Another pedal another problem

[Guybrush]

Hey all

True to form I've just finished another pedal and it doesn't work. It's my second attempt at a Doombutter. Sound in bypass but nothing when the pedal is engaged. The internal LED doesn't light and the transistor/regulator is getting really hot.

I've been through it multiple times and can't find the problem/s. Without wanting to sound like I'm having a tantrum, I'm seriously thinking about hanging up my soldering iron for good this time. I don't think I've got the skills for this.
Is there anyone out there with greater debugging skills than me that would be kind enough to have a look at it for me? I'll post it out to you and obviously cover the return postage and buy you a pint. I'd be extremely grateful and you might just stop me throwing my parts box out of the window!

Pictures:






Thanks

Martin.

[Govmnt_Lacky]

Martin,

Right off the bat I see a few items of interest.

1) Right where your power wire (red one i assume) is soldered onto the PCB. Looks like the solder joint is suspect. Same goes for the larger cap in the upper right hand side of the component-side pic. Looks like a bad joint.

2) Right next to the "Ver 1", there appears to be a solder bridge. Could be wrong though as it looks like it is a power filter cap connected to the power rail.

Have you gone through the circuit and looked for solder bridges annd verified component values?

Voltages might help as well 

[lincolnic]

Don't give up! Like most things worth doing, it takes some practice. You'll get better at it, and you'll feel awesome.

[jimilee]

Absolutely don't quit. I've been thinking about this post the better part of the day.you didn't learn to play guitar over night,it just takes patience and practice. You've chosen an etched board for number 2, and those are no easy task. Be patient and well talk you down.

[Stomptown]

In addition to advice above look and see if there is a possible bridge where your input wire is soldered (green wire) and at C2 as well. This is not an easy project if you are just beginning so don't be discouraged. Etched boards are not easy at all. My first attempt was a phase 90. FAIL. Then I tried a TS-808. FAIL!!! I was pretty discouraged myself, but I shifted gears and started working with fabbed PCB's and basically honed my soldering skills. I eventually tried etching again and started with a simple fuzz. It worked! I'm still no pro, but I have done a few complicated etched boards with no problem. Some people have no problem jumping in the deep end but if we can't help you get this one running I would consider an easier etch (i.e. boost/fuzz/low parts count overdrive) or a fabbed board. Don't give up! You deserve to have the feeling of firing up your own build...

[billstein]

These etched boards that have such tight ground planes are a challenge to begin with. You might want to try a layout from www.generalguitargadgets.com. His designs usually have more room between traces. You can build up you're soldering skills and get a few successful builds.

If you like compressors his Orange Squeezer is a nice easy one pot build and is a great sounding pedal.

http://www.generalguitargadgets.com/pdf/ggg_osq_lo_pot.pdf?phpMyAdmin=4a28f86a515b7883e7bc35a68d4e7b6d&phpMyAdmin=78482479fd7e7fc3768044a841b3e85a

Like the others have said, don't give up you have a whole community here that will help you. It is a fantastic feeling to look down and see pedals you have built yourself.

[Guybrush]

Hi guys

Thank you for all the advice and encouragement. I'm sure you've all had moments where you feel like packing it in! Ha.

I've checked all the joints and there doesn't seem to be any bridges. A pad has lifted slightly C12 but I've checked with my dmm and there's continuity between the leg of the cap and the connecting leg of the IC socket so I don't think that's the issue.

I checked all the component values and they all seem spot on. The Wima box cap at C4 is marked 0.01. That is 10nf isn't it?

I plugged it in again this morning (I'm in the uk) and the transistor/regulator instantly started smoking. This happened with my last attempt too. Could I have a dodgy batch or is this more likely to be a sign of a problem elsewhere in the circuit?

Thanks  again for the help. It's really appreciated.

Martin.

[Thomas_H]

Hi, as you are saying that the regulator immediately started smoking- can you remove it and use your DMM to find out if there is a shortcut between Pin 1 and 3 or 4 of the PT 2399? (Remove ic and meassure resistance at the socket)
If the reading is 0 Ohm then you can make the next step and check the IC socket pins for bridges or remove C8
To check again.

EDIT: i just digged the build doc and the only way you can have that trouble is right where the regulator is soldered (you might want to reheat the three pins and see it they flow apart or stick togeteher) and with C8.

It only goes step by step Im afraid.

[Guybrush]

So in brief I need to remove the regulator, re-solder the socket and C8? I'll give it a shot after work.

Thanks again!

[Thomas_H]

yes, just go step by step.

remove regulator
meassure resistance (to see if there is a shortcut)
if shortcut then reheat regulator socket pins or desolder socket.
if there s still a shortcut remove C8, meassure again.

depending on the outcome next steps vary.

[RobA]

Check the pinout and orientation on your voltage regulator. I think it may be in backwards.

Edit:
If it is in backwards, it's likely dead now. So, you should try another. The pinouts for very similar regulators can be different, so you need to check the spec sheet for your particular model.

[Effectsiation]

Check the pinout and orientation on your voltage regulator. I think it may be in backwards.

Edit:
If it is in backwards, it's likely dead now. So, you should try another. The pinouts for very similar regulators can be different, so you need to check the spec sheet for your particular model.

What he said, Voltage Regulator is backwards.

[Guybrush]

I REALLY hope that this is the problem. I bought them off eBay and tey doidn't come with a spec sheet so I can't check. I'll just have to stick one in back to front and see if it works.

Thanks

EDIT: These are the regulators I bought http://www.ebay.co.uk/itm/REG-LM78L05ACZ-5-0V-100mA-TO-92-3-IC-VOLTAGE-REGULATOR-NATIONAL-/190816232397?ssPageName=ADME:X:AAQ:GB:1123

[Govmnt_Lacky]

It looks to me like you have the regulator in correctly according to your pic (based on the datasheet).

[TreeSlayer]

Check the pinout and orientation on your voltage regulator. I think it may be in backwards.

Edit:
If it is in backwards, it's likely dead now. So, you should try another. The pinouts for very similar regulators can be different, so you need to check the spec sheet for your particular model.

What he said, Voltage Regulator is backwards.

+2 if you are using LM78L05 in IC3, it's backward...