Pedalboard supply idea...

I've been wanting to build a pedalboard and supply for some time and have decided to get my finger out and do it...

I have a nice 50VA toroidal with two 0-15V/1.67A secondaries and am wondering if this scheme will work with regard to isolating the outputs and eliminationg ground loops...

http://images.lilypix.com/albums/use...AL_PSU_02b.jpg

I know the first part works and produces a healthy amp or so of current without breaking a sweat... I'm hoping that by isolating the DC outlets both physically (they are plastic bodied affairs) and with the diodes as illustrated I might also eliminate any grounding issues. I do not have or use any positive grounded pedals...

Many thanks for any thoughts you may have...

All the best,

YR :D :D

Apparently this is how it should be done... from my great friend and designer of 100KV+ PSUs Nick Cohen...

http://images.lilypix.com/albums/use...DAL_PSU_03.jpg

Never say I didn't share...

:D :D

IDK Rob, what have I told you about being nice? Stop it! LOL

Quote:

---

Originally Posted by chuckocaster

IDK Rob, what have I told you about being nice? Stop it! LOL

---

A few chaps in another forum have convinced me it's a pile o' poo idea... so I'm back to waiting until Nick (the 100KV guy) gets back on Friday to consult him on their comments... The 'few chaps' are right (about the diodes isolating the ground loop thought) so...

There you go... there's gotta be a way right?... there's always gotta be a way... :D

Thanks Chucko... hope yer well bub :D

I'll open up one of my Voodoo Labs PP2 and see how they do it.

And I'm hanging in there man, not great, but better than I was.

5500 mAh LiPo #3S system, will run you board for weeks and recharges in 20 minutes. Light weight and no noise. Try it, you'll like it.

Yo Rob, you want me to open up that power supply and see how they do it? I'm sure there's a schematic of it online now though.

And, I like the battery idea OA! Seems like a cool way to go.

Quote:

---

Originally Posted by chuckocaster

Yo Rob, you want me to open up that power supply and see how they do it? I'm sure there's a schematic of it online now though.

And, I like the battery idea OA! Seems like a cool way to go.

---

No worries Chucko - I am rather taken with the LiPo idea... It's essentially 'wireless' and if the re-charge time is 20mins then it's a no-brainer. Compact, light... genius. :D

Quote:

---

Originally Posted by Offshore Angler

5500 mAh LiPo #3S system, will run you board for weeks and recharges in 20 minutes. Light weight and no noise. Try it, you'll like it.

---

Yeah - nice shout OA... I like the idea... I'm thinking 14.8V through a regulator or 11.1V straight through??? How're 9V pedal going to react to 11.1V?? Really like the idea though!

:D :D :D

Quote:

---

Originally Posted by yankeerob

Yeah - nice shout OA... I like the idea... I'm thinking 14.8V through a regulator or 11.1V straight through??? How're 9V pedal going to react to 11.1V?? Really like the idea though!

:D :D :D

---

Most effects are happy up to 12 volts. They often have rudimentary regulating supplies because remember, the typical 9V is discharging from day one and will be down to about 5 before it gets replaced.

I put an LM335 with a I-can't-remember-how-many-Ohms trim pot on the bias leg. It was an old 10-turn I had laying around and I run about 9.5 volts. I'm going to switch to NiMh batteries since the LiPo's require a fair bit of maintenance and if you ever leave them on and forget about them you can run them down past 3V per cell you've destroyed them. Something like this:

http://www.batteryjunction.com/935hiponibaf.html

I think 3800mAh should be fine but I can put two in parallel for 7600mAh which should last about the same as 19 9v batteries, and then you recharge it! I figure 1000mAh per effect which is way overkill since you won't have all of them on at the same time.

Battery technology is so good today there's no reason to be mucking about with power cords.

Bring the AC supply in your gigbag as a backup.

BTW, there are commercially available LiPo effects power units on the market now, I'm just using the packs for my R/C airplanes which are no longer flight-worthy, and I'm an engineer. That's why I do the mad scientist thing with them.

Quote:

---

Originally Posted by Offshore Angler

BTW, there are commercially available LiPo effects power units on the market now, I'm just using the packs for my R/C airplanes which are no longer flight-worthy, and I'm an engineer. That's why I do the mad scientist thing with them.

---

I was thinking of using a couple of 1N5401s - one on each side of the load - to lose a coupla volts or so... that'd work wouldn't it?...

Totally cool idea though and the batteries aren't that expensive - I've bought a couple 5.5Ah 11.1Vs to mess around with and a balancing charger... :D

Quote:

---

Originally Posted by yankeerob

I was thinking of using a couple of 1N5401s - one on each side of the load - to lose a coupla volts or so... that'd work wouldn't it?...

Totally cool idea though and the batteries aren't that expensive - I've bought a couple 5.5Ah 11.1Vs to mess around with and a balancing charger... :D

---

I think of those as rectifier diodes, I guess - but for $1.50 US you can get a good regulator like this:

http://comingsoon.radioshack.com/rad...t/2761778.html

And keep the voltage constant as the battery voltage drops down to 9V or wherever you set it and you can get 1500mA out of it.

I'd considered the regulator - and even have a few L7809CVs kicking around somewhere - with a bit of luck they might even be L78S09CVs...

I wondered if electrolytics would be necessary but I'm guessing not as it's a battery...

Again - good shout bud! :D :D

Quote:

---

Originally Posted by yankeerob

I'd considered the regulator - and even have a few L7809CVs kicking around somewhere - with a bit of luck they might even be L78S09CVs...

I wondered if electrolytics would be necessary but I'm guessing not as it's a battery...

Again - good shout bud! :D :D

---

Rob, you could put a capacitor across the output to smooth any dips when switch gets pushed, but it's not required. We're not dealing with milliseconds here. And yes, you're getting perfectly smooth DC power from the batteries so hums and hisses are history. Just like changing the filament heaters in an amp to DC.

It's a no-brainer. The pedals were designed for battery power!

Have you seen Pedaltrain's Volto?

If you're just powering a few pedals it looks like an interesting alternative.

http://www.pedaltrain.com/volto/

TT