fuzzface doesn't know the tune (hum problem)

[pinkjimiphoton]

ok, so i bought a new pedalboard, and have it all wired up etc..



works great. so i figured i'd take the plunge, and add a max1044 charge pump to my venerable fuzzface,  i connected the  ground from the daughterboard to the ring of the input jack, -9v to what used to be the ground, and +9v to what used to be the b+(actually ground, being a pnp).

works great. totally awesome.

until i turn my guitar down. then it hums like a freakin' diesel. it's horrible. if the guitar is off, it's unuseable. with the guitar up just the slightest bit, it's dead silent.

wtf? any ideas? i know this has been brought up before, tried using the search but no luck, must not have the proper keywords.

wondering if it's a shorted cap across the PS input jack? this has me on the verge of tearing everything apart, but it works perfect until the guitar is all the way down...

so i'm asking for help and advice, which will be gratefully accepted and appreciated!!

coffee break's over, back on my head...

thanks peeps..

[LucifersTrip]

I think the first thing to do is check if the same things happens with your other FF's...you have to have more than one !

[bluebunny]

coffee break's over, back on my head...

LOL!    Still laugh at this joke...

(BTW, no idea about your hum problem.  Sorry.     But thanks for the chuckle!)

[induction]

The usual solution is a small resistor in series with the input. Test different values to see how small you can go to avoid changing the tone noticeably.

[pinkjimiphoton]

i hoped someone would get that joke!!!

dave, believe it or not, i only have this ONE fuzzface, it's the only one i use... all the others i've built have gone, either sold or gifted away!!

i will try the small resistance... (maybe a 1k pot as a variable resistor?) in series with the input, thanks... maybe it will help.

i got most of it gone.... by adding a huge power supply filter, with 220u, 220p and 1n4001 reverse biased to ground, a 220r resistor in series with the power supply before all this mess, and a 1n4001 in series to protect against voltage spikes.
now i can turn the guitar down and it's silent on the battery, but running on a wart still causes some noise.

i THImK what may have happened was i had a 100u cap across the supply... but it was only rated for 10v, wondering if maybe it was shorting internally?

i will try the small resistance, and see if it works... thanks for the tips bros!!

[rousejeremy]

I'm pretty sure that  every Fuzz Face I've made picks up radio or makes noise when engaged with the guitar volume off. I don't get it at all.

[pinkjimiphoton]

this is only with the power supply, and i tried several. with a one spot, it's not just motorboating it's hissing. with a boss, it seems to work ok now... with the gator one built into the board, no dice even with the charge pump.

and with a battery it's dead silent. oy. makes my bwain hurt!!!!

[induction]

All of my fuzz face hum and noise problems disappeared when I started using regulated adapters (or a battery), including the big jump at zero volume on the guitar, but I've only built an NPN silicon version. I don't know how feasible regulating is for you. It's easy enough to make a regulated adapter or put a regulator in the box, but you need to give it 12V or more. I've never explored the combination of regulation and charge pumps. You may need to do the regulation after the charge pump instead of before. I'm not sure.

[pinkjimiphoton]

hey induction, i'd think the reg would be after the charge pump, and is a great idea. i could step it up to 18v and then regulate it down i guess.
in the end, i tried the last trick, the resistor in series with the input. i found in my case a 220r resistor did the trick... but on a battery, the "blow" is ridiculous coming from it being a carbon comp i guess. whatever. i'm gonna run it on a power supply anyways, and with the power supply, problem seems to be solved. fuzz face still sounds the same (i set it up with an external pot to adjust for bias in these crazy new england wait 5 minutes and watch the weather change kind of way. ) and now it plays nice with the rest of the toys. and when i turn the guitar down, it's quiet... thankfully!! so thank you inductor, you cracked a nut i've been dealing with intermittently for like 2 years now. i love the tone of the box and have lived with it's quirks, and it's my main sonic ingredient ...may seem counterintuitive for a blues player to use a fuzzface to some peeps, but there's so many shades at your fingertips with just that one box, it's amazing.
i tend to run the fuzz about 1/2 way up, volume the same, and bias by ear so it goes real smooth from off to on, then from cleaner than clean to hendrixian scream. i farking love this pedal. and now my old-guy back will be happier, cuz a whole lot less bending is gonna be involved. win-win!!

thanks dave, rousejeremy, induction and bluesbunny.... wanna cup of coffee?

[induction]

Glad it worked out for you, Jimi.

Random fact: I went to high school in Storrs, lo these many years ago. Small world.

[bluebunny]

bluesbunny

Brilliant typo!      Now why didn't I think of that??

Glad you got it sorted, Jimi.  And yes, I'd lurve a coffee.   

[pinkjimiphoton]

@ induction, no way.... i lived there from 62-64, when we moved to willimantic. it IS  a small world!!

at bluebunny.... coffee break's over... soon... wanna nother cuppa?




people... before ya freak... google : http://www.sjacob.org/home/humour/BackOnYourHeads.html