Turning a Onespot into an isolated power supply

[GrooveChampion]

So i have this Onespot i dont use. I thought about taking out the supply itself and putting it in some sort of enclusure with multiple outlets, each being isolated. I remember seeing someone veroed something like that.

Also, how can I add a ground to the onespot?

[Travis]

Contributions > utility power etc > rockets voodoo labs supply thread

[Chris S]

You can put the the one spot into an enclosure with multiple outlets but they won't be isolated. Each isolated output will be from a different transformer. You could add a ground to the one spot but this well be unnecessary if your amp has an earth pin which will be connected to ground on the guitar came and in turn connected to the ground on the one spot. Hole that helps.

[GrooveChampion]

Wait so isolated output are transformer dependent? You mean like the standard 1:1 audio one?

[rocket88]

You might want to give this a read. In all honesty I don't think you really need an isolated power supply, unless you've got ground looping issues. It's more important to have clean power, i.e. Filtered and regulated, coming into your pedal.I've built a few power supplies based on the layout I posted in the contributions section that induction and I did, Travis mentioned it, and it works perfectly. I've actually got to finish up one that's got 2 of them in 1 enclosure.

[GrooveChampion]

Here's the deal, I thought so too. I guess that isolated power outlets are to power supplies what true bypass is to tone freaks. So I'd prefer regulated to isolated....though I dont think you can go too far with this....so if possible I'd prefer to have both just in case.

The thing I dont like throwing things away and I like how the Onespot has a lot of juice in it, is it possible to make that layout of yours work with 9V? Or do I need to build a charge pump if I want to use the Onespot? Cos it DOES give 2000mHa and I AM a cheapskate when it comes to buying things that I already have or can build.

[Neil mcNasty]

I think you guys might be overthinking this a bit too much...
Some of the stuff you are talking about here, is way beyond what the most expensive pedal power brands have to offer.
Most of those only have a few regulators and are often daisy-chained on the inside.
The Spyder that Rocket links to, is far and way beyond the quality that you'll ever find from the (so called) pro's, and it is a heavy duty build from scratch power supply design. Not something that makes use of an already existing one-spot... Way overkill for what's being asked for.

As far as I can tell, you need something that is a notch better than just a regular daisy-chain at the end of your one-spot...
In other words: you just want a bit more separation than a regular daisy chain, so that it becomes noise free.
So you can either go for the suggested Voodoo Labs Power Supply thread and build that kind of supply.
But remember that your one-spot needs to be putting out 12v or more, if you use that design.
(regulators always need at least 3v more coming in, than it is putting out)

Or... If you have a one-spot that already puts out 9v... I would suggest the Huminator II
It is what I use for my leftover one-spots and it does the job perfectly without any issues.
Look here: http://guitar-fx-layouts.42897.x6.nabble.com/Huminator-II-Power-Filtering-tp36872.html;cid=1495823290306-962

If you look at the schematic in my first post:
What you got is a half wave rectifier (the two diodes) that remove any leftover ripple-current followed by a large cap, then followed by a "de-coupler" (a small resistor followed by another cap).
The decoupler makes sure that there is no direct contact between the different pedals. It creates a boundary so that they do not "see" each other, and therefore do not interfere with each other.

What I do is that I add as many decoupling sections as I want outputs, and mount it in an enclosure.
I always leave the one-spot out of the box to save space under my pedal board, and so that I can easily replace them if they break, or experiment with different ones to see which one give the best result.
If the one-spot is not 9v, but higher... I add a voltage regulator first, and then comes the Huminator circuit.
Works like a charm for me, and is often more than you get from most pro power supplies at the music store.

[GrooveChampion]

So like I was saying, isolation it to power supplies what true bypass is to delusional tone freaks.

[Addy Bart]

Hi Neil. I've got a question about the Huminator II... Should it drop the voltage by several volts? I've tried adding it twice now to a DBA reverberation machine clone that's noisy with a OneSpot, and both times it's not worked (I get a screeching noise when the pedal is on). I measured the voltage before and after the Huminator and its dropping the voltage to 5.8v. At first I thought it could be bad caps but I got the same reading on the second one I built. Does 5.8v seem normal?

The current draw for the DBA RM is 54mA... Could that have anything to do with it?

I've added the Huminator to several noisy fuzzes before, and it's worked fine, but I don't have any of those to hand to test the voltage drop, and I guess the current draw on those is smaller.

[Neil mcNasty]

The higher the mA draw, the higher the voltage drop is a drawback with the huminator circuit.
I have never experienced any drop greater than half a volt in the most extreme cases, by measuring the voltage on the board in the pedal when it's connected (but I have only measured a few of them in cases where I can notice that there is a drop)
It might be a good idea to lower the resistor and see if that helps.
I often use 33 or 47R Ohm resistors to reduce the voltage drop (something I should probably have mentioned), but I guess you can go lower as well...

[Addy Bart]

Cheers Neil. I used a 22 ohm resistor and that dropped the voltage to 7.8v. Thankfully that awful screeching is gone now.