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This is The Evil Twin, or better Twins. They were built in a labour trade with dminner over a long, long period. I think we started planing sometime in February or March. Dan did the artwork, etching and painting, I did all the electronics. It's a dual reverb with a send-return loop in between the effects and an order switcher. This means that in/out 1 can go to either effect and in/out 2 will go to the other. If nothing is inserted into the loop, they are directly in series via the switched jacks.

The dark side is a DBA reverberation machine workalike with the addition of variable decay (btdr-3h brick) and some power filtering/polarity protection. Following my labelling scheme, I call it the "Rubidium Reverb." The light side is a spring reverb using the small blue 2 spring tank by accutronics. The design is based of the reverb section of a Fender Blues junior and I had to run through 5 designs. Mostly it was about the power section, as 9V didn't give enough clean headroom for the opamp. Had to go with a charge pump in the end. Also, because of the lowered input voltage compared to a tube amp, I had to modify the gain makeup stage and added a boost to the end to get it to unity and beyond. I achieved both with a LBP1 booster. This one's called "Ruthenium Reverb."

the dark side gets quite weird on some settings (just like the original), very spacy and ambienty but can also do clean, regular reverb. very versatile. The light side has very much treble, which I couldn't alter in the end. We think that might be coherent to the spring tank due to the small size. Nevertheless, it sounds quite nice up to half of the blend knob, then it gets a bit icy for my taste.

both projects are shared on OSHpark and the build docs are linked there. I hope some of you will build either one. I also shared the order switcher with the send/return option. No idea if that could have been done with a 3pdt too, but i couldn't figure it out.

Here's mine all finished up. I obviously got the Evil Twin with a worn in finish. Both projects are designed for all board mounted pots and switches, but I had to wire some of them in. Still pretty pleased with the wiring considering what's going on in there. The spring tank is mounted to the lid of the enclosure and sits right between/above the stomp switches. Yes, you can make it warble and make noise by hitting the enclosure. To be honest, even hitting the bypass switch will give some warble, which is hardly noticable if you engage while playing though.











Dan got the Good Twin with a nice, unbruised finish.




spring tank attaches comfortably to the pcb via these connectors.


Still missing some knobs...

Group shot:


Dan should receive his shortly. I hope he'll do a demo

Lastly, I've got one Ruthenium Reverb board (spring reverb) left, which is up for grabs. 10€ including shipping worldwide. First one to speak up in this thread gets it. paypal gifted please.

My latest creations, the Dubnium Drive (DBA Interstellar Overdriver) and Indium Indicator (VU meter designed around the LA2284 chip). Thanks to Cody for tech help with the transistor selection, which led to me discovering a layout mistake (flipped transistors). The indium indicator is using 0805 SMD components, except for the trimpot, IC and the SS12 diode which is a bit bigger than 0805.

The layouts are shared in my oshpark account (through hole and smd version for the Drive) and build docs are linked there.

The graphics are courtesy of Peter Repovski, who was nice enough to allow me to use the comic and sent me a high-res verision. Etched, painted, sanded and clear coated. Turned out perfect, but shows again I can't drill straight.









The video is just to show the VU meter. The sound recording is crap with my phone.

So, I finally finished this one. Had to redo the etching three times, because I wasn't content with the results. The third time the depth was very low, but I just couldn't be arsed doing it again. It was supposed to be a two-coloured design with the squares on the bottom part filled in with black, but I've lost most of it while sanding. Also, I've used primer for the first time, which seems to make the paint way more durable.
In the end, I went with a used look. because of the low depth I sanded into the lowered areas too, so I just went ahead and sanded the whole thing and worked the corners and such. I like how it turned out, even if it wasn't my initial intention.

I had to take the whole thing apart. I had the sequencer going, but the pattern indicator didn't light up and no effected signal was coming through. As suspected, the sequence was going to GND after the step LEDs. Turns out you can't even buy LEDs @ tayda anymore. ALL the leds had bare leads instead of being covered by the plastic lens/housing. A few layers of nail polish did the trick though.

Very fun circuit, I still have to play with the internal trimmers. Thanks Brian

     

     

does anyone have experience with simple scopes like this?

http://www.ebay.at/itm/DSO138-Digital-Oszilloskop-DIY-Kit-1Msps-200KHz-2-4-Bandwidth-Probe-Case-/262503127460?hash=item3d1e67d9a4:g:wgEAAOSwnNBXaemI

would be cheap and could just work well enough for setting up analogue delays and checkinhg easy things...

I'll just leave that hear. Reverse etched "Delayrian" (badumm tiss!), 4x MN3008 from Paul @ diyguitarpedals.au I've got quite some time ago. Still need to fine-tune the biasing, but it's pretty good as is.

         

A friend of mine wanted to do SMD, so I designed a TS808 pcb in SMD for 1590A. It turned out pretty good, the only thing I miscalculated was how little space there is in 1590A's. Now I remember why I've only built one so far . I designed the pcb for board mounted pots, but should have turned the top row around so they are under the pcb to gain some space. worked out in the end, but it was a very tight squeeze with the Lumen; a 3PDT would probably be easier to do (the last picture was taken during wiring to show how close it actually is).

Anyways, the design is a stock TS808 basically copied from Brian's 'Green Bean' project. I've added extra diode pads, so one could use symmetric, asymmetric Si or Ge diodes if preferred. I went with the stock 1n914 symmetrical option. The updated pcb is shared on oshpark with a linked build doc if anyone is interested; also I corrected a mistake of v1.0 which had a wrong transistor pinout, so I had to flip them for my build.

Reverse etch with metallic green. Lower part has a blue flip-flop on top with a gradient towards the lower end. It's hard to capture on photos, but it actually changes colours depending on the angle you look at it. The graphics are partially taken from the schematic. don't try to build it going from the exterior graphics though :p

             

Hi everyone,

I'm prototyping for a cooperation with Dminner atm, but I'm having problems with my charge pump setup. Ideally, I want to create +15V-15V from a 9V input. I wanted to do so using a LT1054 Charge pump and the circuit depicted on page 18 of the data sheet (http://pdf1.alldatasheet.com/datasheet-pdf/view/112438/TI/LT1054.html). I drew up a layout, etched it and totally screwed up getting only +6V and -0.3V...
So, I had another go at it today with a very layout that checks out as far as I can tell from the layout. the problem with the etched one was too little spacing and a very tight layout. Anyways, I managed to brake off a leg of my last LT1054 charge pump and wanted to know if its interchangeable with a 7660SCPA (http://pdf1.alldatasheet.com/datasheet-pdf/view/75092/MICROCHIP/TC7660SCPA.html) or 1044SCPA charge pump that I have on hand. The pinout is the same, yet neither of them has the schematic for the voltage doubler/inverter in the data sheet. It only has the one for voltage inversion and positive doubling, so getting +18/-9V.

thanks for looking

Went out of work today to find this in our University's yard: a freakin' robot band! How awesome is that?!? there's gonna be a "maker's fare" of some sort.





Also, I just handed in my PhD thesis. After 2.5 month of constant work, 6 days/week, 60-70 hours/week including stress-induced Tinnitus (hooray!), I'm finally done! you can't imagine the feeling when you slowly rename a pdf "Dissertation-Felix...pdf" Glorious! Enjoy your weekend!

I finally finished Jon's Tap Tempo Cardinal Tremolo yesterday. I really like the sound!
I had a broken electric cap killing the supply voltage. Of course, I had already boxed it, because it had quite a bit of offboard wiring involved. Taking it out wasn't as bad as I anticipated, but at least I figured out the problem fast enough.

Enclosure is etched with NaOH. Because of the fine lines, I didn't sand the surface, but rather scratched the paint off the raised parts with a syringe needle and a spatula under a magnifying lamp, which took me about 1 hour and explaining what I'm doing late night in the x-ray lab to a professor

     

     

[7.5]

hey guys,
Finished my total recall today but I'm not getting any love from it. started the biasing procedure but not a sound from the first MN3008 (got them from Paul @diygp). Started taking voltages and I traced the problem to the NE570 compander (got that one from banzai). all voltages check out except for pin 5, 6 and 7. Here are the values, wrong values bold, should-be values in brackets.

NE 570 (all values negative)
13.8   13.8
13.0   13.0
13.0   13.0
14.8   0
7.5 (13.0)    13.0
7.5 (13.0)    8.6
13.5 (4.7)    6.7
13.0   13.0

Supply is the recommended EHX PSU, I'm getting -15.07 V from the 7905 regulator, so that checks out. As a consequence of the increased output voltages from the ne570 (pin 7), also IC3 A pins 2 and 3 are increased. Readings for CD4047BE are also a bit off, but not near as drastic as the NE570.

CD4047BE (all values negative)
7.46 (7.94)    0
7.63 (7.09)    7.4 (7.0)
7.57 (6.91)    15.0
0          7.5
0          7.5
0          15
15.07   15

I've checked the components around the NE570 (R9-R12 & C6-C10), all have the correct value, I also reflowed the area. I measured the components too, everything checks out, but I cant get a reading from C7. Could that mean, it's a bad cap and could that cause the issue? I didn't want to desolder right away as I hate doing that...

I also traced the signal, it reaches Pin 6 of the NE530. Nothing after it.

Here are some pics:

I don't know what this guy is doing for living, but I better hope he's a carpenter or something. Damn, this is impressive. Creative, innovative and really classy. Just amazing. Make sure to watch some of the prologue-making-of videos.

Hey all,

I'm just gonna leave this here. I had some hickups with my board design as I didn't correctly connect one trace, but figured it out eventually and could fix it. there are a few minor flaws in the etch where I've lost the toner, but nothing drastic. I have to order a clear knob without set screw though. Hope you like it.

     

Because we've unfortunately lost a lot in the server crashI thought that this was something you'd enjoy and I can show off my builds again!

Lectric FX Zirconia:



Grind Customs STM800:



Quantum Effects Osmium OD (Klon of my own design):

 

Another GrindCustoms STM800 build to JTM45 specs with a 12AU7 and 12AX7 for a student of mine using Jubal's Whiskey River graphics (thanks again Jason, he's loving it!):

     

Multi for my brother's 30th birthday (buffer, TH Dr. Phil, GC Fluff Girl, TH 5-band EQ):



Zero Point SDX 2:



Quantum Effects Plutonium PSU (9V, 2 rails, my own design):



Quantum Effects Erbium EQ (SJ Effects Tonmeister with sliders, my own creation):



Madbean Rustbucket:



I hope someone else will do a sum-up too. I really enjoyed all of your builds one after the other, would be awesome to see them all in one spot.

I'm wondering what the purpose of D3 (1N4742=12V Zener diode) in the sunking is. I've also seen it on another schematic of a Centaur. First I thought polarity protection but this is done by the FET in the sunking, isn't it?
A though just hit me: could it be for overvoltage protection in case someone feeds 18V into it? doubling the 18V to 36 with the charge pump would most likely fry the opamps... If so, wouldn't it be better to use a 9.1V Zener?
Enlightenment would be cool. Thanks!

EDIT: scratch that. Google was my friend redirecting me to an old thread: http://www.madbeanpedals.com/forum/index.php?topic=685.0

In short: polarity and overvoltage protection for the charge pump. 9.1V would work too

Sorry guys, this is going to be a rant story. But I feel that I should share my most recent experience around here to spare you the hussle in the future.

I placed an order with Futurlec in mid February consisting of 3 log slide pots, 9x 50kB slide pots and 4 slide pot knobs. All of them were listed as 'in stock' and were way cheaper than any other source I could find, so I though I'll give it a go. I had ordered with them before - LDRs for the doppelgänger - without any problems. So, time goes by and nothing happens. I contact them a month later to ask about my order and I got a quick repsonse that "only" 2 items (out of 3!!) were not in stock and they had problems to aquire them (50kB and knobs). They proposed I choose something else for the same $.
I responded rather harsh as the items were (and still are!) listed as in stock. I specifically designed a part in eagle to fit those sliders and designed a pcb around those, so going with a stereo slider would be a major hassle. I told them, I was happy to wait as long as I get my parts.
2 days later, I get another email saying my items have been shipped. I was surprised, but happy. I received the order today to find that they shipped stereo sliders instead of the mono 50kB and no knobs. On the invoice it said 'changed' and 'canceled' as remarks for sliders and knobs. They didn't ask me if I was ok with it. The stereo pots have a very different pinout, I will probably still manage to use them with some extra wiring. I'll probably have a look at the layout again to see if I have space to change to stereo sliders to avoid any open wiring on the pcb...
I guess they just assumed that stereo sliders will be fine and as they are more expensive as the mono version they cancelled my knobs as well...

Needless to say, I'll never order with them again. I wrote them another angry email just to let them know. I won't go through the trouble sending the wrong parts back and waiting for the correct ones. I would most likely never get refunded for the shipping and I don't wanna wait another 6 month...

/rant over

I showed my own layout of Fredrik's amazing Arcadiator a while back, so here's the finished pedal! So much cool sounds in just one box.

After I apparently hooked up 9V to my input on my first pcb, something smoldered; but as I couldn't find the part and everything worked perfectly when hooked up correctly, I was happy with it. However, during boxing I found that the IC socket for IC3 was too high to allow for top mounted jacks, so I had to desolder it. I screwed it up a little and was not sure if I fried the IC when soldering it in without the socket, as it sounded a little off. Long story short, I desoldered pots and switches and populated a second board. After fixing a solder joint on that one, it fired right up and the layout is officially verified, which is a big deal for me as it was my first ever layout I had fabbed.

As a side note: the third board is on it's way to Fredrik. I won't make it a shared project on OSH park as he is planing a webshop and there's already Ben's wonderful version at rullywow.com

     





One special thing about this pedal is that I made the knobs myself. A coworker had some leftover material for silicone molds which was just standing around going bad (theather stuff he used for making test specimen). So I made a mold of various knobs I had lying around, which worked amazingly well. The detail is astonishing to be honest. You can see the set screws and on one knob the silicone ran on top of the knob which resulted in the 'serial number' being on the final knob.
To make the knobs from the mold, I simply filled it up with Envirotex and let it harden. Due to the thickness you can't really get rid of all the bubbles, so I did another try with some green textile dye I had. Unfortunately the dye didn't quite desolve in the epoxy and turned out really dark - but you can't see the bubbles this way. After drying, its only drilling to 6.5 mm for the shaft and 2.5 mm for the 3.0 mm set screw.

I have to admit it was fun to try, but I probably won't persue it. The epoxy material can be brittle (see the top left knob missing part of the round bottom) and it's a pain to drill - makes a mess and you can't quite hold it just in your fingers (cut myself a couple of times). Using pliers will scratch the surface.
Anyways, here are some picks of the progress. The chickenheads came out best and were easiest to drill.

     

First off, big thanks to Paul (chromesphere) for the pcb via a christmas PIF. Sorry this took so long Paul.
Anyways, it's a modded Fuzz Factory workalike, if I'm not mistaken. Sounds awesome, VERY interactive controls and lots of fun to play. Have been playing Knights of Cydonia by Muse for some time now.

As I won this PIF by just blabbering after some other member that Paul is into Whiskey, someone (iirc it was John) suggested we should name the build Buzz Factory in regard to that. So I did. I was also looking for a way to incorporate chemical structures for a while now, so I went with an ethanol molecule for this one paired with a Breaking Bad font. Just fyi, ethanol is regular drinking alcohol. I got the structure from a database and adjusted it to my liking.

I had some hick-ups with the enclosure. First etching attempt was fine, but I realized after drilling that the left and right row of pot labels were switched, so I sanded it off and restarted. Second attempt I screwed up the paint (the one I got was not covering the aluminum too good and I couldn't sand it properly). Third attempt didn't look too good either. Next, I did like 6 toner transfers before etching the last time, which turned out rather good. Had some hydrogens disappearing, but they are covered mostly by the pots anyways. Also 'comp" is missing the P and 'drive' the E. I used 'Dupli Color' metallic paint, which looks fantastic and was easy to work with. I'll get a darker one for the next one as the blue is a little too light to get a good contrast.
I crammed it all in a 1590B, but didn't like the classic horizontal arrangement of the Fuzz Factory. It just barely fits, there's no vertical space left AT ALL. Top mounted jacks didn't make it better. Took quite some planing and wiggling around to make it work.
Sorry for the long report, here are some pics:

     

     

     

Ladies and gents,
I give you my try on a pcb layout on Fredrik Lyxzén's Arcadiator Blip-Blop Fuzz. I used Eagle for the design work and got it fabbed by OSH park, obviously. It's designed for all board mounted pots and switches for a 125B.

Populated it yesterday, hooked it up, something started smoldering (ICs not yet in - I think I managed to hook up 9V to the input), couldn't find which part as everything checks out and Voltages look good. Hooked it up again and it works like a charm without replacing anything!







I'll share the project shortly, if anyone is interested. There's also Rullywow's fabbed pcb version, which looks spectacular as well! Thanks to Fredrik for releasing this amazingly funny project!

The resolution is not great, but man this guy knows what he is doing! Chapeau, my good sir

I'm putting together my first mouser order as I can not find the slider pots with LEDs anywhere else. To make this worth my while and more importantly the shipping costs, I'll get a few other things I maybe don't need right now, but will in the future.
Is there something you'll always get from Mouser that I should add to my shopping cart?