[Barry]

5,000 at a glance.

[Barry]

That is a good thing to try after I get some more info on his build.

I am getting all this new information at the same time.

This circuit will be featured in an upcoming DC movie and the guy that built it up for his studio did this:

 

His final comments are:

3k9 becomes 100 K

Gain P1 becomes 300k ( with cross parallel resistor)

Leg 1 has 8.2k resistor before going back to pcb

Awesome sound

 

This is his rig for the DC movie (release date is July 29, 2022) which includes all GuitarPCB projects.

 

 

[Barry]

You will need to post clear photos. You need to verify every component again and reheat every solder joint to re-flow the solder. We have a printable resistor card on the Guides Page if that helps quicken the verification.

[Barry]

Yes I meant 5:00 as full up and yes it is fun IMHO.

So I am confused a bit here. You are saying that there is no difference between the Wiring Diagram Mod I made above and just attaching a B1M pot stock? Details on that specific change between stock and my mod as shown in the diagram is what I need to know. Details on the Pot value only needed to be close to verify the 1M worked correctly, nothing more. It appears good to me.

If there is no change or very little change between my Mod and Stock (I would have expected a real change) then take the 3k9 value on the board and drop it to 100R or something close to that. After doing that Bias the circuit again to 5v. or do I mean 4v (kidding).

After doing that update me on the change regarding just dropping that value while still utilizing my Pot mod.

@Billy: more heads are always better than one. I think you get what I am going for here. Build everything stock except for R11 (make that near 3k9) and make the Gain Pot (B500K). After testing that try adding a 1M resistor to the Gain Pot. What are the results? If needed further reduce the value of R11 to 100R. Results?

[Barry]

Yup that is kind of important. Thanks for pointing that out.

[Barry]

Yah can’t stop this process when we are nearly finished and about to have a major breakthrough 🙂

This could also be some of the best stuff you learn this year. So if you will indulge me…

I need you to answer 2 questions:

1. Did you confirm by putting a DMM set to Ω on lugs 1 & 3 with the Gain pot turned up full using a 1M resistor in parallel across lugs 1 & 3 that it indeed measures near 330K or .330M.
2. I would like to confirm what you mean by 7 and 8 o’clock. To me 7:00 would be the furthest counter clockwise you can go. 8 o’clock would just be a pinch of a turn more than that. 4:00 would represent Full Up.

Update Note: When testing the POT value, the pot must not be connected to the board. If you know you have this wired correctly based on the image below then you can skip the testing step and proceed if you wish.

Mod Finalized:

To expand on the Gain Pot Mod simply add-on another resistor this time in series with Lug 1 going to the main board Pad 1 (note board silkscreen 1) anything from 8.2k to 10k should do nicely.

Make sure you are doing this mod to a B500K pot and not a 1M Pot. The numbers would all be wrong otherwise.

Here is a nice image I made up for this.

 

Final thoughts and questions:

I will assume you have been testing with a high gain humbucker pickup?

Test with same pickup and see what you notice. Any changes?

 

Test with a single coil pickup. What happens?

You can use the clock analogy to answer as long as 7:00 is full counter clockwise and 4:00 is Full Up.

One Last Mod: Drop that 3k9 value down to 100 Ohms or any Ohm value you have near that. Thoughts?

Thanks again for testing this out for me and responding with your findings. The answers will be important to a 2021 revision.

[Barry]

Yah Wing Commander was an awesome game especially for the time. That even preceded Starcraft by almost a decade.

[Barry]

You can do another pedal mate to be the Firekkan.

Well done and thanks for sharing.

[Barry]

I believe that is the case for the voltage issue. Noted and upgrading.

I would Bias at half the supply voltage and only go up from there as needed.

Now for the 2nd problem.

Try lightly tacking on a 1M resistor connecting lugs 1 and 3 of your B500k Gain potentiometer. I say lightly tack because you can try other values using a Parallel Resistance Calculator. That should give you a value of about 330K (test with your DMM). Let me know how that works out for the Gain range. Keeping in mind this is a high gain circuit as well as a circuit to suit different types of pickups.

[Barry]

I just checked one of my boards. There is no continuity between the two pads on mine. That is a board error. The solution would be to remove the +9v wire from the right pad and place it on the left pad.

Thanks for pointing that out so this gets fixed for a 2021 board.

[Barry]

If the EM does not invert the phase then place it in the loop of the Buff N’ Blend as is.

Place a Stage 3 Booster in series in the same enclosure after the EM/Buff N Blend.

No need to worry about the Stage 3 changing the phase because it is not in the loop. No need to worry about 2 buffers either.

That is about it.

[Barry]

Hi Robert,

Do me a favor and replace only R11 with anything from 3.3k to 4.7k

Let me know how that works please.

Barry

[Barry]

Awesome Possum.

[Barry]

MPF102, J201, 2N5457.

I might use a socket to be able to switch out the transistor in case you have trouble with Biasing.

I carry them all in my shop if needed including the J113. They all have the same orientation for pinout as well.

[Barry]

Hi Alan,

I contacted Klaus for you.

I would give him a day or two to respond. I am sure he will take care of you.

[Barry]

So no more guesses or thoughts?

I am not going to pull teeth here, lol.

[Barry]

The Mini-Me 2021 schematic looks like this.

Klaus should be contacting you soon about this.

Every time I look at the Mini-Me schematic I say in French: Jai tant reve du toi. 🙂

[Author]

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