The Official Logan 5 Ring Mod build thread

[nbabmf]

I'm going to walk through each step of building this pedal here. Question, comment, flame away!

While my soldering iron heats up, I'm going to eat a donut. While I do that, feel free to peruse the PDF build guide:
http://www.forrestwhitesides.com/files/ ... _Guide.pdf

[nbabmf]

First, lay out your parts. There should be:

one 1N4001 diode
two resistors (10k and 100k)
one trimpot (100k)
one ceramic capacitor (.001uF)
three film capacitors (0.1uF)
one electrolytic capacitor (100uF)
one 8 pin socket
one LMC567 IC



The color codes for the resistors are:

10k - aw fuck, what is it
100k - goddamn, I can't see these things

If you're colorblind like me, just use your handy-dandy multimeter or ask your girlfriend. Otherwise, use this chart:
http://olcircuits.com/documents/resisto ... charts.pdf

[nbabmf]

The easiest way to populate a board, without parts falling out all the time, is to take the lowest profile components and put those in first. If you're not cool like the pros* and don't have one of those things that holds the board for you, this makes it easier to flip the board over and set it on your work surface without it wobbling all over. The lowest profile components are resistors and diodes, so let's put those in first.



Bend the leads inward a little so the parts don't fall out when you flip the board over.



Now solder them bitches. Remember to heat the component lead as well as the plated hole of the board, then apply solder to them... not the iron! It should only take a second to heat up, so don't go cooking your components.



*I'm not a pro. I couldn't master the board holder thingy, so I do it the flat surface way. I'm still cool, right?

[nbabmf]

Next up is the IC socket and the ceramic cap.

When putting in the socket, bend the corner legs in just a little bit to help it stay in place. DO NOT put the IC in yet.



Note the clean solder joints. They look like little metal Hershey kisses! Repeat this process for the film caps...



Trim pot...



And electrolytic capacitor, noting the polarity on the board (the little plus sign). The negative side is the one with the negative sign stripe down the body and the shorter lead, and the positive side has the longer lead.



And voila, a completed board. Also, DO NOT STICK THAT IC IN YET!

[nbabmf]

The hard part is done. Or is it the easy part?



Lay out your big parts now. There should be:

one drilled enclosure
one stereo jack
one mono jack
one DC jack
one cracker jack*
one monterey jack*
one 3PDT stomp switch
one LED bezel with LED
two pots (B10k and A100k)
two knobs (not pictured... yet)
two resistors (1k or 2k for LED, not pictured)
and
some wirez

Got 'em all? Now let's mount this stuff to the enclosure, which you may finish or leave raw as you please. It's aluminum so it won't rust. I polished mine with a little steel wool so it's harder to photograph without glare, and now I have the itchies.



Grab your trusty wire cutters and clip that little tab off the front of the pot so you can mount it flush. I prefer to hand-tighten things first. You never know when you'll want to remove something or change it's orientation. Definitely do not use Loctite or any other threadlocker haha. Notice that I mark the pots with a Sharpie, V for volume (A100k) and F for frequency (B10k) because they are only marked in one place, and that's smushed up against the enclosure now.

Note that the stereo jack, which is normally the input jack, is actually the output jack in this pedal. That's so the crazier people can plug it in (with the trimpot dimed) and actually use the oscillator bleed as a signal source.

*Oops, I ate these jacks. No can haz for u.

[nbabmf]

Now let's get back to the circuit board...

We need to attach our off board wiring. I always color code each section for the sake of simplicity and use a little more wire than I think is necessary in case I need to move things around or change something. You can always trim it down to size.



It's also good practice to tin your wire leads so they are stronger and take up soldering to the board, pots, etc. more nicely. Strip about 1/8th inch off the end, twist the wire with your fingers, and then apply a little solder to bind it together. Some of the board's holes are little tight (TWSS) for the 22 gauge wire, so don't glob the solder on. There were a few holes I had to stick bare twisted wire through. This is the sort of thing that occasionally happens when you are building a pedal, so being prepared is important.



BLAAHHH SPAGHETTI MONSTER

[nbabmf]

Looking at the back of the pots inside the enclosure, the lugs are 3 2 1 from left to right, just as they are numbered on the top of the board.



Next, solder up the 9V power supply wire to the DC jack. The ground (black) is the tab with the little negative sign on it and is the only folded one, and the 9V+ (red) goes to the outer tab next to it. DO NOT directly connect the board ground to the jack if you plan to use a battery. There is a way to hook this up so it doesn't kill the battery by switching the power on only when the pedal is connected. We'll use the input stereo jack for this.



Connect your board ground to the sleeve of the stereo jack. This is the center-most lug. The negative side of the DC jack goes to the ring, the middle contact which is connected to the shorter of the two prongs.



You may notice that the solder seems to have globbed onto the jacks. Sometimes contacts oxidize. The best way to prevent this is to scuff the area you will solder with sandpaper, steel wool, or a Scotchbrite pad.

[nbabmf]

Now, let's wire up the stomp switch for true bypass and the indicator LED.

When looking at the back of the switch, the lugs are like so:

1 2 3
4 5 6
7 8 9

A 3PDT switch is just three SPDT, or single pole double throw, switches. Lugs 1-4-7 are one switch, 2-5-8 are another, and 3-6-9 are the third.

For LED indicator wiring, connect the cathode (the short leg) to lug 2. This is done by looping and soldering a tinned wire around the lead and the other end to the switch. Connect the second board ground to lug 5. To complete the LED indicator circuit, connect a limiting resistor from the anode (longer leg) to the 9V+ terminal on the DC jack. I like my LEDs to double as the Bat signal so I used 1k for this LED. I'll include a 2k in the kits as well for a more subdued lighting. Go ahead and plug the DC jack in and a cable into the input jack. Click the stomp switch on and off to make sure the LED turns on and off.



For the circuit switching, solder the board in to lug 1 and board out to lug 3. (Yes, I know the picture is backwards... ignore that I fixed it.)Don't stick too much wire through so that the solder bridges between the lugs. After the solder hardens, I clip the excess to be sure it can't reach the lugs near it when I do the adjacent connections.



Then connect the input jack tip (outermost, unused lug) to lug 6 and the output jack tip (outermost lug) to lug 4. Bridge lugs 7 and 9 with a wire for the bypass. One of the resistor clippings works great for this.



OMFG we're almost there...

[nbabmf]

Okay, NOW you can put the chip in. Bend the legs inward a little bit so they are straight up and down, very carefully against the tabletop so it's even. Insert the chip into the socket, paying attention to the orientation. The little notch should line up with the socket, which lines up with the silkscreen on the board.

The trim pot inside adjusts the output and also has an effect on the oscillator noise level. I have it turned up all the way for the most output and the noise isn't really an issue. I have my little Ampeg GT-10 dimed right now and it's faint.

Screw on the bottom plate, stick the knobs on, and go rock!



And here's a clip:
http://www.box.net/shared/uvl42yamau\
... I kicked on a fuzzfaceless Mk1 fuzz about halfway through!

[culturejam]

Nice work, Nick!

[nbabmf]

You too, Forrest!

[nbabmf]

By request, here are a few mods:

Swap the frequency and volume pots. You'll get a wider carrier frequency range and the pedal will be loud enough to use as a boost. I don't know why I didn't do this to begin with.

If you're happy with the frequency range and want to maintain the fine control over it, but want more output, you can add a 100k resistor in parallel with R1, the 100k power supply resistor that's already there. You can do this after R1 has already been soldered in by making a little loop at each and and hooking it on the leads on the component side of the board. More output means more carrier noise, but I know not everyone will mind.

Drop the board inside a wah pedal and use your foot to control the carrier frequency. Most wah pots are 100k-200k, so the range will be pretty wide. Adjust the rack gear for the frequency band you prefer. If you don't want to drill the enclosure for an external volume control, you can use a trim pot for the volume control or connect volume lugs 2 and 3 with a jumper and lugs 1 and 2 with a resistor. 100k is stock volume output, but you can go as low as 10k. You can then use the trimpot to control overall output (and noise).

Use an LDR, a light dependent resistor or "photo eye", to control the carrier frequency. You can use a DPDT on-on toggle switch to make this switchable. Radio Shack has a pack of 5 for just a few bucks so you can experiment with light and dark resistances (the resistance when there is bright light and no light, respectively). I think one with a dark resistance under 500k and a light resistance as small as possible works best, but your mileage may vary. This is a fun mod because it makes the pedal act like a theremin.

Use a momentary footswitch (DPDT at least) to only turn on the ring mod while you hold the switch. A good example of this type of use would be ZZ Top's "Cheap Sunglasses" when you only hear the ring mod in the little licks after they stop singing (ie. 0:35, 1:04, etc)

Feel free to add your own as well!

[culturejam]

If you're happy with the frequency range and want to maintain the fine control over it, but want more output, you can add a 100k resistor in parallel with R1, the 100k power supply resistor that's already there.

Or you can use a lower value of the trimmer for Bias. Like 25K. You'll get a lot more output, but also possibly more "bad" noise. In most cases, the noise isn't a big issue, but I planned for the worst case scenario with the PCB.

[nbabmf]

Moar demo toanz:
http://www.youtube.com/watch?v=K36MN3cM6FQ
http://www.youtube.com/watch?v=U4WWgLX0DiE

The second clip has a Dwarfcraft The Great Destroyer clone for maximum robot sex noises.

[elbandito]

I got an extra resistor and no socket.