 09 Jun 2012, 12:17

travisthedog wrote:I mean that (rightly or wrongly) I assume that in bypass the switch stops the power going to the circuit.

no, there is power to the circuit as soon as you plug in the input jack in a standard wiring with a battery. The battery supplies power to the circuit not the switch.

Can you post pictures of the board? Which layout did you use?
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Re: sound on bypass, but not when engaged......

Postby travisthedog » 09 Jun 2012, 13:05

I can't really post the schematic as I'd get into allsorts of trouble, but let me re assed with the guitar leads plugged in and report back.......
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Re: sound on bypass, but not when engaged......

Postby Seiche » 09 Jun 2012, 14:03

:scratch: why would you get in trouble? And by schematic you probably mean layout, no? Because the schematic has been posted dozens of times here.
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Re: sound on bypass, but not when engaged......

Postby travisthedog » 09 Jun 2012, 14:58

Only because it was bought from a company and I assumed there would be copyrights over their layout pictures that they send out with each kit?
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Re: sound on bypass, but not when engaged......

Postby Seiche » 09 Jun 2012, 15:11

it's just an SHO. there's only so many ways you can arrange one transistor and a few components. Which company is the kit from?
Post pictures of the board and footswitch wiring then, they are your own copyright (because you own it and took the pictures).

otherwise no one will be able to help you if all you're providing is "it doesn't work".
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Re: sound on bypass, but not when engaged......

Postby DrNomis » 09 Jun 2012, 17:14

Could be a faulty footswitch, this would also explain the "no sound when engaged" issue, I'm guessing that you used a 3PDT footswitch, if so, what you need to do is engage the effect without a battery installed, next set your multimeter to a low-ohms range and then check the contacts to see if you're getting continuity where you're supposed to, if it looks like you're getting open-circuits where there should be continuity, then replace the footswitch with a new one, sometimes those 3PDT footswitches end up with lose contacts if too much heat is applied while soldering, leading to faulty and unreliable contacts.... :thumbsup
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Re: sound on bypass, but not when engaged......

Postby modman » 09 Jun 2012, 17:57

http://diy-fever.com/misc/audio-probe/
Seiche wrote::scratch: why would you get in trouble? And by schematic you probably mean layout, no? Because the schematic has been posted dozens of times here.

This git has gotten his kit from a website that is careful not to mention brand names... or organize a support forum. I suppose, let's not get into the trouble.... :mrgreen:
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