Failed EQD Tentacle

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Failed EQD Tentacle

innyve894
For my first pedal build I decided to do the EQD Tentacle. Here is the layout I used:

http://tagboardeffects.blogspot.com/2016/11/earthquaker-devices-tentacle.html

https://imgur.com/a/g98DP

The main problem is the low volume output. I measured the voltages going into the board as well and it's only at .8 volts with a fresh battery or adapter. When the battery is unplugged signal still goes through but at a low volume, and when the battery is connected the effect is barely hearable.

The bottom white wire is the input from guitar, other white wire is the output to amp. The green is input to the board blue is the output from the board. Below are the transistor voltages

Q3
C-B .74
C-E.78
B-E .37

Q2
E-B .02
E-C .75
B-c .71

Q1
C-B .69
C-E .75
B-E .25

Thanks in advance!
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Re: Failed EQD Tentacle

Travis
Administrator
Not sure if it's just because I'm on my iPhone but the link to imgur isn't working for me

Sounds like you definitely have a bad solder joint, misplaced wire, link, cut, or somethin
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Re: Failed EQD Tentacle

ξεναγος νεκροπολης
hi there my friend! your board looks a bit messy..lots of possible unwanted bridges. take a razor or a knife and clear the lines and the cuts. there is a diode in the wrong way(D3) too. and all of your soldering (including the 3pdt switch), is somehow dangerous!!!...are you runing your iron to hot? everything looks a bit burned. what iron do you have?
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Re: Failed EQD Tentacle

innyve894
Thanks for catching that diode, I've looked it like a thousand times and couldn't see something wrong. I have a weller wps18mp but I'm using a good bit of flux too, and by the time I got to the switch the iron was crapping out on me. Now the tip won't hold the solder it just beads off. The replacement tips are almost as expensive as the iron itself so I might just upgrade but I don't really have the money. Also the only solder I have is lead free so that is maybe why it looks that way. I did clean it up a bit more that what's shown in the pictures. I'll change the diode and see what happens.
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Re: Failed EQD Tentacle

ξεναγος νεκροπολης
i have a cheap one exactly like this
https://www.amazon.com/Stahl-Tools-SSVT-Temperature-Soldering/dp/B0029N70WM

i have it for like 4-5 years and i didn't even had to change the tip!!!18W are too low...that's why your switch and board look like that. you need more time for the solder to melt, but this destroys the board and plastics on the switch. we have a 18watt weller in our lab too, and i can't properly solder anything...it's for other jobs i believe.or smd maybe? i don't know...anyway...you should get an other iron i guess
cheers
Savvas
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Re: Failed EQD Tentacle

Silver Blues
Oh gosh yeah dude there is a lot of burning going on on both your board and your switch; I agree with Savvas 18W is far from enough power for anything in these applications and even worse for lead-free (the lead-free solders melt at higher temperatures so you're doubling down on the destructive lag time from the low-power iron). I would recommend investing in a good quality iron and good quality solder as soon as possible; no matter what you do your pedal won't work unless everything is put together properly! Everyone on here will give you different but equally good suggestions on what to buy, I'll just give you my own and say that I am using a Weller WP35 and either 63/37 no-clean flux core or 2% silver-bearing rosin core solders (with the silver-bearing stuff being superior).
I stand watching the steam-liners roll by...
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Re: Failed EQD Tentacle

innyve894
Is it still salvageable? I'd rather not waste a lot of time if I should really just start over. I switched the diode, still no luck but I am getting 9 volts across
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Re: Failed EQD Tentacle

rocket88
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it may be, but i have to agree with what's been stated above about the soldering and there's a lot of burn through, especially on the switch and wires. i've found that very rarely is a build completely gone. you may be able to save it by desoldering and resoldering with a more appropriate iron, and reduing the wiring. it's all about do you want to spend the time to do it all.

the two soldering stations suggested at good units, and relatively inexpensive. personally though, if you're just starting out i wouldn't get one because setting the temp is an obstacle when you're just starting out, since you need to make sure it's set at the right temp to get good results. personally i would suggest getting something like this, you could even go up to the higher wattage one if you need to, here. it's the newer version similar to what i learned on, which was my dads old weller pencil from the 60's. after awhile i decided to up my game so to speak to a soldering station mostly because i started selling pedals due to a lot of requests from people, and went a little over the top and grabbed and edsyn 951sx, which is commonly used in electronics manufacturing and fairly inexpensive comparable to many other industrial soldering stations.
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Re: Failed EQD Tentacle

Silver Blues
Rocket is right in that it may be salvageable, but I personally would just start over at that point. Grab some good tools and a fresh piece of board and you'll find it will go super smoothly.
I stand watching the steam-liners roll by...
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Re: Failed EQD Tentacle

innyve894
I just realized I made a stupid mistake, for some of the project I used plumbing solder (it didn't say plumbing on it so I assumed it was okay http://www.oatey.com/products/copper-installation/lead-free-wire-solder). Would it make a huge difference in the electric viability of the circuit? Can I just go over it with electrical solder or should I really just scrap this project now?
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Re: Failed EQD Tentacle

rocket88
Administrator
Haven't done that so I can't say for sure, but that I will say is that plumbing solder and electronics solder are for completely different purposes. Right now I would make the following suggestions:

1. Get a soldering iron that's for electronics work, like the ones suggested above.
2. Practice soldering on a blank board without using components to get a feel for the timing and getting nice solder joints.
3. Start from scratch and rebuild the board with new components to prevent contamination from the plumbing solder.