why is my fuzz face eating batteries super fast?

[bobster]

hi folks-
i built a fuzz face 3 years ago and it has always been light on battery use until recently.
i had bc109c's in but recently found two NKT 271 on e bay and installed them changed polarity and it now sounds great. trouble is the battery is goin flat in less than 2 weeks and i am not even using pedal often.
it almost seems like the pedal is always 'on' even when jack plug is out of input socket.
any idea what could cause this?
could it be the NKT271s ? are they known to be thirsty?
its a weird one
thanks - bob

[Mark Hammer]

Check the wiring of the jack.  Stereo jacks vary with respect to which lug connects to which contact.  You wouldn't be the first person in the world to think they've wired up the jack correctly to provide for switching the power on and off only to find that the power can't be turned off...ever.

[bobster]

thanks mark,
i have made a rangemaster and tonebender [ pos ground ] and the jacks are wired identically to this pedal too and my electro caps are oriented correct  also.
its a mindfook! i have not changed the jack wiring in any way from when the pedal was working fine before with the bc109s
maybe the batteries im buying [ chinesecheap carbon zincs ] are faulty or something but they are also in the t/b and r/m and they are lasiting well so im stumped good here!

b

[R O Tiree]

Put the battery snap onto only one terminal. Then use your DMM in mA range and place the probes on the un-connected battery terminal and the snap terminal it should have gone on. If you get a reading with the input socket empty, then Mark is right. If not, it may be either duff batteries (unlikely?) or some other problem. A FF shouldn't draw more than a couple of mA, IIRC, maybe 10 or so with the LED on (depending on the current limiting resistor you're using for it).

Maybe that's the problem? Have you changed to a different sort of LED that needs more current to shine brightly so you put a smaller resistor in there?

[Mark Hammer]

mike's right.  Some LEDs can eat up more current than the very circuit they are being used with.  I always recommend use of a superbight LED (3000mcd or greater) with a higher-value current-limiting resistor (10k or greater).  It is also worth considering use of a physical surround (e.g., black mounting bracket instead of chrom or merely mounting against a light-coloured surface) that is dark enough to produce the sort of visible contrast that lets you get away with using even dimmer settings of the LED (i.e., upping the current-limiting resistor even more).

That may not be your current ( ) problem, but it's good advice nonethless.