[brd]

tip #4 use sockets for all IC’s and transistors.

I don’t know of any way to test the IC’s until it’s finished.

I think I would wait and see There is a chance they have been damaged by the heat already, but de-soldering them will just increase that chance plus you risk damaging the pads on the board. The only difficult point I can see is the pads for the large IC will be under the Volume pot when it’s finished. On the other hand if you already have replacements it could be easier to do it now. Tough call.

Maybe wait for another opinion.

[brd]

Vokinn72

Welcome to the exciting journey that is pedal building. I’m not one of the gurus here but I try to help where I can. As for your question about the diodes. the build doc has a picture of the board that I’m using for reference. there are only 2 diodes in the build. D1 is an LED, D2 is a 1N5817. The printing on the board sometimes has a circle with a flat spot to help orientate an LED, this one just has a plus and minus sign. here is a picture to help you.

  The LED has a flat spot. The positive side is the Anode, the negative side is the Cathode.

D2 should be installed as shown in the build doc in the upper right corner.  The cathode should be to the right.

As far as tips to get started.

1. First read the beginners guides Barry mentioned.
2. Read the build doc. There are usually build notes for important information.
3. get good at soldering. Use a small pointed tip, and get the temp right so you can get a good solder as quickly as possible. With my rig 7 seconds is about all it takes.3 second to warm up 1 second to melt the solder and 3 second to be sure it flows around the pad. Barry’s boards are pretty robust but you can still damage any board by getting the pad too hot.

Other tips

• start with the components that lay the closest to the board and work your way up. resistors first, then diodes. then usually sockets and small MLCC caps then the box caps and electrolytic’s last. I use a small piece of electrical tape sometimes to hold components in place.
• Get good at de-soldering. I don’t like using the braids. I use a pump that looks like a large pen that has a plunger and a button to trigger the suction.
• take your time soldering switches and pots, give a good 30 seconds at least, between soldering the leads to avoid overheating the guts.

I hope that helps

 

[brd]

If you are looking to modify the mid scoop, my suggestion for the least extra components is to use the following values in the tone stack

C10 3n3

C11 10n

R18 39K

R20 39K

Then you can use a DPDT on-off-on switch with 2 caps as  shown below to get a mid scoop, flat response or mid boost.

This is borrowed from tagboardeffects for a Hizumitas work alike

You can plug the values into the BMP tone stack calculator on TSC in the web to see the effects. The caps will parallel C10 so you will have effective values of 3.3nf, 8nf and 13.3nf for C10

I hope that helps

[brd]

Here is a pinout for a metal can type 2N2222. The leg closest to the tag should go to the E pad on the board if using this type.

It’s handy to have a component tester to identify component leads.  ( I use an Atlas DCA55 ) it can save time instead of searching for datasheets. Hope that helps.

[brd]

Put the wires from the 4 pin connector where ever they were when you posted that the boost switch made the volume, tone and overdrive work. That is now your on/off switch.  If you have the other switch properly orientated then you should be able to swap the yellow and black wire on the stomp switch that the 3 pin connector goes to and all should be working fine. If you already have the switches labeled on the front graphics, just swap (move) the stomp switches, it looks like you have enough wire. I hope that helps.

[brd]

I might be able to simplify if further. your boost is switched on and off by making a connection between either the yellow and red  or yellow and black wires from the 3 pin connector. you can try to manually connect them to verify the boost is switching on and off and working as expected. If that’s good, then wire the stomp switch accordingly. yellow on a middle pole and red and black on the corresponding throws. use an ohm meter to verify you have it oriented correctly.

[brd]

Sorry I didn’t think of it earlier, you could also try connecting the wet and dry sends to the amp. If you get sound, the problem is in the last half of the circuit then. Also be sure the Volume pots are  fully clockwise when using the normal output jack, those are more like blend controls.

The box looks awesome BTW. I have one of my paramix’s in the same enclosure.

[brd]

Johnnysmoke,

My first check whenever a pedal doesn’t make any noise, is the input and output cables, go direct guitar to amp through both cables. That verifies the guitar and cables and amp.

Try plugging the guitar into the returns then, If you get sound, then your problem is in the front half of the circuit.

Then check voltage (DC) on the board, at the 9v+ pad and a ground. if that is good then verify the bias voltage (VB) that would be at pins 3, 5, and 10 on the IC, that should usually be around half the supply voltage, 4.5 volts. while your there write down the voltage readings for the other pins. pin 4 should be 9v. pin 11 should be 0v. NOTE: the pin to the left of the dot on the IC is 1 and you count down and over then back up..

If nothing obvious is wrong ,at this pint I would break out the audio probe. I’m not one of the guru’s here.This is where they take over.

Remember those folks that build their pedals all neat and tidy, are artists, I’m not one of them, It doesn’t matter what it looks like, as long as it works..Post some pictures and the voltage measurements..

[brd]

I ran out to my shop and grabbed my box of IC’s and my notes to see if I had any LM-1458’s, but sadly I have none in stock here.

Swapping IC’s is a very easy mod, I highly recommend trying it. The hardest part is not bending the legs prying them out of a socket. ( no I don’t have the tool )

I used all OPA-2134’s in my last Mule Kicker build, IMO the best sounding Klon I’ve built yet.

Have a look at this link http://www.geofex.com/article_folders/potsecrets/potscret.htm ,  I hope Barry doesn’t mind me posting that here. It’s a lot of information, but the section on pot tapers is helpful and also describes how to make your own custom tapers if you ever need that.

I think Bruce Lee once said “whatever works use it”. ( or something like that). So yeah, that’s the beauty of it, we can make them any way we want.

Best

BRD

[brd]

The traces are the lines in the schematic connecting the components, they can be signal or power.  They run traces on both sides because they can’t cross. They are not drawn like the schematic because that would waste space on the board. Hope that helps.

[brd]

Sounds like what happens when you connect the power supply to an active pedal. You will get a pop and a delay before signal is passed. Check voltage on the board with the switch in bypass.

[brd]

Go bright and crank up the fog machine, you’ll get a stage light show off of your pedal board. Best reason to use the bi-color led’s

[brd]

Well done Barry, this forum sets GuitarPCB above the rest. Thank you for making it possible.

[brd]

Using the schematic and the readings that you have already supplied I think your Va, Vb, and Vc reading are fine.

Long explanation:

Va should be the same as your Q1 drain voltage, which was 7.4v. The expected value given by Barry was 7.27v. That is close enough.

Vb should be half of Va because of the voltage divider R29 and R30, which it is.

Vc should equal to your collector voltage on Q2 and Q3, which it is, and it is close enough to the expected voltage of 5.05v

What doesn’t look correct is your base voltage (middle pin) on Q2. Barry’s number is 3.75v you are at 1.48v.

Recheck that voltage measurement and be sure you have the Decay pot turned fully counter clockwise.

Also, Just using a little math, you have a diode D3 that should be dropping at least .25v so you should expect your voltage at pin 1 of IC2 to be at least .25v higher than your base voltage on Q2. Your readings are nearly identical, that doesn’t seem correct either.

Just to be sure, Are Q2 and Q3 BC550’s?

[brd]

Nice build, and thanks for the post Steve.

[brd]

There is a small pass through next to R23, that is suspiciously close to pin 1 of IC2. Check your work there to see if you may have bridged that by accident.

[brd]

Thanks for the tip, I wish I had that information a few years ago. However, talent and patience are the missing ingredients here. Below is a photo of my first and last pedals, clearly showing no improvement in my art or my ADHD.

[Author]

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