Give me your opinion, Fuzz Face DC jack or not?

[soggybag]

I just drilled up some boxes for a couple Fuzz Faces. I'm at the stage where I can drill a hole for the DC jack or not. I could also build them using a negative ground, or a positive ground. If I go negative ground I can add a DC jack. From what I understand the DC jack is not a good idea with a positive ground Fuzz Face.

So the debate is, go positive ground without a DC jack, battery only. Which means I have to have a battery. Or go negative ground and risk the potential problems of negative ground Fuzz Face. But, I get the DC jack.

[Jhouse]

I'm a big wall wart buff, but I usually don't chance it when it comes to positive ground (I've had a lot of pedals break from reverse polarity). If you're using pnp transistors I think that you should definitely go with positive ground and no DC jack. It prevents so many problems.

[John Lyons]

DC jack and a 1044 charge pump set to supply positive ground!

[azrael]

I use a DC jack for my PNP builds! It's not a problem is you have a power supply with isolated outputs.

[stezza]

I've just been through the same thought process with my tonebender.

I have a negative ground fuzz face clone and the tonebender is positive ground.

I really can't be bothered with batteries, I don't even include the snaps in my builds anymore. All you really need is 2 decent wall warts which put out >500mA and label one 'Positive gound' and the other 'Negative ground' or 'Normal'. If your likely to forget that its positive ground, you can always put a label next to the jack.

[Milotic]

couldn't you use a 1spot battery clip converter and connect it to the internal battery clip, then put the 2.1mm jack on the outside of the pedal, so it can be connected to a power supply?

[soggybag]

The question is whether I want to add the DC jack or not. I'm building the thing right now, I've got everything drilled and I tested all of my parts on the breadboard, so I'm just about ready to stuff it all in an enclosure. I can add a DC jack now or not.

[John Lyons]

Go for it. Add two while your at it. 

[snakey]

As a battery dies don't you get some desirable tones on fuzz faces? maybe dc with a dead battery simulator

[petemoore]

  test for shorts before connecting PS to 'it'.
  for Neg and Pos Gnd. circuits to work on a common supply, use charge pump to invert and supply the Pos Gnd one.
  Anything polarized of course can be reversed, but most users start with mostly NPN Neg Gnd stuff, 1 or 2 'odd' Pos Gnd. PS 'doorways'.
  Common thought is to connect both neg/pos to a common power supply but this is neg/pos connected=short.
  Dying and resistive battery mojo aside or on front burner, plenty of informations on this too, two 'sets' at least.
  Increasing resistance as some cell chemistry changes during battery discharge cycle, is part of the FF circuit possibility.
  As voltage drops then of course the bias is altered, there's less output and the tone/output level of course follows suit [regardless of the bias 'suit' it was holding, ie count yer winnin's or lossin's]...this can all be done with a 317 regulator.

[CynicalMan]

Another thing to consider is whether the power supply you'll be using has short protection. If it does, then I'd put in a DC jack. If it doesn't, then I wouldn't put one in without a charge pump or some form of protection. What EHX does on their positive ground pedals is to connect a 10 ohm resistor from the DC jack ground to the circuit/chassis ground. This means that the resistor will blow instead of the power supply, but it also means that EHX has to replace a 10 ohm resistor whenever a customer doesn't read the manual.

[Philippe]

I've got a DC jack on mine but never use it...prefer powering from one of those 9V Panasonic zinc-carbon batteries.

[Frances Rhodes]

DC jack and a 1044 charge pump set to supply positive ground!

hi everyone.
i'm new in electronics, so i tried to make a first easy circuit, and 2 weeks ago i made an AC128 Ge PNP fuzz face on a stripe-board.
and i'm experiencing problems with it.
i didn't use a battery, and replaced it with a DC plug and i can only get a faint dirty sound with the volume pot maxed out.
i read all the threads i could find about debugging but i can't figure out what went wrong.
i tested it with a BOSS +9Vdc 200mA power supply and no other effect between the guitar and the amplifier.
the LED lights up (well, used to... now it stays off, i don't know why) but i can't get a normally loud sound out of the pedal.
i didn't try it with a battery because i didn't think it could come from the supply, but apparently this could be where my problem comes from...
in case it works fine with battery, i'd be interested in the addition of a MAX1044 to power it up with external regular 9Vdc power supply.
i looked over google for information about it, but all i could find was the +18, +25, +33V from a 9V battery. where could i find information about the positive grounding issue, or schematics maybe?
thanks

f-

[petemoore]

  How would you like to power it/can it be powered that way is what it'll boil down to in the long run.
  Some have both batt and DC jack/input power-off jack-plug trick.
  What tends to dictate is what is the power supply ?
  If you have floating regulated filtered outputs for DC supplies then anything you want will work, including:
  DC jack
  DC Jack w/battery clip defeat
  Battery clip only.
  If you use reverse protection diode...[good idea for FF I think].
  If only the signal/sleeve ground is ground, then the other side of all supplies can be referenced to...gnd.
  It's when you connect a + to ground, then connect a - to ground when + and - don't mix = short.
  But there's a buncha other ways to mix up the power supplies...best is the floating output since it's never connected to anything until referenced to the signal ground when the sleeve connects to the DC jack - [in NPN Neg gnd. circuit.
  Before power is applied, test that all + and - conditions are not shorted.

[LucifersTrip]

I'd use a DC jack only if the original had one......haha

[Frances Rhodes]

actually i have the exact same problem whether i use a battery or a PSU...
i think i need a MM and post a debug thread somewhere

[mac]

To avoid this problem, and to avoid taking a PS with me when I play, I use bigger enclosures to hold 6 x AAA or 3 x 3.6v PC rechargeable batteries.

mac

[Paul Marossy]

Another thing to consider is whether the power supply you'll be using has short protection. If it does, then I'd put in a DC jack. If it doesn't, then I wouldn't put one in without a charge pump or some form of protection. What EHX does on their positive ground pedals is to connect a 10 ohm resistor from the DC jack ground to the circuit/chassis ground. This means that the resistor will blow instead of the power supply, but it also means that EHX has to replace a 10 ohm resistor whenever a customer doesn't read the manual.

And the customer gets to pay for getting it fixed, too. Win-win situation for EHX. 

[Hides-His-Eyes]

Single use batteries are horrible things, and generations from now people will be cursing us for ever using them.

a MAX1044 costs the same as three batteries, and you can easily fit one on a daughterboard that will slot in next to the DC jack.

[Joe Hart]

Put one in. Just because it's there doesn't mean you have to use it.
-Joe Hart