popping in mosfet boost vero

[upspoon12]

Hey everyone.

Just built an amz mosfet boost on vero using the sabrotone layout http://www.sabrotone.com/wp-content/uploads/2011/05/AMZMosfetBoost.gif



It works as it should, i have it wired up for true bypass instead of buffered bypass and am getting a wicked popping when i hit the switch
I figured the 10M resistor to ground would have covered it, but on second look maybe its that 1M r6 to ground that needs to be upped?

For the true bypass i made the following changes:
On/Off SW.2 now = Ground
On/Off Sw. 6 now = Output
On/Off SW.4  = no longer used.

Any light you guys could shed on this would be awesome! Thanks!

[bloxstompboxes]

I hate vero but it looks as if R1 does not go to GND but from your input cap C1, c5 and then to R3. I would through a 1M or better from Input to GND. You should have a pad under R7 to connect to the input and then anywhere on your GND strip.

[upspoon12]

I hate vero but it looks as if R1 does not go to GND but from your input cap C1, c5 and then to R3. I would through a 1M or better from Input to GND. You should have a pad under R7 to connect to the input and then anywhere on your GND strip.

your absolutly right. i forgot about the cut under the fet that prevents the 10M resistor to go to lug 2 of the pot and thus to ground.
will definitely give this a shot! thanks~!

[upspoon12]

ivwe got a 10M resistor in there direct from input to ground and still popping

[bloxstompboxes]

Would help to have the schematic but I think that 10uf cap is gotta be were it is coming from. Try another resistor from your ouput to gnd. It's discharging whenever you hit the switch. The resisitor should take care of it.

[upspoon12]

yeah unfortunately i don't have a schematic for this, apparently it was buffered output originally,  which according to the guy that made the vero (can't get ahold oh him) c4 and R6 were for the buffer and not necesary, but in a post on the site it says they shouldn't really impact anything leaving them on the board,

i aligator clipped in a 10M resistor from OUTPUT to ground as well, still popping.


Bad switch?

[induction]

It's not clear to me how your true bypass mod works. As far as I can tell from what you've written, you're not switching the input at all?

Can you clarify or draw a diagram or something?

[upspoon12]

Sure.  Here's what the wiring looks like.  

http://imgur.com/bEgHEWf

[bloxstompboxes]

That wiring setup does not ground the effect input when in bypass mode. I use the 5th wiring scheme in this link. It is true bypass and grounds the effect input when bypassed. I believe that is your issue now that I have seen the wiring diagram you posted. Someone else have any input?

http://tonepad.com/getFile.asp?id=76

[R.G.]

I always put at "VERIFIED" image on all my vero diagrams.   

[upspoon12]

well i've switched the wiring technique for true bypass so that the effect is grounded when in bypass, it still is popping and now has developed a really high (10khz) hiss.


any other ideas? i can provide pictures of my handywork if necessary

[bloxstompboxes]

I think pics at this time might be helpful. Seems smething else is going on here. I have no experience in vero and nor do I want any so maybe someone esle should chime in here. However, I think RG maybe hinting at something though, no?

[upspoon12]

Sure  here are a couple photos


http://imgur.com/uWcEiBd
http://imgur.com/QhkQifU

I wasnt sure if he was hinting or not.  Haven't really been around long enough to know who is who and what is who's what

[induction]

I don't see a connection to ground on your board. I see connected grounds between the jacks, the adapter, and the switch. But the ground wire on the board seems to join two ground points, while making no reference to any of the other ground points. Maybe it's hidden in the pictures?

[upspoon12]

I have the pot grounded on the board via a connection from A1

and i have the board grounded via a connection at f15.
however i just realized that the connection is soldered together with the switch and the pot ground then to the output jack main ground point which is then tied to the ground on the power sup.

Perhaps i should link them all directly to only the output jack then the tie to the power source?

[garcho]

First go here:
jack's page
He mentions utilizing the buffered output or unbuffered output depending on your situation, but this is not a "buffered effect" a la Boss switching. You shouldn't change anything to make this true bypass. This circuit IS the buffer, what he probably means by buffered is the non-inverting and lower output impedance of the common drain configuration, as opposed to the inverting common source configuration.

[induction]

First go here:
jack's page
He mentions utilizing the buffered output or unbuffered output depending on your situation, but this is not a "buffered effect" a la Boss switching. You shouldn't change anything to make this true bypass. This circuit IS the buffer, what he probably means by buffered is the non-inverting and lower output impedance of the common drain configuration, as opposed to the inverting common source configuration.

I disagree. The layout is done in a way that switches between output 1 and output 2 for boost and buffered bypass, respectively. Justin has modified his layout to standard true bypass switching. This should work fine.

I don't see a connection to ground on your board. I see connected grounds between the jacks, the adapter, and the switch. But the ground wire on the board seems to join two ground points, while making no reference to any of the other ground points. Maybe it's hidden in the pictures?

I'm still confused about how ground is reaching the board. I see that the pot is attached to the 'ground' row of the board via A15, and that rows A and F are jumpered together with the darker green wire. But I don't see how the ground from the switch, the jacks, and the adapter gets to the board. Is there a soldered connection inside the black tube?

[upspoon12]

I do understand that it is itself buffered, however i was looking to bypass the circuitall together and only insert the circuitry when i am wanting to boost. I have built a couple of the PCB's that Mr. Orman makes and done it this was many times with no issue.

But for some reason the vero layout gives me huge problems with this. i've built three of them with the same issue.

I pulled the vero layour from sabrotone and in the comments on the page there were notes about making the changes that i noted on the paper to make it to true bypass instead of using it as a buffer/boost.

I suppose if all else fails i'll just rewire it the way its supposed to be and deal with the buffer.

[upspoon12]

I don't see a connection to ground on your board. I see connected grounds between the jacks, the adapter, and the switch. But the ground wire on the board seems to join two ground points, while making no reference to any of the other ground points. Maybe it's hidden in the pictures?

I'm still confused about how ground is reaching the board. I see that the pot is attached to the 'ground' row of the board via A15, and that rows A and F are jumpered together with the darker green wire. But I don't see how the ground from the switch, the jacks, and the adapter gets to the board. Is there a soldered connection inside the black tube?

yes the three of them are soldered together via  cut in the insulation and the wires put together.

[induction]

Have you tried disconnecting the led?