Onboard Rangemaster + biasing questions

[dudiluty]

Hi there.

I build a oc44 rangemaster on a mini tagboard that i want to install in my strat. I would like to be able to use a dpdt toggle switch to turn it on and off. How do i exactly wire this into my strat ?

Another questioquestie bias of the rangemaster is nog 4.78v at the Collector and Emitters, the Base is 5.04v. How do i exaclty change the bias to 7v without using pots ? Change the value of the 68k resistor ?

Thanks

[dudiluty]

Should this work ?? I like to be able to turn the effect on and off with the switch.

[jeremy]

dont have the schematic but maybe you can see what ya need on mine. oh, and heres the front just cause its awesome.

[jeremy]

[Mincer]

^Wow! That is supremely cool.

[jeremy]

a buddy is a union electrician and was replacing the old fire alarms so he took a bunch home since they were just going in the trash anyway, and we figured out how to make them into pedals. he has one and i have one. you can see how little there is in even a modified rangemaster

[Securb]

That is cool as hell

[dudiluty]

dont have the schematic but maybe you can see what ya need on mine. oh, and heres the front just cause its awesome.

Thanks. But i did build a lot of rangemasters already. I'm just not sure how to wire it as a onboard effect in a strat with a toggle switch and on the volume pot.

[ErikH]

That is very cool.

As for wiring it in a guitar, I wouldn't. That's must me. I see problems with interference and if the component leads aren't insulated, that could lead to it grounding out or worse. Those transistors don't like seeing wrong polarity.

Another option would be to wire it so that it can be attached to your guitar strap. That way you can use it with any guitar. Just my 2 cents.

As for the bias, that should be biased. Normally it's half of the supply voltage, which is 9V so the bias should be around 4.5V. I'd have to dig up my notes on biasing the transistor. It's been years since I made my RM clone.

[dudiluty]

That is very cool.

As for wiring it in a guitar, I wouldn't. That's must me. I see problems with interference and if the component leads aren't insulated, that could lead to it grounding out or worse. Those transistors don't like seeing wrong polarity.

Another option would be to wire it so that it can be attached to your guitar strap. That way you can use it with any guitar. Just my 2 cents.

As for the bias, that should be biased. Normally it's half of the supply voltage, which is 9V so the bias should be around 4.5V. I'd have to dig up my notes on biasing the transistor. It's been years since I made my RM clone.

I know but i make my rangemaster clones center negative. So people can use them in daisy chain and with standard 9v adapters. If it's not a good idea to put a transistor in a guitar(maybe signal noise from pickups) i wont do it.

[dudiluty]

That is very cool.

As for wiring it in a guitar, I wouldn't. That's must me. I see problems with interference and if the component leads aren't insulated, that could lead to it grounding out or worse. Those transistors don't like seeing wrong polarity.

Another option would be to wire it so that it can be attached to your guitar strap. That way you can use it with any guitar. Just my 2 cents.

As for the bias, that should be biased. Normally it's half of the supply voltage, which is 9V so the bias should be around 4.5V. I'd have to dig up my notes on biasing the transistor. It's been years since I made my RM clone.

I know but i make my rangemaster clones center negative. So people can use them in daisy chain and with standard 9v adapters. If it's not a good idea to put a transistor in a guitar(maybe signal noise from pickups) i wont do it.

[dudiluty]

I just measured the bias again after it has sit down for a while.

I measure this:
e 7.33v
B 7.63v
C 7.34v

[ErikH]

I just measured the bias again after it has sit down for a while.

I measure this:
e 7.33v
B 7.63v
C 7.34v

Yeah, that's not right.

Read this if you haven't already. Great info and worth downloading to keep handy.

http://www.geofex.com/article_folders/rangemaster/atboost.pdf

[dudiluty]

Yeah, that's not right.

Read this if you haven't already. Great info and worth downloading to keep handy.
http://www.geofex.com/article_folder...er/atboost.pdf

Thanks that's helpful. So i have to increase 68k resistor to get to 7v.