AMZ Mosfet building problem

[Tamir]

hello,

Today I build the Mosfet booster and it was cool.
Soldering went good, very good, the wires as well, I thought I know exactly what I am doing. everything went perfect. I tried the pedal and when I turned the amp ON I got extremely loud noise so I have to close the amp very fast.
I tried evert input-output-jacks wiring combination I think, but I don't know where the problem is coming from! don't know how to check it either.
one thing, maybe I changed between the caps: 0.1 and 0.001 but I don't think it should bother so that it won't work.

please help.

http://aronnelson.com/gallery/album18/AMZ_MOSFET_BOOST_VERO

[MartyMart]

Seems like a straight forward layout, read the "What to do when it doesn't work" stickie and
come back with some voltages etc, that will help solve it MUCH quicker that just "It dont work"

Mean time, check all soldering/parts/pinout/trace cuts/cap orientation
so that you know for sure, you have it EXACTLY like the layout
(the 2 x red squares are "cuts" in the copper strip BTW )

MM.

[Tamir]

1.What does it do, not do, and sound like?
When I turn the amp on and the pedal is connected, I get a very very hard noise so I have to close the amp.

2.Name of the circuit
Amz Mosfet Booster

3.Source of the circuit (URL of schematic or project)
http://aronnelson.com/gallery/album18/AMZ_MOSFET_BOOST_VERO

4.Any modifications to the circuit?
see next

5.Any parts substitutions? If yes, list them.
I used 47k + 22k (69k) instead of the 62k I needed to, didn't have this one so I put something close
I bought all the caps but I couldn't decide which one is the .1 and which is 0.001, so maybe I swiched between them.
I don't know what direction the BS170 should be but I tried them both - I have socket.
I made the cut traces good.

6.Positive ground to negative ground conversion?
No, as it is.

I realy don't know how and what to check with the MM, I don't understand what they say on that topic. =/
If you want more details just tell.

[Tamir]

Note: I soldered everything exactly in its place. I mean, on the layout it says 8 strips x 11 holes, and that's the veroboard I used, so everything is kinda very close, maybe too much?
I notice that just now.

[petemoore]

  I realy don't know how and what to check with the MM, I don't understand what they say on that topic. =/
  I use a test clipped wire to connect the DMM's black probe to a circuit Gnd.
  Or...I use the meter with the test clip I soldered on it's black wire...
  The drain of the transistor should bias to around 1/2v [4.5vdc of a 9v battery].
  use the red lead of the DMM set to appropriate voltage range [20v ?] to measure the voltage difference between the drain pin of the transistor and Ground.
  then measure from gate to ground
  and Source to ground
  The 68k resistor, IIRC is a 'base' value which needs to be adjusted to attain 1/2v bias on the transistor drain...correct me if I haven't read the AMZ article recently enough].

[Tamir]

I am sorry but I am not sure I understood you correctly. the black lead of the MM on the ground, and the red on the drain leg?
if yes, I tried everything on the multimeter and it doesn't give me numbers.

I have a MM that looks exactly like this one, but from another company:

[gaussmarkov]

I am sorry but I am not sure I understood you correctly. the black lead of the MM on the ground, and the red on the drain leg?
if yes, I tried everything on the multimeter and it doesn't give me numbers.

I have a MM that looks exactly like this one, but from another company:

it looks live the 20V setting is at about 10 o'clock on your DMM.  point the selector there.  hook up the power source to your circuit.

now what pete is saying is to touch the ground strip (the bottom one of andy's vero layout marked "ground" on the left of the image) with the black probe and to touch the strip connected to the D of the transistor (the same strip that is marked "in" on the left and "out" on the right--but you need to touch the part of the strip that is between the two cuts).

it sounds like you may not have used a DMM before?  are you able to check the value of a resistor with your meter?

best wishes, gm

[Tamir]

OK, did that, It still shows me 0.00 on the screen, what's wrong?
never used a DMM, but I can check what is the value of a resistor, capicitor not, it doesn't show me neither with caps I think.

[gaussmarkov]

OK, did that, It still shows me 0.00 on the screen, what's wrong?
never used a DMM, but I can check what is the value of a resistor, capicitor not, it doesn't show me neither with caps I think.

ok.  well, while keeping the black probe on the bottm ground strip, touch the red probe to each of the top three strips and tell us what you read.  also, please read the voltage on your battery directly.

--gm

[Tamir]

=/ stil 0.00, what isn't this working? I even tried to change the MM battery. what's wrong here? Is the MM ok?
edit: the first battery is 9.24, the second is 9.77 .

[aron]

Set the meter to DC like everyone said. Put the black probe on ground. Put the red probe on the output of the circuit and see what you get. If the sound is LOUD, it's probably DC from the battery due to a miswired connection.

[Tamir]

As I said, I get no numbers.
I belive I wired the input/output not good, I have a stereo confusing jack with 4 connection, two on each side, I could not decide what connection is tip/sleeve/ring, so maybe it's from there. but it still gets no numbers.

[petemoore]

  To measure a voltage you need two...er batteries.
 The one in the DMM is used as a comparator, so you need one there.
 Then you'll need another source to compare it to, a second battery makes a convenient source.
 Attach the battery to your DMM and you should see a figure in the screen, something like .0 or 0. ...if not I suspect the DMM may be faulty.
 to test a voltage, set the DMM to Voltage range [next bigger selection to the voltage you think you're testing [20vdc on yours], and attach the leads to the battery poles of the battery in test, you should see a voltage reading.
 Attaching the battery to the circuit [loading it] should drop the voltage reading of the battery very sligthly, and testing within the circuit should show voltages between 0v and whatever the battery is supplying.
  If there's a short between V+ and Gnd. in the circuit, it needs to be found before power is supplied [otherwise the battery'll fry], to test for this is another DMM function:
  Set the DMM to diode test [about 5:45 on the dial], just left of bottom there is a --->l--- symbol, with battery in DMM, you should hear a beep when touching the DMM probes together, if the DMM beeps when you touch the poles of the battery clip there is a short between V+ and ground, the circuit won't work, readings will all be about 0v...
  That's why I say see if you can just read a battery voltage of a battery with some 'taste' left in it [should sting your tongue a little bit]. Also the battery in the DMM should be 'tasty', if not fresh.
 I'm hoping you're not experiencing DMM trouble...
 

[gaussmarkov]

=/ stil 0.00, what isn't this working? I even tried to change the MM battery. what's wrong here? Is the MM ok?
edit: the first battery is 9.24, the second is 9.77 .

let me see if i understand you correctly.  you are getting 0V everywhere you make a reading in the circuit, but you read the batteries successfully?  can you figure out why a battery gives approx. 9V reading, yet you get 0V when you read the voltage across the top  and bottom strips?  you should get the same reading because the negative post of your battery should be connected to the bottom ground strip and the positive post of your battery should be connected to the top strip.  unless you have a short circuit. 

--gm

[Tamir]

=/ stil 0.00, what isn't this working? I even tried to change the MM battery. what's wrong here? Is the MM ok?
edit: the first battery is 9.24, the second is 9.77 .

let me see if i understand you correctly.  you are getting 0V everywhere you make a reading in the circuit, but you read the batteries successfully?  can you figure out why a battery gives approx. 9V reading, yet you get 0V when you read the voltage across the top  and bottom strips?  you should get the same reading because the negative post of your battery should be connected to the bottom ground strip and the positive post of your battery should be connected to the top strip.  unless you have a short circuit. 

--gm

exactly, that's why I am not sure I wired the negative lead of the battery to the tip of input, because it seems to not get a negative source on the circuit.
I have a 4 connections stereo jack on the input, I can't decide what is the sleeve/ring/tip...

This is my jack

Sorry about the quality. Can you tell me what number is the ring/sleeve etc?

thank you very much!

[gaussmarkov]

exactly, that's why I am not sure I wired the negative lead of the battery to the tip of input, because it seems to not get a negative source on the circuit.
I have a 4 connections stereo jack on the input, I can't decide what is the sleeve/ring/tip...

all you need to identify are the ring and tip connections.  these are pretty easy.  the ring is the metal that you see around the hole that the plug comes through and the lug for the ring is just a piece of that metal bent up.  your photo is hard to figure out but it looks to me like that is probably #2.

the tip is the band of metal that touches the tip of the plug when it is inserted.  that is the part sticking up on the outside on the right of your picture.  follow the metal down to body of the jack and see which layer it goes into and find the lug that comes out of the same layer.  that is your tip lug.

also, please follow pete's suggestion of checking for continuity.  i suggest that you unhook the battery for this test.  set the DMM selector at 5:45 as pete said and see what your DMM does when you touch the two probes together.  most DMMs make a small beep so that you know that there is a connection without having to look at the DMM.  now use this to see whether your circuit has connections in it that it should not.  for example, when you touch one probe to the bottom ground strip and the other to the top +9V strip, does the DMM say that you have a connection (continuity)?  your voltage readings suggest that the answer will be "yes."  this means that your circuit has a connection it should not have.

and lastly, did you solder your components on the strip side of the vero or the blank side?  you should have used the blank side, even though the diagram seems to suggest the opposite.  i thought of asking this earlier and decided not to, because it is an elementary mistake.  please forgive me if this seems like a condescending question. 

best wishes, gm

[Tamir]

ok, now the jacks wires are soldered good accordding to your explanation.
still the same.
I moved the MM to the beeps mode and when I connect its wires it beeps. when I attach the black to the ground and the red to the 9+ on the circuit I don't get a sound.

Yes I soldered the right side
sorry for my bad english, it is not my native language.

[gaussmarkov]

ok, now the jacks wires are soldered good accordding to your explanation.
still the same.

so the rings of both jacks are connected to the ground strip?  and if you use your continuity check to see whether one ring is connected to the other, you get a beep? 

I moved the MM to the beeps mode and when I connect its wires it beeps. when I attach the black to the ground and the red to the 9+ on the circuit I don't get a sound.

hmm.  so if you have the battery connected, do you also read 0V across the battery posts as well as across the bottom and top strips?  and if you have the battery disconnected, you get about 9V?  that would not be consistent with finding no short between the two strips, unless that battery wasn't really connected even though it seemed to be. 

how are you hooking up the battery?  are you using a battery snap with the wires soldered to the strips (black to ground, red to +9V)?

[Tamir]

That's how everything is wired (without the POT)

[petemoore]

  Clip the black DMM lead to ground, set for beep mode.
  Test every ground in your circuit shown on the schematic [including at least both jack sleeves, circuit ground, and battery clip small side, you should hear beeps for all gnd points from ground.
  test that you Don't hear a beep across the circuit battery clip [V+/V-] stop if you do...
  Then clip the black lead to the battery clip + [large side], follow the red wire to the V+ rail of the circuit [Above Drain bias resistor], you should have continuity between the bat clip and where it's shown to connect on teh schematic.
  Then clip on a good battery, test right at the battery for voltage...because you verified the battery connection [^] you should be seeing the battery voltage represented on the V+/V- points on the board, across where the clip connections go.
  These things should help at least to get a[verified non-shorting] battery connected to the circuit board.