Help with LED install on madbean rangemaster

[joshcamp]

Hello Im new here and also new to madbean pedals.  I recently built the rangemaster effect and it sounds amazing !

I am trying to add an LED using the wiring diagram for 3pdt switch and circuit baord from small bear elect.
The circuit is found at small bear's website: http://www.smallbearelec.com/Detail.bok?no=870
sorry -i havent figured out how to post its picture here...

The problem is that when the effect is swtiched on, the led is bright for less than a second and then goes very dim to not visible at all.   I cant seem to figure this one out..  need help

[madbean]

Josh,

Is your Rangemaster positive ground? Is so, you need to reverse the LED.

[jkokura]

It sounds like you've burnt out your LED also. You need to replace it, and as Brian said, reverse it from the way you had it last time.

Do you have a resistor in series with the LED also?

Jacob

[joshcamp]

It is PNP.

I will try reversing the led and also use a new LED.   Thanks guys !

Also, I am using a battery for this but would really like to use a power supply.  Is it possible to use a power supply on this ?

[jkokura]

You can use a power supply as long as it supplies tip positive power. That means a typical boss power supply will not work with this for a power supply.

If you have a typical power box like the Pedal Power Plus or Supacharger, you can use a 2.1mm tip positive adapter like the one available from VooDoo Labs. The barrel colour is white, and it's about 4 or 5 bucks to buy one. If you use a One Spot or other wall wart power supply, I believe there are One Spot adapters available that will reverse the polarity for you, look for them.

Jacob

[madbean]

Let me put in a plug for the new Road Rage board that will be out in about a week. You can pull 18v, -9v and either 12v or 15v regulated off of one board when using a standard 2.1mm 9v PS. Total cost to build it (including board) will be about the same as buying one of the positive tip cables. So, you can use it to supply higher voltages to pedals like the original RR, but also use it to power positive ground effects with the regular 9v plug.

[CRBMoA]

Actually, the circuit is negative ground, but the DC jack is just a DC jack. Unless you are doing something special with it, neither ring nor sleeve come in contact with the enclosure, and you could simply wire it opposite of conventional (i.e. 9+ to ground and and 9- to the power lead for the board).

Unless I am missing something obvious to the rest of the class, this should work.

[madbean]

Actually, the circuit is negative ground, but the DC jack is just a DC jack. Unless you are doing something special with it, neither ring nor sleeve come in contact with the enclosure, and you could simply wire it opposite of conventional (i.e. 9+ to ground and and 9- to the power lead for the board).

Unless I am missing something obvious to the rest of the class, this should work.

Don't do this! You will fry your power supply and your transistor most likely. The circuit is positive ground. If you were to just swap the neg/pos on the DC jack and plugged it into a PS that is not isolated you are going to kill it all.

The reason you can supply positive ground with the VLPP is that each output is isolated from the other. Therefore, by switching the lead and ground at the cable you can safely supply -9v to your positive ground effect. But not all power supplies are isolated like this. I have one that is not, as well as the VLPP.

[CRBMoA]

I guess that's why you are an Electron Doctor and I am a Diode Destroyer.

I build my own P/Ss, and they are all isolated, and I don't have any positive ground circuits on my board at the moment.

Getting spanked twice in one afternoon is enough. I'll go back to lurking for a few days.

[madbean]

Ah, man, please don't take it personally! Believe me, I made the same mistake myself a few years ago. It's all a learning process.

[CRBMoA]

Dude. I am a bass player. We don't have feelings, and we break things. That how we learn.

You have taught me a lot that past couple of years. You have taken the time to answer my PMs on several boards, not just this one.

Heck, you sold me my bestest new soldering station, and the Darkside project you made launched my custom order business. I currently have 7 orders on the bench or coming to me, and I never would have gotten where I am without that board. 

I don't mind being the poster child. I'll just change my sig to something like,

"The views expressed in the above post do not necessarily reflect the opinions of Mr. Bean or his organization. If you blow shit up because you listened to a bass player, you are on your own."

[madbean]

LOL....so is this a good time to mention I played bass "semi-professionally" for 3 years? Maybe not 

[joshcamp]

thanks for the help guys - it works now !

btw, what is the road rage ?   I see it listed on your projects page in the 'other' section but i dont know what it does ....

[madbean]

Ver.1 was a straight charge pump. 9v in and about 18v out. Ver 2 is as I described above.