Can i replace the 1N4001 with something like a 1N4004 or 1N4007? So i'm not sure. Problem for me was thin sounding pedal. Volume and Tone seem to be working but all the Distortion pot does is turn the pedal into a really shitty frequency generator :( I'm going to put it to one side until i don't feel like destroying it and then i'll post pin voltages for the opamp and JFET. This comment has been removed by the author. Too fuzzy and tuby but like overdrive it is the best. Or use 1N34A germanium diodes to make it YouDirtyRat. http://www.diystompboxes.com/smfforum/index.php?topic=96351.0. I followed the original Rat schematic, so I added the 1nF between the two wires Gain 1 and Gain 2 & 3, but it is just a bit attenuated. Strat and marshall amp at high volumes for example. !I have a problem with opening the BOM file . it won't load at all .. Can it help? I m grateful!Kind regards :). No typo. what you could do is take the rat 2 layout as it is and put sockets in place of the resistors and swap them to be like the original, or it gives you the ability to try different values and see what you like. I was able to get the perf working. Just finished this build and all i get is low farty sounds. I havetryed different mods on the rat, build a new one strict to the classicrat schematics and can't find out why this pedal schould be somethingspecial. Into what amp? i looked those sites and didn't see the schematic for the rat 2. now, there could be different versions of the rat 2, and have slightly different values for certain areas. It can be used, but not as is. the PDF says 47 or 100 ohm, i had 47 available so thats what i used, any chance i killed something else on the circuit?? What is the difference under the hood between these two pedals. quick question, does the resistor change for turbo version apply to dirty rat too or is that 2m2? The circuit was the same the rat uses for the last buffer, G:1M to groung/S:10k to ground / D:9V . Where do I wire up the two red link in this PCBhttp://beavisaudio.com/projects/FKR/images/MightierMouse.gifThank You, I made few rats. Hope that helps. Hi, I've just build this board, but got several problem at first. Sounds like it's mis-biased. I flipped R11 and R13 due to not reading this thread before making the pedal. I'm not entirely sure why I included it *head scratch, Thanks man it just seemed strange as it wasnt in any of the typea! Call it good. ITT and 4 Was the only letters written on them. They're not reflected in the diagram. (Skipped 15nf because I couldn't find one at the time) I'm not sure how much gain this has taken away from the pedal but it still sounds fat with a fuzzy-ish gain (LM308). You need a negative ground one. Hi, it does'nt work for me. Is there no mistake in potentiometer Filter? Sounds good on a Vox type amp. I know this post is ancient. Thanks for the schematics. It will fit in an original ProCo enclosure, you'll just need to wire at least 2 of the pots off-board. I used to have a "stereo" Cool Cat chorus pedal, but Danelectro's idea of "stereo" was to have one clean channel out and one dirty channel out. On this layout I did the Original and a RAT2 and both were rockin! All you have to do is download the file and print. For volume ad filter I used b500k with 33k resistor from lug 1 to 3. No one has noticed that the 560R and 47R should be swapped around to be correct to the original pedal. Incidentally, which is your favorite version? Try replacing it. I thought it might be a bad pot so I replaced it with one I tested and still the same. Just remove D1 & D2, take a wire from where one side of D1 (or D2) to a switch (pin2) and another wire from where the other end of the diode was to the switch (pin 5).Place your diode choices across pins 1 and 4, and 3 and 6 for a DPDT switch and hey presto.Use this link for an examplehttp://tagboardeffects.blogspot.co.uk/2014/05/blakemore-effects-rous.html. The Si-Ge/Si-Ge is weak in volume. If you used Ge diodes you would have a smoother, more compressed distortion and less output. http://www.analog.com/static/imported-files/data_sheets/OP07.pdfhttp://www.ti.com/lit/ds/symlink/lm308-n.pdfOP07 is not pin to pin equivalent with LM308. when i built my rat, i altered those resistors to help make it better suited for bass, but by doing this i also altered the gain.about that 1n cap. Again, new to the DIY so trying to locate quality components I can order all together and not have to piece it all together through five different places. Was going to start with the original. The BlueLED blinks fine when selected and I like the sound. Has anyone found a solution? I had some really great results. Even I made the spice simulation. I also did a 1K pots Ruetz mod. You might have killed D1 as well. The stereo output of the DOD chorus is very nice, and very well distrubuted across both outputs. It sounds great, but my distortion control is working as volume control. After noon, its acting almost like a glitched out Fuzz when there is a hard attack on the strings and it cuts out the first millisecond then it rings out. All components are on the same side of the board (non-copper side). Here's the basic schematic: Trademarks are the property of their respective owners. Update on this one: It's working after all. You could swap the pot for 50K or even smaller to make more usable.+m. Thank you for the input. Hi there im just starting this build but the bom lists r10 as 1.5k but I can't find r10 on the layout? R11 and R13 though are not. Luckily I socketed the fet and opamp. Please help, Anyone. When I use run amp, it's still the last pedal in the chain. is there a difference between lm308n and lm308 ? Hi all,I've just built this one and it works fine. I've made some changes and somehow improves playability and tone. Many of these have been posted on freestompboxes.org, so check that site out for great discussions on building your own effect pedals. I usually use an old Randall SS amp into a couple of Jaguar 12 inch speakers. I feel like I have the most versatile RAT pedal ever! One of the things I've noticed with this build on perf board is the proximity of the tone knob to the gain knob can cause an issue with volume of the pedal. I am using the OP07 Opamp if that helps, also I have tried more than one opamp with no difference, tried different JFET's and checked their orientation and run a knife between the tracks. What can be done to solve this? by ggbb 15 Oct 2019, 17:05, Post Seems to be cutting to much treble. Thanks Zach your are right about BAT, actually is a big cristal germanium diode with only 41 number writen, (bigger than clasin 1n60).there is no cap in pin 3 and 4 I saw on several schematics from Rat 2 and the older ones, seems to be an standard, also I saw the JHS mod that changes the cap between pin 3 & 4 from 1n to 10n. by nooneknows 13 Oct 2019, 12:58, Post Or put heat shrink wrap on the adjacent lugs of the tone and gain pots and then solder the connections topside. } Is it right that 1 and 2 foot is connected on the layout? If you're looking at the same schematic I just did, there's a 1nF cap from pin 3 to ground, which is what pin 4 goes to as well. Not 100% sure on the filter thou. The only exception is the pots if you decide to go with board mounted onesthey need to be mounted from the solder-side of the board. The distortion sounds great when set correctly, and since I built this for personal use, I kinda like having the option of pushing it into crazy mode. Greatest sound ever, but, was such a hot signal, any other pedals I used (Chorus, Flange, Phase) were too noisy. Check FET orientation, are you using an alternative op amp? A friend once owned a Vintage RAT (1991 reissue) that had BAT41s stock. Just in case the jfet are not able or hard to find. ProCo - You Dirty Rat - exactly, which diodes. This is one of those versatile builds that could be useful for a number of different tasks. The pot lugs/legs go the empty pads below the labels at the top of the board (lug 2 is implied). I havent boxed it yet..will it go away if i box it? This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I got a question, where to wire toggle switch from the board for clipping, if you want to make a switch for multiple clipping, remove D1 and D2 and put two cables from toggle. There should be an additional 1n cap to ground between the 100k resistor and pin three on the IC. The one going from input to ground (the one on the left) is just a pulldown resistor, so that won't make a big difference. Powered by. Hello Cody.I'm going to build the RAT2. Swap them and see if that helps. I had to do this too. The 22nF is the input cap, the 100pF is a lowpass for the distortion and cuts off the high end of the distortion smoothing/softening the clipping making it less harsh. I solved problem with Wampler euphoria so good that I can use rat sometimes with small amount of gain. I don't think a static resistor will solve your problem here. I need to replace my original board. This maybe the cause of the squeeling some people have noted when nothing is plugged into the input. could you help me ? Also, I assume the switch will be in the General Layout notes? I can't figure out where is the problem. Thanks guys. Check out the Transfer Image Library page for pre-scaled PDFs of every PCB transfer image on the site. Replacing it with an OP07 did the trick. Are any resistor value in series to make it closer to a 100kA.thanks. LM308s are widely available through ebay and the prices are not that bad either.+m, Cheers for setting me right miro. HI. Should be fine, but I'm not sure if it'd affect the tone. I'm not aware of BAT41 being used in YDR - but it wouldn't surprise me (and I haven't really spent time trying to validate YDR diodes). No help please? Sounds like you're using a positive ground psu. It has to do with some people liking vanilla ice cream, and others liking strawberry. folder. I got the squeal that somebody else got. (Test point: between source pin and 10k resistor. The component names from the above schematic follow those in the layout drawing below. I also put in switch for clipping selection, 1-RedLED/RedLED; 2-BlueLED/Zenr-Zener; 3-Si-Ge/Si-Ge.The RedLED/RedLED is not lit when I use it but has sound. I did the v2, but the volume was extremely low. My stock YDR has CDSH270 schottky diodes. This is just a little change in the schematic. Does a mix of 1n270 and 1n914 sounds good for you? Can pots be put in line. i know there is a lot of sonic differences between the rat and rat 2, so the things you're seeing could be the reasons. However, the layout as depicted above is missing a component (if you examine closely the RAT 2 schematic and actual units). One question on the resistor change. I believe there was a period when the VR and the Deucetone or YDR were both in production - however this was probably around 2002-2004 which was a few years after the manufacture date of my firend's VR. If you did, R11 and R13 are shown in the wrong order. The normal rat uses 1n4148 or simalar (0,7V) and theturbo rat uses LEDs (2,2V forward voltage). Was I wrong? I went back through it tonight, everything checks out, I even compared it to the last build I did. Try the other one. why?). If you use a 308 and still get the squealing try putting a buffered pedal in the chain. No, it's an original ProCo Rat that I got in 1987Chorus last? I'd leave one board mounted just so the board isn't floating. I have a Rat II, and I've used a Vintage Rat, and both of them had output comparable to my other pedals. I lean more towards the Original myself. usually layouts don't get verified if there's something wrong with them, so i would say it's same to assume it shouldn't be there. I incoroporated this into my build by extending the width of the layout by one column. I might take the pots off and test them to see if that's the problem, check R11 and R13, they are in different places on two schematics. i went with 1n914's ..it was the 2N4148 that threw me off. It's usuable, a bit harsh, but not very versatile. There are some simple mods and you can build in a switch to changebetween turbo and normal rat. (fixed clipping info accordingly). Maby it's the same hype like the klon pedal ortubescreamer that I can't understand. by nooneknows 28 Oct 2019, 22:19, Post Given the chance, I cannot even start telling you how great your work is. More towards the middle of the board? I really have to pound the strings to get anything to come through as it cuts out after a short ruing out. So, yes, a clean SS amp :). The circuit shows no sign of Volume gain until about 3 o'clock on the volume pot, but the main problem is that when I turn up the Distortion I get a really high pitched squeal which lowers in frequency the more the Distortion pot is turned up. There s also a 1n cap missing between IC pin 3 and ground, as James Nettleton and a few others noticed. It's just a high frequency roll off. Works great for me. Since the LM308 compensation pins are used for offset nulling on OP07, your behavior is expected. You do amazing work here! mine is squealing in a insane way, when the cable is unplugged. great work you do here man with the layouts. Now, there is only couple of small changes to the output buffer and volume control when compared to the original Rat. Thanks. document.execCommand('copy'); I just like it. Btw cap for pin 3 and 4 makes a good small improvement. Which one gets changed? Check that you've got the right values, especially for R4, and R11-13. Build in the classic LM383 or other OP(socket!). I bulit this last week, sounds good, but a lack of taste to me, I made a few mods, LM308 Metal can, D1 and D2 replaced woth BAT41 Ge diodes (sounds powerfull and I have too much overdirve/distortions with 4148) remove 47R to 1K pot (sweet spot there to find fine tune, and 560R one leg lifted to on/off swich. You Are right. Are you sure it's verified? Great, it's finally working. I only got 10kA and 500kA potentiometer in hand. you dirty rat is with germanium! Absolutely. I'd still recommend getting the correct chip as the Rat won't sound like a Rat without LM308.+m. There are two 2.2m's on the board. top notch. . Copyright 2022 All rights reserved. please any one can share pin voltages????? I check and recheck but there doesn't seem to be any mistake. Built it and all functions work. I'll check my values. Did Anyone build the Rat with another IC like TL071 or similar ? not connected on both ends).Thanks for the design! The main difference between the normal RAT and Turbo Rat are theclipping diodes. Goes really well with a VOX amp and humbuckers.http://fuzzquest.blogspot.com/2012/11/the-flying-rat.htmlGreat layout Mirosol, highly recommended build. So that was fixed. Just skimming through the comments, i think ill try to add the cap between leg 3 of the IC and ground also to see if this helps. Nice one mate. Interesting I wonder what those diodes are then. I used the OP07, 2n5457 and a 1.5K instead of a 1.6K from the filter pot. It will not be a direct replacement for the original board. I checked for solder bridges, what super obvious thing am I missing? And while i m at it, you might want to use a larger value for that cap in case you are facing lots of noise, at the expense of reducing the gain :), Yes, had to use a 22nf :( Now I can max gain though :). Nice distortion. For this project, the board can be used to make 4 different versions of this great distortion box: The original RAT, the RAT 2, the Turbo RAT, and the You Dirty RAT. on most RAt 2 schemes seems that 2.2M from the left is replaced with 1M, I will try that change as well to low as 220k. It still fits very comfortably into a 125B.I also added a switch that toggles between yellow diffuse LEDs and the stock silicon clipping diodes and I'm glad I did, because I prefer the LEDs.Finally, I implemented the "Lube" mod from Beavis Audio and put the 560r resistor on an on/off switch.All mods highly recommended. I haven't found any schematics showing it any other way Swapping the resistor values would give you a 721Hz and 129Hz pair of low pass filters instead of 1539Hz and 60Hz - and this filters the input to the opamp (see here : http://www.electrosmash.com/proco-rat). I will admit that I've not used them like you do - the last pedal in my chain is always my DOD chorus - it puts out very nice true stereo, and I sometimes run it into two amps. on the face front or on the back ?and where should i put all the rest of the components ?is the IC is on the front and the rest on the back ?Thanks Sir, you are a great person to shared this. document.querySelector("#clickCopyString").addEventListener("click", clickCopyString); A forum devoted to mod, tips and suggestions for upgrading and rehousing your VERY CHEAP commercial stompbox to near boutique excellence. There is no straight on replacement for LM308, so to get your circuit working right, you'll need LM308 chip. Do i jump it? but experiment and see what happens. I use A250k for gain at the end of my experiments with rat. Now I have spent time playing the pedal and it sounds good until I get the distortion past noon. The other one from vref rail to 1K resistor.+m. What's a good source for quality bulk resistors and capacitors, etc.? They may have used BAT41s somewhere else in Pro Co (they make other things besides RATs) - who knows. Any idea what could be up? thanks for the great job !there's a tiny mistake, the filter pot is supposed to work backward, so lug 2 should be tied to lug3 instead of lug1.keep doin' what you do mate (y)Rafik. If I low the guitar volume the pitch of the squeal change, even with the Distortion pot of the circuit. Thing is such a beast. Did anyone experience the same / found a solution? This thing sounds great. right placement is on the right schematic, yeah, I did checked that, both R11 and R13 are on the correct placement (the image on the right)R11 (1M) is on top of r13 (10k), I want to add the overdrive mod. If I turn the gain up any higher than 1/3 of the way, it starts to squeal, feedback, and oscillate. Also there is a weird phasing sound in the ring out. Enjoy the builds and please also visit us on, Dimitri's build blog, recommended reading for anyone wanting a DIY walkthrough, Parasitstudio.se - Freppo's blog Parasit Studio. The higher of those is practically almost identical to the Ruetz mod with the 1K potentiometer set somewhere halfway (see here in the 1k potentiometer section : http://www.diyguitaramp.com/rat.html) thus making the rat much more of a gentleman and I m not sure that this is the sound that most people expect to hear, at least at the start :) I d be interested to hear your opinion on those above, and please contribute any sources if available! It looks like my LM308 was faulty or something. Played with this some more. Had to put a 22nf cap from pin-3 of chip to ground. Use sockets and try out some different diodes. Just don't forget to add a 1n bleeder cap.I've tried a lot of variations and my favorite is leaving out the 10K to ground resistor right before the volume pot and using 1n5817 for the clipping diodes. hello. Thanks a lot for any help! We could not be m Not all these layouts are verified and some are put together from unverified schematics. Here's a collection of vero (stripboard) and tagboard guitar and bass effect layouts that we have put together covering many classic and popular effects in growing numbers. I use a daisy chained power supply, so for things I build for myself I r From Schematic to Stripboard September 2012 http://tagboardeffects.blogspot.com Updated 23rd September 2012 A lot of people have asked A number of people have asked me to do a build guide for one of these effects, but I noticed the other day that one of the guys here (timmy) From the source: The Hizumitas was designed for the one and only guitar sorceress, Wata, from the legendary band, Boris! Are there any aftermarket mods for these pedals? Also the old pedals use the now called Millennium bypassthat uses a normal cheap switch to get a full bypass. I believe this was probably a production mistake caused by mixed up parts (those BAT41s looked exactly like your typical 1N4148 - glass DO-35 and even share the text label "41" in a single line on the body), as opposed to a deliberate substitution because they ran out of 1N4148. const body = document.querySelector('body'); Also can anyone tell me the cap between pin 3 & 4 What exactly does? const area = document.createElement('textarea'); I guess you can verify it. Just don't populate it. I can't figure it out. But, I use a Boss Overdrive these daysIt's more of a distortion though. I then tried a 1M pot, and it goes up to around 300k, but then back down to 0 again, acting almost like a balance pot. Did anybody assemble on this layout? Now I have little different sound but with more bass. Not clean SS, I'm betting. no problem buddy. Many of these have been posted on freestompboxes.org, so check that site out for great discussions on building your own effect pedals. In the latest one he decided for a Si + LED combo, but my personal favourite is the Si + Ge combo. The rat is such a great pedal!! I live in the States. Also, try using a linear pot for the volume pot, Right Got me some LM308 opamps and stuck one in, and it's acting exactly the same as it was with the OP07. A bit like the Fuzz Factory effect.More problem with humbuckers.I built a pair of the modded version from Sabrotone without any issue, now I wanted a stock version, but this layout seems a bit tricky. The pots can go from 0 to 100k. As mentioned above, the filter pot has been reversed and I find it more inuitive than the orginial rat.But, if I'm correct, if the filter pot has been reversed, its value should be C100K instead of A100K. As far as the cap, I don't see one between pins 3&4, there's one at pin 2 down to gain 2&3 which is 100pF, and a red one that's 22nF. area.value = '2022-08-02-04-02-50-344'; One more step! Only way I could get rid of the squealing when gain gets to noon. adding 1nf to ic pin 3 to ground will remove whistle noise. Hi. Enjoy the builds and please also visit us on Facebook and Twitter. I measured the 100k pot to 8k max when connected to the cirquit. Also it is worth to play with the clipping section in the basic Rat layout, as that can really give you different tonality. (Simulatiomng b200k)And distortion a100kUsed ua741 instead of lm308 Didnt add compunsation cap 30pf.When i turn distortion i get lot of noise. So if you have good luck, or bad luck for that matter, then please let me know by dropping a comment in the topic. https://i.imgur.com/F4BgTRC.pngHere's an updated layout that reflects the mistakes pointed out in this thread:-Swapped the 2.2uF and 4.7uF around (top left)-Added 1nF between IC pin 3 and ground-Replaced the 10uF connected to the JFET's source with a 1uF-Replaced the 1.6k in the Filter section with a 1.5k (negligible). I did some troubleshooting and found that noise was just a poor ground solder on the volume pot. tried 2 more 9v psu's, with the same result, R1 keeps burning. you can put a socket in that area for that cap, and see how it sounds with and without it. :)+m. Yup. Not seeing them on the schematic or layout. This means that the turbo rat has a higher output and less compressionthan the normal rat. =), i must be horribly missing something but where is the component values? There's differences in the 2 layouts above as far as component labeling:C6C7R7R82x R9Which diagram do I use, the one on the top left or top right (the same as the one in the attached link with the component list)? I use C250K (don't have C100K right now) ans the course of the pot is more progressive than with a A250K (dont't have A100K either). Any ideas?Thanks again! Powered by, Here's a collection of vero (stripboard) and tagboard guitar and bass effect layouts that we have put together covering many classic and popular effects in growing numbers. Got this built up at the moment on the bench, whats the deal with R12?