Road Rage wiring

[lincolnic]

So I'm about to build two of the PAiA ring mod kits (one for me, one for one of the studios where I work), and they need bipolar power supplies. Perfect opportunity to use the new Road Rage boards...except I have no idea how to wire them up. Can anyone help me out? For what it's worth, I'll be building them into the same enclosures as the ring mods.

Also, what exactly do I need for the regulator? I get a few results when I search for "regulator" on Small Bear, but I'm not sure which to get.

[madbean]

Can you provide a little more info on the kit...a link? Let me make sure I understand what is required before going further. If it only requires +/-9v, then you don't need a regulator. The regulator was included simply as a convenience to cover multiple power requirements. But, typically a regulator will be named similar to 78L05, 78L12 (5v and 12v resp) and so on. Regulators are also usually classified under integrated circuits, even though they are in transistor packaging.

[lincolnic]

Sorry Brian, the PAiA site doesn't have any info (the kit doesn't even include a wiring diagram, but I was able to figure that much out on my own). If you happen to have a copy of Electronics Projects for Musicians handy, it's the same ring mod that's in there.

What I can tell you is that the effect requires a bipolar power supply - there are pads on the PCB for negative and positive voltages. It was originally designed to run on two 9-volts, but that seems wasteful to me, so I want to use the Road Rage as a bipolar supply.

I know I don't need the regulator, but I wasn't sure if the board would still function properly without one. Can I just leave that off, then? All I need, in a nutshell, is +9v and -9v, which I know this can give me, but I'm not sure how to hook it up (vis-a-vis the AC adaptor and/or battery clip) to make that happen.

[madbean]

Okay, gotcha.

The regulator can be left off. The RR will supply all the possible voltages simultaneously, BTW.

So, bring your DC jack 9v wire into the 9v input of the Road Rage. There, it will be filtered and reverse-polarity protected. You can simply take another wire out from the adjacent +9v pad to your board. Then, wire both the -9v and ground from the RR to the appropriate pads on your main board. Since you are only using the +/-9v feature, you can leave off D1, D2, C1, C2 and C6. These are needed only for 18v or regulated supply lines.

The only other thing is don't forget to wire ground out of you main board. If you only have one spot for ground, then you can wire the ground from the RR somewhere else, like a jack. The battery can be hooked up as you would any other +9v config---pos side to the DC jack and neg side to the ring of the input jack, for example.

[lincolnic]

That's exactly the info I needed - thanks, Brian! Looking forward to the builds. (I just got my other order in the mail today - boards look great!)

[lincolnic]

Actually, one more question: Small Bear has the MAX1044A, but not the plain old MAX1044. Is this still an acceptable substitute for the TC1044? I can only find a datasheet for the MAX1044, so I'm guessing it's the same.

[madbean]

Yep, that's fine.

[lincolnic]

So I'm looking at these PCBs, and I want to make sure I have the grounding straight before I actually do any building. If I wire from the sleeve of a jack to G1 on the board, and then from G2 of the board to the ground on my ring mod board, is that right?

By the way, I can't believe how tiny these boards are. You could almost call them cute.

[lincolnic]

Just a little bump. Is my ground wiring scheme okay, or am I missing something?

[madbean]

Yep, should work fine.

[lincolnic]

Awesome. I'll let you know how it turns out!

[benevan]

I have a EPFM Fuzz that I have run on battery for years and never bothered to figure out how to operate on an adapter.

I am interested in doing this, but want to be sure about your wiring suggestion.

So, bring your DC jack 9v wire into the 9v input of the Road Rage. There, it will be filtered and reverse-polarity protected. You can simply take another wire out from the adjacent +9v pad to your board. Then, wire both the -9v and ground from the RR to the appropriate pads on your main board. Since you are only using the +/-9v feature, you can leave off D1, D2, C1, C2 and C6. These are needed only for 18v or regulated supply lines.

You mention 9V input and +9V and -9V output, however, on the schematic, it is ~18V and +9V and -9V.  I assume the 9V input is the ~18V on the schematic, correct?

[lincolnic]

No, the 18v pad is an output - it gives you ~18v (thus the label) for running effects at that voltage. The first +9v pad is your input.

[madbean]

You won't get exactly 18v out of the Road Rage, but you can get close. I found with a steady supply (9.3v from my Pedal Power) and using 1n5817 in place of 1n4001 I can get 17.8v out. The 5817 have a lower voltage drop which means just a tiny bit more voltage out.