All my builds eat up batteries when nothing is plugged in.

[soma89]

Hey there, I built a lpb1 and a rangemaster clone. They both have this issue where, when i go to plug em in after a while of not using them, the batteries are always dead. I've connected a multemeter in series and have discoverred they do both draw current.

This has been a problem woth my previous builds as well. Any idea how to stop this or correct this in any way? Thanks a lot

[Matthew Sanford]

Maybe a stereo out jack with the extra to battery ground, that way it connects to sleeve/ground when plugged in only.

[FSFX]

Hey there, I built a lpb1 and a rangemaster clone. They both have this issue where, when i go to plug em in after a while of not using them, the batteries are always dead. I've connected a multemeter in series and have discoverred they do both draw current.

This has been a problem woth my previous builds as well. Any idea how to stop this or correct this in any way? Thanks a lot

You should be using a stereo jack and wire the battery like shown in the drawing below for a Rangemaster.
Also make sure you do not leave the input jack plugged into the pedal when not in use as the jack completes the circuit for power to the pedal.


You can, of course, use a switch for bypass and to switch the power like the original Rangemaster did as shown in the following drawing.

[JustinFun]

You can, of course, use a switch for bypass and to switch the power like the original Rangemaster did as shown in the following drawing.

You can, but most effects don't like it and need a half second (or less but still audible) to power up.

Best solution of all - go battery free! No need for stereo jacks, more enclosure space to play with and better for the environment.

[GibsonGM]

If the input jack is wired properly, the pedal won't draw current when unplugged and the battery will have the same life expectancy as if it was sitting in its package. 

Since we're going "all electric vehicle" by mandate, one 9V battery will make exactly zero difference environmentally, given that there will be millions and millions of additional batteries being produced for all the cars and replacements too, using petrochemicals - that's a lot of mining, transport, industrial energy use etc, but that's off topic here.   (not that this will actually come to pass, but it's what 'they' have legislated).  If this is "official policy", we cannot view batteries as negative any longer.

[Clint Eastwood]

If the input jack is wired properly, the pedal won't draw current when unplugged and the battery will have the same life expectancy as if it was sitting in its package. 

Since we're going "all electric vehicle" by mandate, one 9V battery will make exactly zero difference environmentally, given that there will be millions and millions of additional batteries being produced for all the cars and replacements too, using petrochemicals - that's a lot of mining, transport, industrial energy use etc, but that's off topic here.   (not that this will actually come to pass, but it's what 'they' have legislated).

Off topic as it may be, of course it does not make exactly zero difference. If you add it up it becoms significant: worldwide some 15 billion batteries are being used and end up in landfills every year. So if everyone would do his tiny effort, recycle used batteries at least, it will make a difference.

[FSFX]

If the input jack is wired properly, the pedal won't draw current when unplugged and the battery will have the same life expectancy as if it was sitting in its package. 

Since we're going "all electric vehicle" by mandate, one 9V battery will make exactly zero difference environmentally, given that there will be millions and millions of additional batteries being produced for all the cars and replacements too, using petrochemicals - that's a lot of mining, transport, industrial energy use etc, but that's off topic here.   (not that this will actually come to pass, but it's what 'they' have legislated).

Off topic as it may be, of course it does not make exactly zero difference. If you add it up it becoms significant: worldwide some 15 billion batteries are being used and end up in landfills every year. So if everyone would do his tiny effort, recycle used batteries at least, it will make a difference.

The DRM takes less than 1mA so just make it solar powered.

[GibsonGM]

Cool project!   It'll be green once it recoups the energy that was used to create the cell from nothing, transport it, all that   Including the energy used to retool industry and all related costs - of which there would be many.  At present, I'm willing to wager the 9v battery may be the greener product.

Yep, 15 billion batteries/year sounds about right.  Now multiply that by about 3 billion, coming up.  Energy tech advancement is great (I don't think you'd find anyone in here against it!).   Just that to view it as a panacea is a bit...naive...maybe once we get fusion on-line, we'll be net zero *shrug*   
I'll do my little part once those in power do THEIRS      

(actually, I'm close to net zero...at least for heating. I use renewable firewood to heat, 100%.  Zero oil) 

[amptramp]

I always liked the idea of rechargeable batteries but the 9 volt battery format is usually only 7.2 volts in NiCd or NiMH batteries.

Laptops use 19 volt lithium batteries that would be ideal as a power source for an entire pedalboard.  You could use a switching regulator to bring the voltage down but you may not want to go down to 9 volts - adding a series silicon diode for polarity protection would be no problem if you ran off 12 volts.  If you had a rechargeable 3-cell lithium phosphate battery, you would get 10.8 volts (3.6 volts per cell) in a 9 volt battery format and it would be rechargeable.  I have seen lithium 9 volt batteries (3 volts per cell) and they are rechargeable.

But the suggestion to use a switching jack is a good one - as soon as you remove the cable, the unit is off.

[JustinFun]

I always liked the idea of rechargeable batteries but the 9 volt battery format is usually only 7.2 volts in NiCd or NiMH batteries.

Laptops use 19 volt lithium batteries that would be ideal as a power source for an entire pedalboard.  You could use a switching regulator to bring the voltage down but you may not want to go down to 9 volts - adding a series silicon diode for polarity protection would be no problem if you ran off 12 volts.  If you had a rechargeable 3-cell lithium phosphate battery, you would get 10.8 volts (3.6 volts per cell) in a 9 volt battery format and it would be rechargeable.  I have seen lithium 9 volt batteries (3 volts per cell) and they are rechargeable.

But the suggestion to use a switching jack is a good one - as soon as you remove the cable, the unit is off.

I'm idly starting to look into this with a usb-c power interface port controller. USB-c is so ubiquitous now that it's probably about time I learned how to get the juice out of it.

https://www.digikey.co.uk/en/articles/designing-in-usb-type-c-and-using-power-delivery-for-rapid-charging#:~:text=For%20example%2C%20USB%20Type%2DC,5%20amps%20(100%20W).

Leaving aside the environmental factors, 9v batteries run out, are expensive and verging on the obsolete. Couple that with the fact that it's cheaper quicker and easier to leave them out of a build completely, it makes sense to me to give them a miss. With the popularity of chinese-built nano-pedals people are used these days to pedals without a battery option.

[anotherjim]

On topic. Positive ground circuits are just better for beginners and occasional builders with a battery only. Get zinc-carbon if you must be green about it. We all need a little zinc and we are carbon.

[pacealot]

To continue on-topic, perhaps OP could post pics of their wiring, because it sure sounds like something a simple look-over would solve...

[pacealot]

And a mildly humourous semi-related anecdote: I had put a lot of work into fixing/modding an old Shin-Ei fuzz wah (the one with the Super-Fuzz circuit in it), and just couldn't understand why every time I used it and then put it away for a week or so (fully unplugged from anything), the battery would be dead the next time I pulled it out. It turned out that I was putting in the batteries such that, when I screwed the bottom hinged plate closed, the screw for one of the bottom rubber feet (which was, of course, continuous with the shielded box when everything was fully screwed together) was poking and making solid contact with the negative terminal of the battery snap! (I guess it was a good thing I didn't flip the battery the other way around with the positive terminal touching the screw, or it might have exploded inside there.) Sliding the battery about half an inch away from the screw (and shoving a little extra foam inside to keep it there) solved the problem...

[Clint Eastwood]

I always liked the idea of rechargeable batteries but the 9 volt battery format is usually only 7.2 volts in NiCd or NiMH batteries.

Laptops use 19 volt lithium batteries that would be ideal as a power source for an entire pedalboard.  You could use a switching regulator to bring the voltage down but you may not want to go down to 9 volts - adding a series silicon diode for polarity protection would be no problem if you ran off 12 volts.  If you had a rechargeable 3-cell lithium phosphate battery, you would get 10.8 volts (3.6 volts per cell) in a 9 volt battery format and it would be rechargeable.  I have seen lithium 9 volt batteries (3 volts per cell) and they are rechargeable.

But the suggestion to use a switching jack is a good one - as soon as you remove the cable, the unit is off.

All the NiMH 9v batteries I have used are around 9.5 volts when fully charged, and most of the time they will be between 8.5 and 9 volts.  7.2 volts I see only when they are really empty. But for things that use very little current, I think it is a bit of a 'waste' to use an expensive rechargeable battery...
An idea for a cheap power supply: old phone chargers are everywhere and can be of good use: since they are floating power supplies you can connect two of them in series, giving 10 volts. Then add one or two diodes, and voila.

[Mark Hammer]

Sadly, there is no universal standard for where tip, ring, ground and default (closed circuit) lugs are situated around the perimeter of a stereo or mono jack.  I've learned this lesson by falling prey to the problem soma89 describes, myself.  The only solution is to follow the path from jack contact to solder-lug visually, to verify what goes where on THIS particular jack.  I suppose it would help one used the same brand of jack all the time, but then so many of us only buy a jack here and there, and not in the thousands from the same supplier.  So we're always adapting to the "new" jacks.

Incidentally, I'll safely assume I am not the only well-seasoned builder who has foolishly and absent-mindedly soldered leads to the "other" set of lugs on one of this type of jack, and wondered why the circuit wasn't working in either effect or bypass mode!    Damned confusing symmetry!!! 

[antonis]

An idea for a cheap power supply: old phone chargers are everywhere and can be of good use: since they are floating power supplies you can connect two of them in series, giving 10 volts. Then add one or two diodes, and voila.

R.I.P. charging algorithm..

[Clint Eastwood]

I have tried it as an experiment, and it worked. As far as I can tell, phone chargers are just simple smps's, the charging circuitry and algorithms are in the phone. But maybe I was just lucky?

[antonis]

maybe I was just lucky?

Maybe your batteries were lucky..??

[Clint Eastwood]

To be clear, the phone chargers in series could power the pedal directly, I do not propose charging NiMH batteries with them. At least not without proper charging circuitry.
Actually, just putting a 22 ohm resistor in series with two phone chargers should be enough to make a simple 9volt NiMH charger. To be verified..

[GibsonGM]

I'm thinking a good amount of filtering would be required to use phone chargers for an audio application?