Joyo voodoo octave mod

Started by cheapgtrs, June 20, 2015, 07:28:57 AM

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cheapgtrs

So I'm trying to do the cap mod on my voodoo octave. I can't seem to get the caps out. This is my first attempt at modding a pedal and I'd like to not destroy the pedal. So I'm going very slow (maybe to slow) as to not damage the board. I can't seem to get the solder on the board fluid so I can ease the cap out. My question is would a heat gun be an easier way to do this? Any advice is greatly appreciated. Thanks in advance from a newb.

duck_arse

welcome to the forum, cheapgtrs. you might want to ask a moderator to move this thread to 'build your own stompbox' area, more people will look/see there.

do you have some photos of that which you are destroying working on that we can look at? and if you don't want to destroy the pedal, are you ok with destroying the coming-out caps? it is sometimes the easier way to wreck the caps, then clean up the board.
You hold the small basket while I strain the gnat.

bluebunny

Welcome along!  If the solder isn't flowing, then the iron isn't hot enough.  (Or the cap is attached to an enormous bit of copper on the PCB that's wicking away the heat faster than you can supply it.)
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cheapgtrs

My iron is 40 watt but it's a cheapo. Do you think it's not hot enough?  It will melt solder just not on the pcb. I'll put some pics up later. It's all disposable I suppose. I got 30 bucks in this thing so if I wreck it no biggie. Just trying to learn. I'm tired of paying for something I can do myself

cheapgtrs

Oh and please move to the correct forum.  My apologies

cheapgtrs


I lifted this pic from the net but the yellow arrows is what I'm working on

duck_arse

take note of the direction of the caps on your board before swapping them, or measure the voltages to see which is more positive. wreck the caps. you can use cutters on the top side, if you can get them under the body to cut the leads. otherwise, pry the body up carefully with a small screwdriver, until you're left with two stumps of leads sticking up outta the board.

then you can add some new solder to the pad, and reheat, either pull the pins out, or push them through with a needle or similar pointy. check for damage in the hole, check for continuity from top to bottom traces.

what is the values now fitted, and what are your intended replacements? 40W iron is enough to bring nearly any pcb to heal.
You hold the small basket while I strain the gnat.

cheapgtrs

I've read numerous threads stating that those 2 caps are in backwards. I'm not happy with the octave effect and have read this greatly improves that. So really I'm just looking to turn those 2 caps 180 degrees. I'm pretty new to this so I might be in over my head. I can wire up a guitar no problem but these components are so tiny.

duck_arse

welp, if you have a multimeter, you can find out for yourself. as noted, measure (black probe on 0V/ground/-/the black battery lead/jack sleeve/pick one) the voltage on each leg of the cap. which voltage is lower will want the white stripe, indicating the (-) side of the cap.

or, you can find some bi-polar caps of the same capacitance (the uF), and use those. they don't care about polarity, can go in either way happily. or, if the originals are 1uF or lower, you can replace with plastic film of the same capacitance, as they are not polarised, and won't dry/decay after 20 years. they are a larger size, mostly.

new electros will only cost you 10c each or so. it's not really worth trying to save those if they are problematic getting them out.
You hold the small basket while I strain the gnat.

cheapgtrs

Thanks for the advice. I'll measure when I get a moment. I'll let you all know how it turns out. It might be a week or so as this is the busy time of year for me. But.... fingers crossed. 

Blitz Krieg

When removing parts it is helpful to get the old solder flowing by applying a little more fresh solder.  The heat will be distributed quickly and evenly where the new solder goes.

idy

Newer pedals are often ROHS which means lead-free solder, which is higher melting temperature.