adding a 9v adapter and LED to a rangemaster

[wsaraceni]

I have a rangemaster clone im trying to build.  it's my first pedal.   I don't really have room for a 9v battery inside so I want to use my kingtone battery box.   I built the pedal with a on a 6 turret strip and have it all wired up.  im using a brown bear electronics pre-biased OC44 (CV7003) and their kit for the rangemaster build but I want to add a LED and 9v adapter.   are there any layouts floating around?  a search left me still looking.   im sure it's a simple thing to do but I haven't figured it out yet. 

[idy]

Welcome to the forum.

OC44 is a PNP transistor, which means, like a stock Rangemaster, your will be "positive ground." This circuit will not daisy chain with other normal negative ground effects... without some kind of workaround. These include:

Using a separate power supply for it (and any other + ground circuits you have)

Using a charge pump to turn your 9v into -9v. Many effects PCB guys add these to PNP circuits. https://guitarpcb.com/product/pumpd-up-rangemaster-plus/

Redesign for Negative ground. Works in theory, in real life is unstable....

[wsaraceni]

i want to keep it reverse polarity.  i'm fine with the requirements using an isolated reverse polarity cable.  I'll actually still be using it with a battery, ill just be using the kingtone battery box.   it's isolated and i can use 4 pedals with it.   

im just unsure as to how to wire the 3pdt switch, DC jack,  and LED/resistor with the original rangemaster design. 

all my negative center pedals will run off of a standard voodoo labs power supply (2 plus)

[idy]

http://www.griffineffects.com/content/29-wire-a-true-bypass-switch-with-led-positive-ground

I googled "positive ground bypass switching."

The diagram looks right.

[wsaraceni]

that worked.  the design I was using had the same layout with the exception of the middle row of the switch and the left row were swapped but that doesn't matter from what I can tell.

it sounds good.  I haven't tried using the DC jack but the pedal works so that's a success.  I just have to find if the knob is supposed to go from full blown sound to muted.  with the knob fully counter clockwise there is no sound.  it's almost like using the volume knob on the guitar just with more high end.  I kind of like it.   

[MikeA]

Right, the knob on a Rangemaster is like the volume knob on a guitar, it's at the output of the circuit and goes from zero volume counterclockwise to full volume clockwise.   And that's what the Rangemaster does, selectively boosting the treble more than the mids and bass.

[wsaraceni]

well the battery works but the power adapter doesn't.  im using a reverse polarity cable but no power when It's plugged into the kingtone power adapter.   time for some more troubleshooting.   

[idy]

If you used the Griffin diagram in the link, you don't need a reverse polarity cable. The big tab on the DC jack goes to center...negative...

[wsaraceni]

thanks. I realized that partway through and swapped that out.   I guess most pedals that do require a reverse polarity just wire the jack up the standard way and then only reverse the battery leads?   seems like a weird way to do it.   I have to sound test it now but I think I have it fixed.  I was using the wrong power cable briefly and I also had the input jack sleeve and ring wired backwards.   

I hope I didn't fry the transistor, although I have one spare.