Noisy Cricket isn't very Noisy (Debug)

[wildebelor]

So I'm having some trouble with this and I can't see why?
I used the GGG wiring diagram for non-true bypass + LED


And I'm getting signal.... just not when the amp is on?
 

1. When in bypass, signal comes through (no controls work however e.g. pots do nothing). When powered on, led comes on, no signal.
2.Name of the circuit = Noisy Cricket
3.Source of the circuit (URL of schematic or project) =
4.Any modifications to the circuit? N
5.Any parts substitutions? N
6.Positive ground to negative ground conversion? N
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? => 8.96
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 = 8.94
Voltage at the circuit board end of the black battery lead = 0.00

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:


IC1
P1 1.32
P2 0.01
P3 0.00
P4 0.00

P5 4.15
P6 8.92
P7 4.46
P8 1.32


Thanks in advance!

[Jdansti]

I think you're making this harder than it has to be.  The Noisy Cricket is an amp, not an effect. There's no need to bypass it. What do you have connected to the output?  It should be a speaker. As for switches, you just need an on/off switch. You actually don't even need that, you could just unplug it to turn it off.

[wildebelor]

I think you're making this harder than it has to be.  The Noisy Cricket is an amp, not an effect. There's no need to bypass it. What do you have connected to the output?  It should be a speaker. As for switches, you just need an on/off switch. You actually don't even need that, you could just unplug it to turn it off.

HAHAHA ofcourse! Too many wires today has sent me backwards!
Connected to the output is a jack which allows for any speaker via 1/4" jack.
All I was attempting to do was create an on off switch and overcomplicated it!

Would you mind pointing me in the right direction?

[Jdansti]

Here's all you need to do. Just put a SPST switch between your power supply (or battery) and the 9v in on the board.



Edit: BTW, the board already has a resistor for the LED, so just connect the + side of the LED to the spot labeled LED, and connect the negative side of the LED to ground.

[wildebelor]

and -LED goes to ground?

[wildebelor]

wired it up as suggested and the LED comes on but still no sound?
Now I don't have any sound when bypassed because of the new switch wiring.

[Jdansti]

There is no bypass. Just on/off. When it's off, you should not get any sound. Just like any other amp. Do you have another amp, or have you played through another amp?  You get no sound until you turn it on.

Your input jack tip should be connected directly to the pad labeled "Input" on your board. Your output jack tip should be connected directly to the pad labeled "Output" on the board. The jack sleeves should be connected to the board ground. You should not have any other switches* other than the on/off switch for the power. Connect everything to the board as shown in the Noisy Cricket drawing. Disconnect everything else. Pretend as if you never saw the bypass drawing. It has nothing to do with making an amp work. Forget you ever heard the word bypass and utter it (type it) no more until you build your next stompbox!

Edit: *correction- you still have the bass and grit switches.

[wildebelor]

There is no bypass. Just on/off. When it's off, you should not get any sound. Just like any other amp. Do you have another amp, or have you played through another amp?  You get no sound until you turn it on.

Your input jack tip should be connected directly to the pad labeled "Input" on your board. Your output jack tip should be connected directly to the pad labeled "Output" on the board. The jack sleeves should be connected to the board ground. You should not have any other switches* other than the on/off switch for the power. Connect everything to the board as shown in the Noisy Cricket drawing. Disconnect everything else. Pretend as if you never saw the bypass drawing. It has nothing to do with making an amp work. Forget you ever heard the word bypass and utter it (type it) no more until you build your next stompbox!

Edit: *correction- you still have the bass and grit switches.

Forgive me, I shouldn't have used the word bypass - it's been a long day!
Yes I own several amps haha
I have literally wired it exactly as you have described and still, I have no sound.

[Jdansti]

I thought you might have played through an amp before!

Can you post some clear pics of both sides of the board and show the off-board wiring?

[wildebelor]

The bottom of the board looked a lot nicer before I reflowed some joints and made sure there weren't any bridges with a xacto knife! 

[pappasmurfsharem]

It doesn't appear that you used sockets. So this might be difficult. I didn't use this vero layout but depending on what FET you used you might need to flip it around.

[Kipper4]

Does it work outside the box?

[Jdansti]

I'm traveling right now, but I'll take a closer look tonight. One thing that comes to mind when I saw your battery clip is to make sure you have 9V when the amp is on. This amp will go through batteries fast. It's better to have an plug-in adapter with 9 or 12 VDC output.

[wildebelor]

So the jfet I used is a MPF102 as per the layout.  definitely not in backwards haha
My battery (when amp is on) reads 8.9volts - the only reason I didn't want to have a power supply plug is because I wanted this thing to be portable and play it anywhere etc.
It's got to be another reason - could the chip be bad?

[pappasmurfsharem]

So the jfet I used is a MPF102 as per the layout.  definitely not in backwards haha
My battery (when amp is on) reads 8.9volts - the only reason I didn't want to have a power supply plug is because I wanted this thing to be portable and play it anywhere etc.
It's got to be another reason - could the chip be bad?

I'm just saying when I built it on breadboard my pin out should have been correct. But flipping it worked, not saying it your issue of course but you never know assuming all things are created equal your pin out and the layouts pin out match the Fairchild data sheet.

It is possible that it may have been damaged in the soldering process, that's why you'll see many of us using sockets.

[wildebelor]

I unfortunately ran out of sockets, figured this little build wouldn't be a problem so boycotted the sockets!
BOY WAS I WRONG.

What's the best way to check the jfet for damage?

[Jdansti]

I'll let someone who knows more than I do answer the JFET question.

The battery is OK for now.

I don't see anything obvious. Yes it's possible that the chip is bad, but it's not very likely.

The solder joints on the pots are very close to the metal pot cases. Make sure that the wires and solder are not touching the pot cases.

Even though you've scraped between traces, you might want to check the continuity between adjacent traces. Be sure to check on both sides of cuts. Keep in mind that you might read the resistance of a component while doing this check.

Also, it's difficult to check from the photos, but you should check that each components' leads land in the correct holes on the Vero board.

If none of this helps, you might want to make a quickie audio probe as shown here: http://www.diystompboxes.com/pedals/debug.html

[duck_arse]

+1 on the pot wires.

you need to introduce some variety to your wiring colour scheme.

[wildebelor]

-1 on the pot / wire situation haha

Nothing is or was touching!
And everything seems to be in accordance, time to make an audio probe!
Will report back shortly

[wildebelor]

audio probe didn't seem to come up with anything, I'm going to get a new jfet and see if that changes anything. otherwise I'm absolutely stumped.