So I sold it thinking that I would have preferred one of the earlier versions that had a bit more girth. So if you too want one of the previous versions, I think this pretty much covers what the changes were. If you have any further info about differences I may have missed or other changes that may have happened, then please let me know and I'll add the different variations.
Revised layouts - March 2014
I have redone all the layouts because I could see they could be made slightly smaller, require only a single ground connection and make better use of the space.
has anyone built one yet?ReplyDelete
The spst toggle switch is on-on and the sw1c it is not used right?
If the switch has a third lug then it's probably SPDT rather than SPST which should just have 2 lugs, in which case use the middle lug and any of the other two lugs for the second connection. The final lug will be left unused.ReplyDelete
Which one is the right one? I am going to shy away from the V4 since it seems to have a short but effective editorial reviewReplyDelete
I don't know! :o)Delete
I've only used the V4 and personally I wouldn't bother with that. When I make one up I'll probably socket the Volume 3 cap and the 220p cap as well. A bit of trial and error with those two may get it sounding more to my liking.
Hi there, I'm a little late into this blog but I've built the OCD v3 and having problems at 18v. Is there a specific IC TL082 that should be being used? Any help here would be great.Delete
What do you mean having problems, it works at 9V but not at 18V?Delete
Every TL082 I've seen is rated at +/-18V and so is ok with a 36V swing, 0 to 18V should be no problem at all.
Thanks for the reply.When I use at 18v, it makes a whistling noise until you take it down to 9v. Particularly when turning Gain knob.Signal does pass through it, but too noisy to use?Delete
I've handed this over to a friend who is better than me. He managed to borrow a friends V3 and has found some interesting things about the way the original is made. Firstly the way the power track is run, is not entirely straight forward and at 18v may not be converting to vero board very easily. There may also be a possibility that on vero board the components are too close together to run at 18v. My friend is going to etch out a PCB and see what the outcome is.Delete
I've made much higher gain and tighter packed veros than the OCD which have worked no problem at 18V. There is no problem at all using even higher voltages than that with vero. Some people prefer PCBs and have negative ideas about noise and interference from vero builds, but having built lots of both I've never found noise to be any more of a problem than it can be in PCBs. One of the biggest culprits is interference because of the positioning of input and output wires and PCBs are just as susceptible as vero.Delete
Incidentally Lee, which charge pump IC did you use? Some of them do whistle if you don't have them configured in "Boost" mode because the oscillator runs in the audio frequency range. In boost mode they run somewhere between 30 and 40khz and so you don't get the whistling.Delete
I think you nailed that one (the whistling) (unless there's something wrong with my browser, there was no response?)Delete
From my perusing the datasheets, it seems pretty clear that the ICL7660 does NOT have the boost function. i.e., on the ICL7660 pin 1 is nil, no function... N/C (no connection), whereas on the MAX1044, pin 1 is designated BOOST, & when connected to V+ pushes the oscillator/switching freq. well out of audible range (6x boost):
From the Maxim Integrated datasheet:
(MAX1044) BOOST Function :
Frequency Boost. Connecting BOOST to V+ increases the oscillator frequency by a factor of six. When the oscillator is driven externally, BOOST has no effect and should be left open.
(ICL7660) NO Function (N.C.):
I have wondered about this as some PCB sellers throw in an ICL7660 with their charge-pump augmented pedals.. But they don't have a sw-freq boost... At least MXI's doesn't. This explains why the MAX1044 is consistently a buck or two more than the ICL7660.
btw: First post. I'll just say that IMFAO, tagboardeffects is consistently the absolute GO-TO DIY resource. You are awesome man.
i have built the V.3 it sounds greatReplyDelete
i have built the V.3 it sounds greatReplyDelete
Damn!! I'm getting nothing from V3?! just a loud pop when turning on and off... I'm not even getting a clean signal? even when touching the input jacks while plugged in, I'm getting nothing?ReplyDelete
Thanks for verifying Michael.ReplyDelete
If you're getting nothing in bypass Vince it sounds like a dodgy switch. Try desoldering it and connected everything up with terminal blocks so you've got a definite true connection and see what happens.
I'm an idiot. I wired the two lugs on the out put jack the wrong way round... All working perfectly now! surprisingly high gain! very nice.ReplyDelete
I did panic to as I'm getting far to cocky and just wiring the whole thing straight in the box...
Cheers Mark :0)
Is it just me that only finds 14 cuts instead of 15?ReplyDelete
I count 15 on all of themDelete
Hmm.. still count 14. Is there a cut underneath the 100ohm resistor? If so then it's barely noticeable =)ReplyDelete
Yes, otherwise the Tone 1 wire would connect to pin 6. You can see it on the bare board layoutDelete
I agree Mark, version 4 is cow pat!. What the hell were they thinking? I have verion 3 that I built from your layout and thats a really nice sounding drive/distorion but v4?! Thin/weak/harsh And that was tested through my spanking, shiny new SG and my Marshall DSL combo so basically if it that can't do it justice then nothing will :o)ReplyDelete
Aah you got it did you? :o) Excellent. Maybe it is something to do with the gear, SG into a DSL is a very similar setup to my Les Paul into a 6101 so maybe that just isn't a good combination for the pedal. I can't imagine it sounds that bad for everyone considering the amount of fans it has.Delete
Yes, the guy dropped it off... 2005 natural burst for £590!. I think you may be right, Gibson into a Marshall, putting a pedal in between that is like Ketchup on a steak!Delete
Version 3 sounds awesome. Careful with the layout, there's ground both on row 1 and the last row. I spent 2 hours debugging this only to find out I missed the last row connection to ground.ReplyDelete
Yes on a few of my layouts there are two rows that need a ground connection. If there's room I always include a link, and if there's isn't space for a link but the layout is small enough I will add another column to do it. But with this being 20 columns wide already I didn't want to do that, especially as it's easy enough to daisy chain the two connections.Delete
Any idea what i could have done wrong with my V3 build?ReplyDelete
I get sound through it, the tone and vol pots working as well as the switch for bright but the gain pot dosnt seem to react at all, i dont get any overdrive from it and i cannot understand whats wrong, been looking on shorts etc but cant find any.
tried switching the IC, changed pot for the gain but it still remains, the gain knob wont do anything at all while the tone, volume and bright switch works flawless. please help me on this one.ReplyDelete
We know the layout is verified so there must be something wrong with the build, or something wrong with at least one of the components. Take a high res front and back board pic and post the links to the pics here and I'll see if anything stands out.Delete
i've trying even more without progress.Delete
the sounds is really clear and the tone knob/switch react very well as well as the volume so i cannot for my life understand whats wrong with the gain since nothing happens when i turn it.
here are the pics:
thanks for any help!
I've just been over it and from the parts I can see there certainly doesn't seem to be any errors in value or positioning, and all your cuts are in the right place. With everything else seemingly working ok and the only problem being with the gain pot, the issue must be around pins 1 and 2 of the IC.Delete
Have you got a multimeter? If so put it in the audible diode continuity mode or resistance, and check for any unseen bridges over to the right hand side when looking at the track side. You shouldn't get continuity from any consecutive rows. Failing that you may have a problem with the 18K or 2K2 resistor, or the 220p or 68n cap. There's always the possibility that you have a poor solder joint somewhere so first try to reflow all the solder between rows 2 and 7 for everything to the right hand side of the IC track cuts, the top of the 68n looks a little dull to me but that may just be the light in the photo.
Failing all those things I'd suggest changing those 4 components one by one to try to find a faulty component.
Finally got around to test this out. Turns out that switching the 220pf tanatalum caps i used didnt work, which it should i suppose?ReplyDelete
Tried it with the regular flat brown ones and it works right away, could be that i have mixed the value of the tantalums when putting them in my assortment boxes, they say "BC 104", could that be 220pf value?
This comment has been removed by the author.ReplyDelete
hello, can i see the schematic?ReplyDelete
This will probably sound stupid, but are the red and white squares on the circuit the cuts? What are they, and what do I need to do to the circuit to put these "cuts" in? I'm a novice at electronics but I'm interested in building this circuit.ReplyDelete
Yes they're cuts and you can use a drill bit or have a look on eBay for a stripboard / vero cutting tool. The layouts show the top of the board so the cuts go on the reverse copper side so the bare layout you can see needs reversing right to left to mimic the track side and see where the cuts need to go.Delete
Okay, thanks for the info! Another thing whilst I'm here, on the diagram info where it says "tone 2 and 3 to ground" does this mean that the terminals 2 and 3 on the potentiometer go to the two ground wires? And so terminal 2 on the volume pot would be soldered to the output? Whereabouts is the output on the circuit? I notice that the input has been labelled on the diagram but I can't see where the output would go.Delete
Again, you can probably tell that I'm a complete novice at electronics. Thanks for the help.
All grounds are connected together, board, pots, input and output sockets, DC adapter and switch for LED. Most people use the input and output sleeves as central points for ground because the hole should be big enough to get a few wires in there, and by their nature they can take a bit of heat abuse for prolonged soldering. The output of the board is the Volume 3 wire, volume 2 is then the main output which goes to the switch.Delete
Having problems there.Delete
The Volume 2 lug goes to the output lug of the switch right ?
Then where does the Volume 3 from the board go ?
To lug 3 on the volume pot and to the toggle switch.Delete
The Volume 3 wire is the main output of the board, which is then attenuated by the volume pot and goes back to the stomp switch via lug 2.
Hmm that's what I did. Triple checked everything aaaargh!Delete
Does it matter where the ground wires go by the way ? I try to ground equally on both input sleeves, but is it a good idea ?
i built one of these (the V1) and every control works properly, but it's extremely bright, has very little low end (has lots of bass loss) with all of the controls at noon. there must be something awry somewhere but i've gone over it alot of times and checked everything. the clips that i've heard online sound pretty full and uncolored with the controls at noon and the drive at the minimum. any ideas of what i should look for?ReplyDelete
Hi Mark! After my third attempt at building the third version of this pedal, I'm getting somewhere now (I know, three times? What the hell?!) I'm getting distortion, but I'm also getting a lot weird feedback as well. The feedback is more prominent than the distorted tone and me playing.ReplyDelete
When I turn the gain pot, it seems to sweep through frequencies changing the note of the feedback. Only one of the toggle switch positions sounds the effect as well (I'm guessing because the switch I have is an "on-off" switch rather than an "on-off-on"?) Any idea what it could be that I've done wrong?
The switch should be just an on/off. It's simple make or break. The usual reasons for feedback is a poor ground connection or bad joint somewhere, so you're going to have to go over it all thoroughly and look for any problem areas. If you can post the IC pin voltages that may give some sort of clue, but it may not help too much if you are getting the distorted sound through it too, which suggests that things are mostly correct.Delete
Right okay. I've since re-soldered the wires to the gain pot as the connection looked like there was a cold joint, however it's still doing the same thing. I've also lightly scratched between the tracks with a stanley knife to prevent any bridges.Delete
Here's a couple of pictures of the circuit, the soldering I've done for the ground wires isn't ideal, I've got a massive mound of solder on the volume pot, so I'm guessing this is probably an issue, what do you think?
Circuit - http://i237.photobucket.com/albums/ff69/martinswain/IMAG0337.jpg?t=1351436588
Ground wires - http://i237.photobucket.com/albums/ff69/martinswain/IMAG0339.jpg?t=1351436589
Here's a recording of the feedback I was on about:
look your cap's..10uf,10uF,100uF..Delete
My build of ver3. It's quite gnarly.ReplyDelete
I'm not actually noticing any difference between "HP" and "LP" but it sounds so good I'm a little reticent about messing with it.. though I most assuredly will as soon as I come down from my pedal building high.
very very good sound!!! V3 i build, switch and pot's is work fine!!ReplyDelete
Anyone mind taking a look at this? I'v got two V2 pedals on my bench and can't get them to work. But it's weird cause i'v already got one that's working fantastic i did earlier last month...Anyway here's a few photos. Keep in mind, I'v reflowed solder, continuity checked everything..I just can't seem to find what i'v done wrong? Same issue, both projects. No nothing out of the thing.ReplyDelete
v3...i say for very god sound!i connect together the grounds normal, but...in "BYPASS" mode "switch-off ocd" i noticed that a i hear a litle feedback very low,and when i turn the "tone" pot changing the frequencie of the feedback.Very low but..??? why?? I guess with more powerful amp on stage going to bother me..ReplyDelete
How did you wire the stomp switch?Delete
Just like here..http://www.beavisaudio.com/techpages/StompboxWiring/Delete
battery + adapter. i take to my hands the stompbox and stop the noise ..or low more. is the groud's?
if i disconnect the battery stop the feedback.i thing the 2n7000 give me signal.Delete
vol-2 to down-right pin,
output jack to right-center pin
....i look all again.
The problem with that method of wiring the stomp switch is that the circuit is left powered and hanging when bypassed and it means noise can leak through the ground connections. To cure that you need to wire up the stomp switch as per my method here, which grounds the input to the circuit in bypass and so silences it.Delete
i try in morning! thanks!! if i put battery just i connect parallelsDelete
When you plug in a 9V adapter the battery is disconnected (as long as you've used a switched socket).Delete
The battery with this method maybe lose the power if i leave the pedal log time? The stereo jack is unuseless? Im confuse about this..Delete
I install mono jack input..and one extra switch for battery? Sorry for the many questions.Delete
please helpp! i have built and sold some pedals before, but this project gives me a high pitched squeal with gain over 3 o clock if everything is maxed!please helpReplyDelete
changing the 220pf cap at pins 1 and 2 completely removed it but...if i take out the cable from the input i get kind of the same thing...just a thought..anyone had problems? i read somewhere that others had issues with their builds too regarding high pitched squealDelete
changed to 680 pf was ideal for maximum settings...strangeDelete
the difference in tone is in the ballpark, i actually like it more this way haha
but nonetheless , could someone give me an explanation?
The cap acts as a filter which tames high frequencies. As you increase the cap value the bandwidth of the amplifier is reduced cutting high frequencies, so you've obviously increased it to the point where the problem frequencies causing the oscillation were removed, or at least reduced enough to stop it happening. If you want to read up on it do a search for the Miller Effect.Delete
Yes IvIark thanks. I am aware of this. I just thought maybe i did something wrong. Built it in a similar 1590B but smaller. Tried rerouting wires but to no avail. Only the cap change worked. Thanks very much for your layout! I love your blog \m/ already did 7 different things,and all are "gone" ($$) :DReplyDelete
The only thing I did is put a 4558 instead of the TL082,but this should not be a problem.Delete
Can someone put a wiring pictures of v3. I'm new to this and I don't know how to solder the pots and input and output for testing before attaching to the enclosure.
For the pot and stomp wiring you can see details here:Delete
For testing before soldering in the switch, just use a small terminal block to connect the inpput socket tip to the board input wire, and Volume 2 to the output socket tip. Then you can use the sockets you've mounted on the box to do the testing.
If you don't have a terminal block just twist the cores together.Delete
Thanks a lot for the info. To be more.specific I'm.doing v3 and it says for the gain terminal 2 and 3 goes to one place Should I solder terminal 2 of the pot with 3 and then trow a line out to board from terminal 3 or from terminal 2.For the tone I only se terminal 1 what shoul i do with the 2 and 3 solder to.ground?Delete
Yes it tells you the additional connections you need to make in the notesDelete
Loving this site! I built the OCD V3 and compared it with my Fulltone OCD V4 and V3 is way better. Don't bother with V4 like many here have stated. There is one strange thing though, fully counter clockwise on the volume knob there is no sound, then through the first quarter of the pot the volume is in a usable range. I was wondering what pot I could put in there to get a little better sweep.ReplyDelete
Yes a log pot would probably give a preferable sweep. In all honesty I don't know why linear pots are used for volume pots in most cases, but we keep the layouts true to the original.Delete
Awesome. I noticed V3 had a 500k lin and V4 had a 500k log, so that was going to be my next step. Thanks!ReplyDelete
i don't know if this helps but i have the OCD v4 and hated it when i got it (got it in a trade so i couldn't return it) but i took out the diode and now it sounds awesome, took out all of that nasty sounds. apparantly for the v4 they changed something with the tone control but i really like it. they call it the 3.5 mod cuz its not the same as v3 but more similar than v4 wasReplyDelete
Hi Guys, I finally finish the build but I'm not getting output. I follow the signal is getting into the op amp thru pin 3 then I'm not getting any out from the op amp. I tried checking it with the battery connected and also disconnected. Can some one help me? Sorry if I make dumb questions but I'm a newbie!!ReplyDelete
You should have the signal on the IC pin 1. Double check all the components and knife the strip gaps to eliminate possible shorts...Delete
How can I test the output signal because I used the signal tracer on the pin one and I'm not getting anything out from the ic. If I do the same on pin 3 i get the input but no out put. Also I checked the voltage and is getting voltage on pin 5.Delete
The layout is definitely verified, so if you're not getting anything on pin 1 - there must be something wrong with your build.Delete
What voltages you have on all the pins? Pin 8 should be 9V, Pin 4 should be 0V and rest should be close to vref, around 4,5V...
You I know is me not the board : ) I just need some help to see where I messed up! I will take the readings and let you know.Delete
You could post photos of the board too. But voltages should give us a clue...Delete
Pin 1 = 8.80ReplyDelete
Pin 2 = 8.81
Pin 3 = 8.82
Pin 4 = 9.29
Pin 5 = 9.47
Pin 6 = 8.48
Pin 7 = 8.82
Pin 8 = 8.87
I think the voltages are to high right?
Hmm.. You have all the pins getting supply voltage. Pin 4 should be ground, so it must be 0V - and only one where you should be getting ~9V is the pin 8. I'll check the pics...Delete
Ah. Found couple of things that might be the cause. The board needs to be ground at two points - one is the bottom strip and the second is the right side of the top strip.Delete
One other thing is that 10µ output cap at the bottom. It's upper lead goes to one row higher.
Not sure about the wiring though. Are the thin wires for battery? If they are, i don't thing you're getting the bottom row grounded. So you could try taking a wire from top row, right side to the bottom row. That would explain a lot.
Good catch on the cap placement. I'm fixing it now. Also on the bottom ground I'm putting the input ground wire and on the top right ground row I'm soldering the battery ground, the output jack ground wire, the tone 2 and 3. I think that should do it right?Delete
You would then need to have the input ground wire also connected to other grounds.. I would just take a wire from the top row (right side) to the bottom row using unused holes. That would eliminate the possibility of two ground loops. While the jack sleeves are grounded through the box, it would still be better to have just one ground connection coming to the board.Delete
Did anyone compared his build with the original pedal? I wonder if there are any sound differences?Please please let me know..ReplyDelete
I built V1, but I've got an issue. The gain and volume knobs seem to be fine, but the tone control and the switch seem to do little, if anything. Overall, the tone is what I would describe as "warm-to-a-bit-dark." There's no sizzle at all.ReplyDelete
Also, when the tone knob gets turned down, it kills signal when it reaches near the far low end of the taper.
Any thoughts on what may be going on?
An error on your build, bad joint, short or misplaced component. Been in similar situation myself a few times. Triple check everything. I would start from that tone pot connections.Delete
Got it! Not sure what it was, because everything looked golden, but I re-flowed again around the tone control components and then ran a blade between all strips, so it was either a flaky solder point or tiny bridge somewhere. Thanks for your work on the layouts, man. You're astonishingly prolific with these!ReplyDelete
I'm having trouble getting this to work. I'm trying V3. The schematics that I have found have pin 6 of the opamp going to 39k in series with 100n to gnu but the layout has pin 4 with 39k to gnd and pin 6 with 100n to gnu. I know others have got this to work so I am confused.ReplyDelete
No, the layout has a 100n from pin 6, and then a 39K to ground (pin 4 of the IC). There's a track cut separating the 100n/39K junction from ground on the top row.Delete
oops i see my mistake. I thought the whole top row was gnd but it is just the top corner.ReplyDelete
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Just finished version 3 build and I'm getting some output when the effect is engaged but I mostly get a hum and a hiss. Any ideas?ReplyDelete
So am I right in saying the only difference between V3 and V4 is the D1?ReplyDelete
Hi Everyone!! I have problem :( I made v3 and not work :( only bypass is ok, when i turn on my ocd is without reaction :( Enyone have a some pics or draws with right wires connection ? 3dpt, spdt, pots and jacks in/out ? Help please because i don't have any ideas what's wrong :(ReplyDelete
is it ok to use 1m lin in the gain pot insted of the log one?ReplyDelete
or even a 500 log is it possible? just cant get any 1meg ohm log..Delete
500kA will work, but give you less maximum gain.Delete
Still a good sounding pedal though.
My own OCD clone has a 500kA gain pot and 100kA volume.
I apologize if this was answered previously and I just don't quite understand but I have no idea where to wire the output jack. On V3 there's no wire labeled for output. And I'm kind of unclear as to what "Sw1a" and "Sw1b" is.ReplyDelete
Check the notes on the layout. Volume lug 2 is your output. Wire that to your switch like thisReplyDelete
Sw1 is the label for the tone switch in this layout. A and B are its 2 lugs. Connect the two wires to them respectively.
Thank you for clearing that up. Sorry if it was an obvious question, i'm new to this.Delete
Built V3 (based on suggestions above) and it fired up first time. Remarkably noise free even at max gain. Plays great with my strat SD bucker on the bridge for the hard rock stuff but can provide a wide blues bite on the neck SC too so very pleased. Not much use for me on the Low Peak setting. Darkens the tone and lowers the output which I end up compensating for anyway.ReplyDelete
Cheers for the layouts and comments lads!
I agree, the OCD blows chunks! I play in a band with someone that uses one, and it's brittle and plastic sounding. I hate it. Plus their guitar gets lost in the mix.ReplyDelete
http://i42.tinypic.com/nwazb.jpg The inside of my build
http://i42.tinypic.com/dvhhth.jpg Some cool tape I got at Lowes
http://i40.tinypic.com/2q82gyo.jpg An edge view of the tape
Just finished boxing up V3 as well. I love this pedal, it's deep but not muffled. It's thick and Ballzie. (sorry, ladies)
If you don't like the OCD, you must be on V4. This V3 is killer, IMO.
My best wiring job yet, but only because I went with a 125B enclosure. I just can't bring myself to build without leaving room for a battery, even though I use the power plug. I didn't have a 68n capacitor so I socketed it and put two caps in parallel to make it happen. Worked great. I'll swap in the real deal when it arrives next month. Also, I thought I would share this awesome tape I got at Lowes. It is like, 1mm thick and really sticky and pliable. It works great to keep your circuit from grounding out on the box. I also think I'll put a piece along the bottom wall and another along the bottom of the stomp switch to keep a battery from rattling around.
Great job, thanks for the picsDelete
Mojo your build looks solid, would you mind looking at my build I can't seem to get anything out of it with the pedal turned on. Thanks! I'd really appreciate itDelete
will build the version 3 :D...ReplyDelete
hopefully i can post sound review within 2 weeks...
Ive built the version 3, sounds neat.. theres only one thing, the spst switch seems have no changes made in effect tone...ReplyDelete
Errr....my switch definitely changed it from Hi gain to Lo gain just like the demos on youtube. You don't notice any difference at all?Delete
I've also built a ver3. Sounds great when plugged into my guitar/amp. BUT... When it's unplugged from the guitar with the effect still on I get a high pitched squeal that varies with the gain knob. Very annoying. I have no idea what I might have missed. Aside from that it plays and sounds great.ReplyDelete
Any ideas what might cause the squeal when its unplugged???
I had the same issue with my son of clay jones build. I upped the 51p cap between pins 1 and 2 of the opamp to 150p. This eradicated it completely - didn't affect the sound to my ears, except to get rid of the squeal. The OCD also has a small cap between pins 6 and 7 of the opamp - not sure if that one needs to be increased as well. Guess you could try the first one and see if that fixes it and then do the other if not.
If anyone is wondering why it matters if it squeals while unplugged, my SOCJ would also squeal if I moved to the bridge pickup only with the gain anywhere above 2:00 or so. Then it always squealed while unplugged. Other high gainers that I have built would not squeal like that while unplugged, so I just figured there was something amiss. Hope that helps.
Ok. I tried upping the 220p across pins 1+2. I had to up it to 1n for it to stop squealing. Except now i've lost much gain a bit of of volume. Totally confused... I understand what the change did. I just don't understanding why I just can't stick with the default values.ReplyDelete
I've noticed that there are two diodes that are a part of the original schematic. Any idea as to why these are missing in this layout?ReplyDelete
Sorry to be a pain... I'm just trying to understand what the differences here.
What opamp did you use? Are there any other component substitutions? Which schematic are you referring to?Delete
TL082CP. I've also tried JRC4558, OP2134A. Same result... All values for all of the other components are default. I can take pictures if i have too...Delete
I forgot to mention that this is Version 3.Delete
ehss I've got the same issue. did you ever find a solution?Delete
Hi would the v1 schematics work with 18v? is there a way to add a led?ReplyDelete
As long as your caps are rated for at least 25V then you're fine. Do you mean and an LED for indication? If so look at the Offboard link in the top menuDelete
Hello again everyone and sorry for asking the same thing, i can't find the v1 schematic around the net (i'm trying to PCB it), is there a direct link to it? thank you!ReplyDelete
I just finished this and I'm having a few issues. The sound is there and gain is good, however I get a loud pop when turning the pedal on and off, The volume knob gets louder for 70 percent of its rotation then the volume drops for a second and then it finishes going up, and finally there is a small volume drop in lp mode vs hp mode.ReplyDelete
I'm pretty sure the volume pot thing is just a bad pot, however the other two issues confuse me. Thanks for the help!
I cannot for the life of me get a build of VERSION 1 to work, I'd really appreciate anyone's input on this. I've tested most of the components on the whole board, replaced the IC, reflowed all the solder joints, checked for solder bridges, etc. Only get sound in bypass, can't get any sound with the pedal on, sometimes just a popping sound. Thanks!ReplyDelete
Measure the voltages between all the IC pins and ground, that will give us a good clueDelete
Awesome! Here's the IC voltages...Delete
PIN #1: 1.418, PIN #2: 1.25, PIN #3: 1.03, PIN #4: 0.1,
PIN #5: 9.28, PIN #6: 1.423 PIN #7:1.09, PIN #8: 1.286
Hoping this reveals something. Maybe PIN #4 needs to be resoldered?
IC numberings are like this, so I assume you have the right hand side the wrong way round:Delete
Your voltages on pins 1 to 3 and 5 to 7 all look low to me, check the value, placing and soldering of the 470K resistor.. You also shouldn't have any voltage on pin 4, but the 0.1 reading you're getting could just be the calibration of your DMM. It's certainly worth checking your soldering and the link though to make sure it is ok.
Built the V3 to spec and compared to an original V3. The tone is identical. There is a lot more volume in the original but still plenty past unity in my build so not an issue. Happy camper here.ReplyDelete
Hello I built the V3 version, but no soun at all (only in true by pass mode). I checked the placing, the soldering, the values...ReplyDelete
The IC voltages are:
1)- 1.35 8)- 8.88
2)- 1.33 7)- 8.33
3)- 0.937 6)- 8.21
4)- 0 5)- 0.23
IC is TL083CN
Thanks for helping.
Sorry, IC is TL082CN.Delete
Pins 1 - 3 and 5 are too low and 6 & 7 are too high. What voltage are you getting at the source of Q1? That is the row with the reference voltage on it which should be half supply and so around 4.5V. If you're not getting 4.5V check the value and soldering of the 10K resistor to ground and 10K resistor to pin 8. If you are getting around 4.5V then check your soldering for all components to the left of the board, reflow if necessary.Delete
Problem solved. Thank you very much!!Delete
I've just built a V3. It works OK and sounds excellent but I've got a problem - when I unplug input-cable there is a high frequency tone generated by the circuit. The pitch changes with gain control. It occours with 9V. I've tried 18V and problem's gone than. Any idea how to fix it to work on 9V? What could be problem in?ReplyDelete
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Hi friends!!!! I've this problem with my OCD v.1....ReplyDelete
Is it possible a mod in my ocd or I have to put a buffer after ocd?
In your opinion, could I solve with another volume pot value?
thanks in advantage, ;)
Changing the volume pot would also change the frequency response of the filter at the output of the OCD so personally I wouldn't do that with an original V1 OCD. You can make up an opamp buffer in 20 minutes and they can solve a multitude of impedance issues in an effect chain, so that would certainly be what I would look at doing first. I'd just make one in a little standalone box, then you can plug it into the chain anywhere.Delete
:) thanks Mark, which buffer do you suggest me?Delete
Personally I think they're functional things and so pretty much all the same to me. I'd just do a simple opamp buffer, probably a generic one from the datasheet like the JHS Little Black Buffer, but you've also got the Klon buffer too if you prefer. At the end of the day they all have a high impedance input, low impedance output, are unity gain and shouldn't colour the sound in any meaningful way. So take your pick :o)Delete
Ok I'll try one of these! thanks again!Delete
In your opinion, is it possible that the v4 could have not this problem?Delete
Possibly, but I have pedals with a similar output impedance which didn't sound as bad. It just was one of those pedals which did nothing for me at all.Delete
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No idea how I screwed this up, but holy crap... it's making insane synth noises. This is just the pedal as I adjust the Drive control! No guitar input. WOAHHReplyDelete
Hello sweet forum! :) built the v3 three times already, a very successful version indeed! is there any way to get just a bit more distortion out of it? say, 10-15%...? :DReplyDelete
Socket the 18K resistor and increase it until you get the gain you want out of it but be aware that this is a compromise and as the maximum gain increases, so does the minimum gain so it's case of selecting a value which works well at both ends of the gain pot.Delete
Alternatively you could use a 2M gain pot but that values isn't very common and it may be a bit too much gain. You could test that out though by putting a 1M resistor in the 18K sockets and see what you think at maximum gain.
Hi i'm bassist, great site! What's the most suitable version for a bass player of this pedal? I tried to make this version OCD v1 but i need more balanced sound. PLS help me to make the best choose...thanks...ReplyDelete
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Decrease the value of the Gain pot. 500K or even 250K may be better for you if you want lower maximum gainDelete
Sorry, removed my comment accidental.Here it is again.Delete
Hi,build OCD v3. Great pedal. Works fine. Is it possible to give it less gain. For me,even in the lowest setting, it has sometimes too much gain. Can I simple decrease the 18K resistor. And if yes, how much?
I dont want a lower maximum gain. I need a lower minimum gain.Delete
try decreasing the 18K resistor to a 2k2 or a 4K7.ReplyDelete
Hate to admit that I really love the OCD (v.1 and v.1 my favs) so when the Joyo Ultimate Drive appeared and people realized that it was a OCD 5 times cheaper, I was really happy to see Mr Fullshitone screwed :PReplyDelete
V1 and V3, I mean :PDelete
Yes I must admit every time I see an OCD clone like the Caveman hit the market, I get a nice warm feeling inside. Fuller is almost certainly my most disliked person in the industry, although there are a few close runners up :o)Delete
Javi, i think you mean Mr. Fooltone... :PDelete
Mike, Bill, Ed....the power-trio "Assholes Experience" :PDelete
Luckily, on the other hand, you can find people like David, Bjorn, Brian, Chad and many others that don't forget that they started building clones, and will even help you to build your clone :P
By the way, taking a look to these boards, if you want to add / correct, the filetring cap is 10nf and there's too a 100nf one in the filtering. I used to ommit too these little caps, but I've learnt that many times, are very useful to get rid og high pitch noises. In this very OCD circuit, you get noticeable less noise with the 10uf+100nf, than with a single 100uf, you can try it :)
Yes the good ones definitely outweigh the assholes, thank God for that!Delete
Fuller used to use a larger cap, and then swapped it for a 10uf + 100nf, but this is what he said about the caps used in the Fulldrive, so I don't know if he's also changed his philosophy back for the OCD:
"Back in the 90’s, I always used very large value capacitors (in the power section) because it was my opinion that they added a warmth and feel to the pedal.
Somewhere in the 2000’s, as I was re-laying out the PCB, an Electronic Engineer convinced me to drop those large caps down to 10uf and he added a tiny 100nf bypass cap, a trick used in many hi-end audio power supplies. Life moved on and I never directly compared an old FD2-Mos to a new one again UNTIL I pulled a bunch of old FD2’s out while researching for the Custom shop FullDrive3.
I noticed right away how the older ones were browner sounding and had a slight 'sag' to the feel, irrespective of whether they were Mosfet or non-Mosfet.
The only difference was in these power supply caps, and after a quick substitute of these for the larger value and a snip-snip of that little bypass cap and BINGO! There was that old FD2 sound…back again!"
But all the gut shots I can see of the earlier versions certainly appear to have the 10u cap and so I'm assuming also the 100n in parallel, so I've changed the layouts to reflect that. If Fuller opts for a larger cap in any further updated version of the pedal then I can alter it then. Cheers for the heads up matey
You're welcome, matey :)Delete
I'd like to recommend anyone interested in the OCD v.4 to try the Joyo UD. They will get the same tone, save tons of money, and more important, they'll piss off Mr. Foolshitone and prevent him to grab their money :P
I was wondering if anybody cold tell me whats wrong with my build. Everything else seems fine but the potentiometers are working the wrong way around?ReplyDelete
super simple fix. if they're working correctly, but they're backwards then you have revered lug 1 and lug 3. switch the wires and you should be good to go.Delete
What value of diode should i use for D1? TIAReplyDelete
You could try the usual suspects like a 1N4148, 1N4001 or a Ge diode like a 1N34 etc. Try socketing the diode and try a few different ones. But the OCD V4 is possibly the worst version, well it is the worst version, so you may not get a decent sound from it - as others have found out above.Delete
Thanks for your help dbat69, i will consider your comment about the OCD V4.Delete
Sorry guys, total noob here. Where does the 100uF cap go? What I have is two 10uF and one 100uF caps while all the three caps on the diagram are 10u. What should I do?ReplyDelete
Put the 100u where the top left hand 10u is on the layout, above the 33K resistor. They're power supply filter caps so if anything the 100u will do a better job, but that part was rejigged after the discussions above. They're filters for the power supply and so shouldn't make a significant difference to the sound from the audio components in the circuit.Delete
A 100u cap is usually used for a power filter cap. Looking at the layout this would be the top left hand cap which connects between the 100R and ground. So replace that one with the 100u. You could socket it until you get a 10u if you are concerned although I doubt it will make a difference to the soundDelete
Haa - you got in there before me MarkDelete
I see, thanks guys! I'm still learning :) slowlyDelete
Sorry guys, noob question again. Can I use this cap in the link below for the 100n cap on the layout? It says .1J100, not really sure what that means. Thanks again :)ReplyDelete
Yes, if i'm not wrong is a 100nf J (+-5%tolerance) 100 volts rated, so, no problem using it.Delete
Thanks so much man. I got this one and a metal film one (2A104J 100V), both are 100nF. Does it matter if I don't use the same type? Sorry for the noob questions again, I'm still learning really slowly.Delete
No problem mate. The original pedal is built with crappy / cheap components, so no problem using whateve you have at hand.Delete
Could someone tell me how exactly the wiring for the pots should be? Or where I should get some guide for that? I'm a complete noob and have no idea what I should do. Any help would be much appreciated. Thanks guys!ReplyDelete
The lugs you need to connect to are specified next to every wire shown and in the notes, and the lug designation on the pot is shown here:Delete
Thanks IvIark. Could someone please post a picture or something to show me how the DC socket should be wired properly? I've done everything but can't get any sound out of it, the only thing I could think of is the DC socket which I might have wired the wrong way. I've checked and checked and everything else seems to be right. I don't even know how to troubleshoot. Thanks again guys. Sorry I'm slow learner and this is new to me.ReplyDelete
Hello. From what I have read, is circulating version 1.7. Does anyone know what modifications have about 1.4 ?.ReplyDelete
Hi, I've made and love V3 and have added a wet/dry blend circuit so I can use it with my bass.ReplyDelete
However I'd like the tone pot to get quite a bit brighter. What would I need to change?
You could try lowering the value of the 47n cap at Tone 1, but to be honest it's a pretty crappy tone control and you're not going to get too much out of it. That will increase the upper cut off frequency though and so may help, but a lot depends on how much of the high end has already been removed prior to it in the circuit. Give it a try and see what you thinkDelete
Hi, just wondering what the 100nf cap from IC pin 8 is doing. I removed it and upped the value to 1uf but I really could not hear any difference.ReplyDelete
That's a parallel filter cap for the power supply, paired with 10µ. It has no tonal significance unless you use the circuit with a badly regulated power supply.Delete
hi, i made v3 and everything work fine, but there is a volume drop, unless i turn volume and drive all the way up. any solutions?ReplyDelete
the problem is that i cant any boost from pedal then it is on. how can i fix it?ReplyDelete
Can someone tell me - I built v3, sounds great but when the guitar is unplugged, the pedal makes high pitch oscillation when drive is turned past 1/3. When the guitar is plugged in, everything works just fine. So I was wondering.ReplyDelete
okay, I read the whole topic and I am not the only one... weirdDelete
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I built the V3 of this pedal and sounds good, except for when I turn the Gain knob towards noon and buzzing (ground hum??) is introduced into the sound. I've replaced, IC, used battery instead of PS, checked connections, razored between strips on board multiple times, etc.ReplyDelete
When there is nothing plugged into the input, there is a very high pitched (15Khz or more) squeal. Turning the gain and volume knob changes pitch slightly. Any Ideas on how to stop the squealing? I was looking at some schematics and saw that there are two diodes that are not included on this vero layout. especially the one from +9v to ground (some call for a 1N4148, another 1N34A before one of the transistors). Could the lack of this be introducing noise?? I got diodes on the way for another pedal I'm building so I'll give it a try... I'm kinda new at this stuff...so help please!
PS: Just Gotta say to keep up the good work, I am falling in love with building my own pedals, and without this site, i would be lost
UPDATE! So after looking at the schematic, I ended up putting a 1N4148 diode connecting at the 1st and 3rd rail (negative anode on 3rd) all the way to the right hand side by the 10uf capacitors and the noise is gone! This solved my noise issue, so this solution is worth a try if your having any humming/noise issues while the pedal is engaged.Delete
Any chance we could get a full schematic of V3? Searched and searched but can't find one that matches the vero layout.ReplyDelete
Thanks very much! Trudging through my own schematic, never thought to make separate V+ and V1 nets, really cleans up the layout.Delete
hey guys...still here...ReplyDelete
i made the circuit...it works ok but i need a little more mid...
what kind of modify do you suggest to add a little more mid to this circuit?
i made V3...
Hi Mark, Miro.ReplyDelete
I've a problem with v3.
The pedal sounds quite..right..
I think that there's something strange.
Something strange on pin 1?
I've this voltages:
Pins 1 to 3 and 5 to 7 are all higher than I would expect, but yes pin 1 is the most obvious problem. With that pin being right next to the supply pin and only separated by a track cut, are you sure that cut is complete and there are no burrs left in the hole that could be creating a small bridge across to pin 1?Delete
Ok, I'll check tonight.Thanks!Delete
Was a trace covered by the ink of the permanent maker :-)
All ok..thanks a lot..
The v3 is much better than the v4!
Thank you Mark!
Hey guys, new to building pedals and tried this one for the first. It's working on the true bypass, but it's not working at all with the effect turned on. The LED comes on, but no sound. Any help would be really appreciated!ReplyDelete
Pin 1- 8.78
Pin 2- 8.5
Pin 3- 4.7
Pin 4- 0
Pin 5- 8.22
Pin 6- Starts 5.5, then goes down to nothing after a minute or so
Pin 7- Same as pin 6
Pin 8- 8.97
Found that I had put the three capacitors in backwards...but still not changing my resultsDelete
Hi, I ordered the parts kit for the OCD v3 from MKlec and I recieved two 1M resistors. I only see one on the layout. Is there supposed to be two and if so, where does the second one go? Thanks - AndrewReplyDelete