Zvex Machine debugging.

[markbee]

I just finished my project and it has one major imperfection, it doesnt work at all.
Well it bypasses as it should, led is working, but when i enhance the effect it just cuts the signal off.
I have no idea where to start searching. I think it should be grounded properly, i soldered everything labeled "ground"
to input jack sleeve/shield. I did this according to this layout http://tagboardeffects.blogspot.cz/2012/03/zvex-machine.html and
the offboard wiring is number 5 on this site http://www.tonepad.com/getFile.asp?id=76 .
Please tell me what to do, or how to follow the singnal path to find out what is causing the problem. Thank you

[LucifersTrip]

I have no idea where to start searching.

The first thing you would do is hit the debugging thread here...An excellent place to start is by taking voltages at the transistors and comparing to a working one.

Though, I think The Machine is an off limits topic

[markbee]

Well, i went through that topic, didnt find it helpful at all. I really dont know where to start.
Is here anyone who had built this?

[Colonel Angus]

I have no idea where to start searching.

Though, I think The Machine is an off limits topic

Do go on...

[Mark Hammer]

As a device intended to produce crossover distortion, there will be diodes (in the form of transistors) in series with the signal, and other transistors intended to get the signal past the needed forward voltage.  That suggests two ways in which transistor pinout confusions/mixups could impede functioning.

[IvIark]

I don't know whether the Machine is off limits here, but if it is just post your transistor voltages on the blog, and if you can a close up front and back pic and I'll see if I can help.

[LucifersTrip]

Well, i went through that topic, didnt find it helpful at all.

that's because you haven't provided the info noted in that topic so WE can help you...mainly:

7.Turn your meter on, set it to the 10V or 20V scale. Remove the battery from the battery clip. Probe the battery terminals with the meter leads before putting it in the clip. What is the out of circuit battery voltage? =>
Now insert the battery into the clip. If your effect is wired so that a plug must be in the input or output jack to turn the battery power on, insert one end of a cord into that jack. Connect the negative/black meter lead to signal ground by clipping the negative/black lead to the outer sleeve of the input or output jack, whichever does not have a plug in it. With the negative lead on signal ground, measure the following:
Voltage at the circuit board end of the red battery lead =
Voltage at the circuit board end of the black battery lead =

Now, using the original schematic as a reference for which part is which (that is, which transistor is Q1, Q2, etc. and which IC is IC1, IC2, C1, and so on) measure and list the voltage on each pin of every transistor and IC. Just keep the black lead on ground, and touch the pointed end of the red probe to each one in turn. Report the voltages as follows:

Q1
C =
B =
E =

Q2
C=
B=
E=

...Q6

[Toney]

  I breadboarded this ages ago and struggled to see the "point" of the circuit vs a decent EQ. I wasnt set up with a switch to hear guitar straight through so
I may have missed somting. Kinda seemed like a whole lotta nothing to me.

On another note, you may be in breach of copyright with your username ( ) http://www.diystompboxes.com/smfforum/index.php?action=profile;u=19437

[Paul Marossy]

I've always thought of the Machine as a Dynacomp + exciter/expander effect that produces crossover distortion. That's what it sounds like to my ears anyway.

[markbee]

I was out of town for a while, I'll post transistor values asap and draw the wiring if you guys see something wrong.

[markbee]

I have briefly made a layout, it all happened in mspaint so dont judge the looks of it.

http://2i.cz/71665872a1

It looks messy but thats how i wired the whole thing. I assume grounding problem or dc jack problem, I used different dc jack than im used to, also LED doesnt light up when im powering it through dc jack, when I run it through batteries, LED works just fine but the sound cuts out anyway.
It would be really helpful if you of you more experienced guys checked that wiring. I really hope to get this work

[markbee]

I just noticed that the middle pin on the footswitch is supposed to be connected to input sleeve (it isnt connected just in the picture).

[AudioEcstasy]

I had a similar problem with a recent build. Check your grounds, power, and for any loose spots in the wiring.

[markbee]

so I decided to rewire it according to this: http://home.centurytel.net/flanneldrawers/mbb-wiring-diag.jpg

So correct me if I'm wrong, i connect everything that should go to the ground right to the output sleeve? I mean ground from potentiometers and from PCB.
And what shall i do about the PCB output, on the diagram it goes from pcb to the Output pot 2nd lug and on the wiring layout it goes from swtich to PCB, how shall i do it?

[IvIark]

Is the circuit working?  I'd check that before you think about wiring in the switch or you're giving yourself another potential cause of failure.  Just connect the input and output from the board directly to the input and output sockets first, use a terminal block like this:

http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Mark%20Builds/1012110003_2.jpg

All the grounds need connecting together, board, input and output sleeves, pots and DC adapter so either solder those connections in or again use a terminal block to temporarily connect them while you're testing.

[markbee]

I havent really worked with terminal blocks and I dont have them. So how do I connect the output?
I think that theres just problem with grounding since no signal is coming through at all. I just want to wire it straight on and see what it does this time, but im not sure about wiring the output.

[IvIark]

The output wire of the board goes to lug 3 of the Out pot, lug 1 goes to ground, and lug 2 is the real output to the switch

[markbee]

Thanks. And what is the ground here basically? Everything I thought was correct seems to be be completely wrong.

[IvIark]

The grounds are all connected together, either in a star formation to a central point or daisy chain between them all.  So board grounds (2 ground wires from the board), DC socket, input and output sleeves, pot grounds, and ground for LED on switch all need connecting.  Daisy chaining is probably easier then you only have a maximum of 2 wires that need soldering to each point of ground, the in and the out.  Or if you want to take them to a central point then the input and output sleeves are probably a good choice because they can take plenty of heat without damaging them.  Or you could even solder a wire from every point of ground to any of the free holes in the top or bottom rows of the board which are both ground rails.

[JRC4558D]

so I decided to rewire it according to this: http://home.centurytel.net/flanneldrawers/mbb-wiring-diag.jpg

So correct me if I'm wrong, i connect everything that should go to the ground right to the output sleeve? I mean ground from potentiometers and from PCB.
And what shall i do about the PCB output, on the diagram it goes from pcb to the Output pot 2nd lug and on the wiring layout it goes from swtich to PCB, how shall i do it?

that draw is cool but they forgot to put the GND cable from the INPUT sleeve to the BOARD then if you did exactly like that your PCB has not power at all. Use the INPUT sleeve as a STAR GND and put just a piece of cable from there (Input Sleeve) to your PCB GND Rail and it should work if everything else is OK.

Cheers.