Sunday, 25 July 2010

ZVex Super Hard On


This is the newer version of the Super Hard on with a zener diode, and is based on Zach's published schematic.



REDDIT UPDATE: Nothing fishy about it, it was the schematic Zach published for the Inventobox and can be seen here: http://www.zvex.com/module_instructions.pdf

182 comments:

  1. I've been wondering. What software do you use to draw these layouts?

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  2. I use the Java version of this:
    http://diy-fever.com/software/

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  3. Do you have a good source for 5k rev pots? I've been looking. Thanks!

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  4. Ben, Mammoth electronics. They definitely have them in stock.

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  5. just built this, sounds amazing! great driving the front of an amp. lots more boost than the Fat Boost, but that one sounds saggy and power amp-y, fat, so it's great in a different way. half way between a boost and a drive. think I got my 5KC from Small Bear in the US. thanks for making all these sweet layouts

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  6. just a question. The first cap on your drawing is a 100nF and on the zvex site its a 0.01uF which is 10nF. Will 10nF work as I have just ordered a pack of 10nF.
    Thanks

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  7. Every schematic I've seen for the SHO has had a 100n for the input cap with the exception of Zach's PDF, but I would certainly expect his own schematic to carry some weight. The only thing I would say is that the SHO can sound quite glassy and even brittle with some amps anyway, and using a lower value input cap will reduce a lot more bass getting into the circuit. Personally for that reason I'd keep using a 100n cap and if anything I'd probably go up in value rather than down. But it's a quick change so maybe it's worth just trying both and seeing which you prefer. Certainly I would say that if you've ordered the 10n then try it and if you're happy with how it sounds with your gear then your own ears carry more weight than anything.

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  8. Yeah i think I'll breadboard it. I might also try swapping the 10M resistors with 1M, I read somewhere that that is possible.

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  9. Yes that will lower the input impedance which may also take a bit of top end off it. It's worth experimenting with those, and maybe also the output capacitor, to tailor it to your gear.

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  10. hi there, i'm beginning to get into building pedals and heard the sho was a good place to start. I'm using mammoth for all the parts. so here's my big newbie question: for the capacitors, how do I know what voltage and material type to buy based on the schematic? thanks!

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  11. For all my layouts I'd tend to use multilayer ceramic for anything up to 1nF (and so for all the pF values), polyester for 1nF to 1uF and anything above 1uF I'd use electrolytic or tantalum. So for these I'd use a polyester cap for the 100nF and electrolytic of tantalums for the 10uF and 47uF. As long as they fit physically into the board, then pretty much any manufacturer will be good.

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  12. Hi IvIark,
    Thanks so much for all the great veros! I built a regular SHO and just finished a super duper 2 in 1 version. Now I have a couple questions. If I play hard with both channels engaged all the way up on the super duper (with the volume turned down!) it will cut out for a second when I play loudly. Does this mean the zener is letting current flow from the input of the second channel to ground? ie: the output of the first SHO when played very loudly is at least 9.1 V?

    Also, there is a pretty audible click when switching on/off. Especially when I switch both channels at the same time. Any ideas on how to make the switching a little smoother?

    Thanks a lot,
    Matt

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  13. ps: my switch wiring right now is the normal true bypass using 3pdt switch and led.

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  14. The zener is used to protect the mosfet from static. I don't know about your problem with cut outs, maybe a poor ground connection somewhere? A lot of these effects can pop with true bypass switching, so you could try a 1M pulldown resistor from input to ground. If you haven't got room for it on the vero you could even solder the resistor straight from the board input lug to a ground lug directly on the stomp switch.

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  15. What 9.1v zener diode do you use in the schematic? Is it a 1N4739A or B2XC9v1?

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  16. Aha! I found in an old thread where in designing the super duper 2 in 1 he ran into the same problem and solved it by changing the frequency response:

    Zachary Vex wrote:
    "just in case anyone's wondering, the super-duper 2-in-1 has two super hard-ons inside of it. the second one has a master volume control that replaces the tie-down output resistor in a standard super hard-on, but when that master is turned up all the way, both channels are precisely the same as a super hard-on.

    okay, that's a lie. there is one teeny-tiny difference. the super hard-on's input frequency response is 0.3 Hz to 100kHz. i was forced to limit the super duper's frequency response to 3Hz-100kHz because when i left all that near-DC response in there, the unit would nearly shut down and go silent for half a second with both gains cranked all the way if you hit a hard chord. but what's a couple of Hertz between friends?"

    What can I do to change the input frequency response? I am assuming that I should change the input capacitor to a lower value. Is that right? Does 10uF sound right?

    Thanks very much.

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  17. Here's my mini SHO from the updated layout - crazy amounts of gain in a very little box :)

    http://i177.photobucket.com/albums/w212/79silverburst/Pedals%20and%20Stuff/DSC01241.jpg

    http://i177.photobucket.com/albums/w212/79silverburst/Pedals%20and%20Stuff/DSC01244.jpg

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  18. I built this using a 10k linear pot and wired it in reverse as i couldnt find a 5k rev pot on the day i decided to build it.

    with the 10k pot its great you get quite a large amount of a clean boost before any of the gain kicks in!

    Thanks for an excellent layout

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  19. That's great, thanks for the info. It's always good to hear how some alternative parts/values work

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  20. And fx40b, thanks very much for the pics. I missed your post somehow

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  21. Hi Ivlark
    Thanks for these Ive built this & its great, housed it with your purple plexi
    One little problem though , It's got a hiss when its turned on even with the volume at zero any ideas? thanks in advance

    Ive also a small prob with the pp But Ive posted on that to save confusion
    Thanks again

    Turkey

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  22. I've built this loads of times now and never had any hiss so I'm not sure what the problem could be. Have you tried swapping the mosfet?

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  23. Thats It! swapped the bs 170 & its working perfectly...
    Thanks your a genius
    Carry on the good work
    Great site btw!

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  24. so... if i replace the 100k resistor with a 100k pot wired as a variable resistor will that give me a master volume?

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  25. Is the Zener in your picture of the build oriented the right way? I thought the black stripe went to ground.

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    1. Yes it's correct, cathode to gate

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    2. No idea what's wrong with my build. Checked everything a hundred times. I wonder if the transistors got screwed up or the Zener. I had the positive and negative switched when I first built it. You think that would have damaged them?

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    3. Mosfets are susceptible to static damage (which is the reason for the zener in the first place) so it's always a possibility. I always use PCB header pins as sockets for transistors so it's easy to swap if anything does go wrong.

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    4. I'm an idiot. Found my stupid mistake. Used a 10r instead of a 10M. Really need to start checking the bands instead of what I labeled them months ago.
      Quick question, I have 12v zeners, will that be ok instead of the 9.1v or is that a no no.

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  26. Ha ha, we've all done it! 12V will be fine

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  27. Thanks so much for the help. You're the man. Awesome layouts btw.

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  28. Help!

    I don't get unity gain? at minimal settings I still get a substantial volume increase and can't for the life of me work out why?

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    Replies
    1. Can you take a high res pic and post the link here, I'll see if anything stands out to me.

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  29. Ok, here it is, sorry if it's too much of a mess to see... 1st build an all that :)

    http://s1170.photobucket.com/albums/r534/vince371/

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    1. Well it certainly looks right to the layout (assuming the values of the resistors you can't see are correct). Melx's layout is also correct for the first version of the SHO, except R2 and R4 were 10M not 1M5. The smaller resistors would lower the input impedance but I don't think it would push the pedal past unity, but you could always try the bigger resistors if you have them. Apart from that, maybe swap the BS170 because they are susceptible to static and may be damaged, and reflow the solder to make sure there is a good contact.

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    2. I really don't know :( .... Just tried The meathead and that flunked too.. Had me tearing my hair out for 6 hrs...

      Don't think I can get my head round it all... gutted :(

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    3. Don't give up. One day it'll all click into place and you'll be knocking out a pedal a day. With the Meathead lots of people have problems with it and it's usually because of the transistor pinouts. Again post a pic in the Meathead thread (front and back preferably) and I'll see if I can see anything. Also mention in the thread which transistors you used.

      Sometimes you can be tearing your hair out and a single component failure will be causing all the issues, with that in mind you should measure every component before soldering them to make sure they're all good. It's really worth investing in a good multimeter that can also measure capacitance, it can save a lot of heart ache and wasted time and you can get them cheaply enough from eBay. Also consider buying some of these:

      http://www.ebay.co.uk/itm/370538646607

      Not a lot of money but extremely useful. I use them to socket every transistor in all my builds for a couple of reasons. Firstly you never have to apply heat to the transistor and so you never run the risk of heat damage. And secondly it's easy to swap them if you're fault finding or just want to try different transistors to choose your favourites in the circuit.

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    4. Thanks for the info... I've dismantled the meathead now... I had it working (not in an enclosure). Then for some reason the LED wouldn't light so I started tinkering with it and I open a can of worms ... I get really confused with where ground, in/ output wires go... anyway It ended up with no LED and a massive volume boost and the volume pot acted like a tone pot??. I even built the circuit from scratch with exactly the same results so I give up :(

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    5. Ok, back.... I can't let it beat me l0l!! I had it working once and can't leave it alone!

      Ok, I have taken the switch out and just wired the circuit with the in/out jacks and power.. It works (kind of) The volume still acts a kind of tone pot, at minimal settings I get a big volume boost and rolled off highs and when turned fully clockwise I get the 'normal' sound? I have changed pots, same result. I have made two circuits, both with the same results? really has baffled me?

      Common sense would suggest that a component has failed, but on both circuits? I may replace the transistors on one tomorrow.. my brain is too fried right now.. started at 11am finished at 9pm!

      I have enclosed a pic of front and back

      http://s1170.photobucket.com/albums/r534/vince371/Meathead/

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  30. I've continued this on the Meathead thread Vince:

    http://tagboardeffects.blogspot.com/2010/10/dam-meathead.html

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  31. Just built this... works like a charm...1st time too! ;-) don't know what went wrong with the last one but this layout worked perfectly for me

    Great pedal too

    Cheers

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  32. Am I missing something, or is the layout of the components in the photo inconsistent with the graphic (namely the upper right hand corner)? Don't see any jumpers either, but they could be obscured.

    Question - would swapping out the 100nf cap with a 47nf cap result in a brighter overall sound as I suspect?

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    1. The photo shows a build I did using a millennium bypass daughterboard for the switching which you can see at the bottom of the pic, and so the 2K2 LED resistor wasn't required. The links are there, one can be seen on the right hand side of the output cap, the other is obscured by the same cap because it's leaning to the left slightly.

      And yes a smaller input cap should reduce the bass.

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  33. I seem to be getting quite a bit off popping when turning on/off? I've wired the switch to the Skreddy way..

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    1. There isn't a lot of room to put it on the board laid out as it is, so if you've used the Skreddy method to wire the switch then add a pulldown resistor straight to it, like this:

      http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Pulldownresistor-Skreddyswitch.png

      That should help

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  34. Nice one Mark.. I've seen some say it can take some of the sparkle away but i'll try it and see... it's not a big issue, I just like to learn about stuff. I found this also that explains the popping... sounds like it's just a nature of the beast.

    http://zvex.com/vex_SHO_instruct.pdf

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  35. Hi! I'm just starting with reading schematics (and building them), so I have some beginner questions.

    The input and output, are those the tips of the guitar cables? And does the sleeves of the jacks go to ground?

    The schematic says LED+ve. What's that? LED I get but ve? And I presume it goes to ground then?

    And what about bypass switch? Or is the ve that?

    Thank you, and I'm sorry for my major lack of knowledge..

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    Replies
    1. Yes input and outputs are the tips, all sleeves are connected to ground. The schematic says LED+ve because from the supply rail it goes through a 2K2 current limiting resistor and then out to the LED anode. The LED cathode then connects to the switch which grounds it when the effect is switched on. This may be helpful:

      http://tagboardeffects.blogspot.com/2012/02/offboard-wiring.html

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  36. Also, I can't find any 9v1 Zener diodes at Mammoth electronics. Could someone link maybe?

    Thanks!

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    Replies
    1. http://www.mammothelectronics.com/1N4007-1-0-Amp-Silicon-Rectifier-p/120-1013.htm

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    2. Thank you so much for your help! I will get back when something happens with the build.

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  37. Hi Ivlark! Amazing site you have really sparked my desire to build my first pedal. I have spent some time learning how to read schematics and working on my soldering technique. I think I am ready to order parts for my first project the SHO you have here the only thing I can't see to wrap my head around is what voltage or watt value I should be purchasing for these projects. Any direction would be greatly appreciated

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    1. Thanks for your comments. I use 1/4w resistors the vast majority of the time. I do have a set of 1/8w as well which are perfectly adequate for these effects, but I only really use them in tight builds, or particularly when the resistor only spans 3 rows because using the 1/8w resistors means that it can still lie flat on the board. I also have some bigger 1/2w and even 1w resistors but they are too cumbersome for most builds really except maybe using tagboards. The thing I like about 1/4w is that you can have them in consecutive vero holes and the bodies will still sit comfortably next to each other, anything bigger and they are overlapping each other and so don't lie straight which could impede other surrounding components. The resistors shown in my layouts are always based on the physical size of the 1/4w MF25 resistors and so should give an accurate representation of what the final build will look like if you use that type. Depending on what sort of quantities you want to buy in, you can get a set of 2500 1/4w metal film resistors from sellers like sunpec on eBay for about £11 and they will keep you going for a long time.

      For caps it really depends on whether the effect is running at 9V or higher. Polyester and ceramic caps are usually rated at 50V+ so you're fine with those types, but electrolytics can be rated much lower to keep the physical size down, so for 9V effects I'd suggest at least 16V caps, and for 18V effects you want to be using 25V caps minimum. You can get a good cheap selection of ceramic, mylar and electrolytic caps from Futurlec if you search for their Value Packs. Or plenty can be found on eBay at good prices.

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  38. I'm done! It works and sounds great! Thank you for all your help!!!

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    Replies
    1. Excellent, you'll now be officially hooked on DIY. Expect to spend hundreds on parts very soon! :o)

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  39. hello, the sho works but I have a problem with hissing when I activate the effect. I think it comes from BS170. Is what I could replace it with another mosfet? And if so, what else can I use?
    thank you very much

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    Replies
    1. You could also use a 2N7000 but it would need rotating 180 degrees.

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  40. Could you explain the LED+ve in the layout? I don't see it on the picture or know what it is

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    1. Yes, that connects to the anode of the LED. The cathode then goes through the switch to ground. It just saves you having an LED current limiting resistor somewhere offboard.

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    2. Oh and it's not on that photo because I used a millennium bypass daughterboard for that build, so the LED and resistor was dealt with by that board on the switch.

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  41. Unless I'm mistaken, the 100k resistor can be replaced with a pot/trimmer to control overall volume. My question is, is there a trimmer that can be mounted on the board in place of the resistor that would fit and you could recommend?

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  42. Is that right? As I wouldn't mind adding a volume pot to mine so I don't have to lower my amp to compensate the boost in volume?

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    1. Yes, that's exactly what Zack does with the second side of the Super Duper. You can add a final volume control to anything in this way if you have an effect that you think needs a little taming.

      It would be awkward to fit a trimmer to this board laid out as it is, but I could do another layout with a volume trimmer if anyone wants it.

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    2. Having built a few with this layout, I was wondering if you knew of any parts that would fit and do the trick with this layout specifically.

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    3. There just isn't the room in the layout as is. The trimmer will need to connect to ground, and there is no available hole on the ground rail. If you have to use this layout, or you want to do it with an existing pedal then you'll either need to use an external volume pot, or maybe make up a little external volume trimmer daughterboard like this:

      http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Volumetrimmerdaughterboard.png

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    4. Great, that would make my SHO perfect. So I would take two wires, one from each end of where the 10k is/was and feed them to which lugs on the volume? and would I need to ground the volume?

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    5. Take out the 100K, output to volume 3, volume 2 to output, volume 1 to ground

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    6. Thanks man - with the seemingly billions of electronics parts available in almost every conceivable size/configuration, I thought you might be aware of some tiny trimmer that would do the trick.

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    7. I've got some trimmers with a short wiper lug but with very long outer lugs and those would fit across just about any spans. But the problem is that one of the outer lugs needs attaching to ground, and there's no free space on the ground rail. So without the layout being rejigged it just has nowhere to make that connection.

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    8. Excellent, cheers mate... How do you think B5K's Reverse linears.

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    9. ..Would work in this?. Though I'd finish my sentence.

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    10. Not sure what you mean mate, for the volume control? There's no such thing as reverse linear :o)

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  43. Sorry, should of been clearer..I meant for the boost. no such thing? what do you make of these then? listing error maybe.. And leave at least 10 for me if you buy any! lol

    http://www.ebay.co.uk/itm/10x-B5K-Potentiometer-Pots-Reverse-Linear-Taper-Rotary-Shaft-3-pins-5K-Ohms-/270962227352?pt=LH_DefaultDomain_0&hash=item3f169b7898#ht_3511wt_954

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    1. Ahh it looks like they're just 5k linear... just saw 10 x 5k reverse for £2.35 and got over excited!... C5k's are a real pain to get :-(

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    2. Futurlec do them but they have slightly longer shafts to the normal lin and log pots:

      http://www.futurlec.com/PotRot.shtml

      Or you could always make your own reverse log pot. Just as an experiment (ideally on a breadboard if you've got one) use a 50K linear pot and put a 6k2 resistor between lugs 2 and 3. Then use your multimeter to check the value through the rotation. It won't have a precise reverse log sweep but it should be better than linear.

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    3. Nice one Mark, I'll bear that in mind and try it one day... Thanks for the link :o)

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  44. This comment has been removed by the author.

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  45. Replies
    1. They're cuts in the tracks; You can use a small drill bit to do those.

      like this;

      http://www.google.co.uk/imgres?hl=en&safe=off&gbv=2&biw=1280&bih=687&tbm=isch&tbnid=UcZKcTEMaaVCHM:&imgrefurl=http://www.zen22142.zen.co.uk/Prac/vero_circ/vero.htm&docid=-S50mHWo1_8u4M&imgurl=http://www.zen22142.zen.co.uk/Prac/vero_circ/14.jpg&w=599&h=373&ei=FFLFT9rqJYWe0QXc8s1U&zoom=1&iact=hc&vpx=188&vpy=344&dur=561&hovh=177&hovw=285&tx=142&ty=72&sig=109568494953653060737&page=1&tbnh=155&tbnw=220&start=0&ndsp=16&ved=1t:429,r:6,s:0,i:82

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  46. This didn't respond well by adding a volume pot in place of the 100k resistor. Boost at min, volume at max you get a whine and below unity. You have to nudge the boost up to about 9am for unity then the whine stops.

    Just a heads up if anyone tries it.

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    Replies
    1. That 100K doesn't seem to be in the signal path, but it forms a filter with that 10µF cap.

      If one would want traditional volume control in addition to boost, one should take the output wire to new volume pot's lug 3, use 2 as new output and connect 1 to grounds.

      Actually. This would be quite interesting and useful little mod. Very good idea indeed. With this, one could have the ice cold cracking super boosted tone without blowing the fuse on the next pedal/amp/anything on the line by attenuating the output with such a simple measure!

      Might try this, once i get back to my desk..
      +m

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    2. That's the way I wired Mirosol. I'm going to try it on another board as I suspect It may be a component fault.

      Thats what I was thinking, it saves having to adjust your amp the compensate the boost :o)

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    3. My suspicions were correct... new board works like a charm. I won't be making them any other way now. VERY handy having the volume on the pedal...volume on max and boost at minimum gives unity.

      Fantastic on the dirt channel ;o)

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    4. Just trying this myself now and having the same problem as Vince mentioned - a whine while the pedal is bypassed that goes from gain at 0 to about 12:00, changing pitch through that sweep, and disappears beyond that. Pedal engaged sounds fine and the pot seems to do the trick as far as level control.

      I used mirosol's decription above as well as this image of Mark's from elsewhere in this thread (where he recommends putting this pot in place of a 100k resistor in the circuit, contrary to miro's remarks - which way is correct?).

      The only thing I can think of that might be causing this is the empty connections now on the switch where the effect output and output jack were formerly wired. Should there be connections on one or both of those lugs?

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  47. This question is coming from somewhat of an amateur, but what is the purpose of the 47uf cap? I built this pedal based off the posted diagram, but used a 100 uf cap in that position instead since that's what I had. And the pedal seems to work fine. What difference would changing this value make?

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    Replies
    1. That cap is a power supply filter cap. Increasing the value to 100uf shouldn't make a difference. If you were to use, say a 10uf cap in that slot, there's a possibility the effect may be a bit noisier.

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  48. Just built this..works, but super noisy--hum no matter what, even when gain at 0 and with no guitar plugged in. Bad ground or perhaps a bad transistor? I tried 2 different bs170s but maybe they were both bad.

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    Replies
    1. It is highly unlikely that you have two bad components... Solder bridge or bad joint would be my first guesses - as the first usual suspects.
      +m

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    2. I too had noise and was tearing my hair out all weekend over this one! I had a loud hum that changed frequency as I turned the pot. I checked the soldering swapped the transistors and even made a second build. When I was rechecking I placed it after another pedal that was sharing the same 9 v power supply but in bypass, and the hum disappeared. When I removed the first pedal the hum came back. It worked well with a standard boss or Ibanez wall wart adapter. So I guess this is very sensitive to the power supply being used. Works great with a battery too. I'll rewire the 3pdt so that it can take a battery. I like this one a lot, as the man said, it works great on weak pickups. Thanks again for a great site. Any more thoughts on this or how I should check my power supply (it's an Eagletone Ps 12)?....

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  49. hi mark, mind if i ask, how do you connect this layout to the volume trimmer daughterboard that's on the link in one of your comments?
    http://i76.photobucket.com/albums/j6/IvIark_2006/DIY/Volumetrimmerdaughterboard.png
    do you omit the 100k resistor on the main layout altogether, or do you replace it with a jumper? and does the blue output wire on main layout goes to the "output from effect" on the daughterboard?

    thank you.

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    Replies
    1. Yes remove the 100K (and you can remove the link between the 100n and 10u as well). And yes, output wire from the board goes to "Output from effect" on the daughterboard.

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  50. Hi IvIark
    But if you want to put a volume pot?
    Where it connects?
    regards

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    Replies
    1. I'm sure this has been discussed above. Remove the 100K resistor, take the output of the board to Volume 3, Volume 2 to output, Volume 1 to ground. The volume pot will be 100K.

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    2. change the resistance of 100k for a jumper?

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    3. Nope, I would have said if you'd needed to do anything else

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  51. I don't have a 5k reverse log pot in my toolkit, but read somewhere that you can bridge the wiper and ground on a 100k linear pot, to create a 5k log pot.

    I couldn't fully understand how to do this. If you are feeling charitable, please clue me in to how this kind of thing works--specifically what resistor value to turn a 100k linear into 5k log.

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  52. Start with a 100K linear pot, and put a 5.2K resistor between lugs 2 and 3. That will give you around a 4.94K pot with something like a reverse log taper.

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    Replies
    1. Thank you so much! I hope I someday understand the underlying reasoning for why this works ;-)

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  53. Help: how do I adapt the LED +ve wire to work with the Offboard wiring instructions? I have soldered the board and prepared the enclosure.

    Here is a photo of my build and the docs: http://imgur.com/KrJ37

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  54. Shit. Built this, but effect doesn't work. The LED and bypass work fine, but effect doesn't. Have tried 3 different BS170 transistors.

    I did use a 10K linear pot and a high-intensity LED. Is there any chance that the LED draws too much current?

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    Replies
    1. No, the circuit will draw whatever current it needs from the battery or power supply so the LED is fine. If the circuit isn't working you either have a faulty or incorrect value component(s) or there's a fault in the build. You're going to have to do some close up checks for unwanted solder bridges, make sure all the values are correct, check voltages you're getting at the mosfet pins etc.

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    2. Will do, Mark! I don't know much about how to test MOSFET voltages, so will have to read up.

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    3. Just measure the DC voltage between each pin and ground.

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  55. This pedal doesn't need a switch..always on!!And these harmonics....wow

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  56. Hi there...
    pic and scematics looks different..which one is wrong?
    the schematics is a 12x9 with a cut and a link that seems missing on the photo build tha is a 13x9
    Thanx i love your work!!!

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    Replies
    1. I just used a vero offcut that I had to hand which just happened to be 13 columns wide, if you look on the left hand side there's a spare column. Only other difference is I didn't include the LED current limiting resistor because I used a millennium bypass daughter board which included the LED resistor.

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  57. I want to add a master volume control but I'm confused as to the difference between your (mark's) method of removing the 100k resistor and replacing it with a 100k pot and the other method mirosol suggested, which was to keep the circuit as is and put a new volume pot after the output. What are the benefits of each?
    Also, What value pot would you use for mirosol's method?
    Lastly, if I'm going to do mark's method but I only have a 50k pot, can I wire a 50k resistor in series with it to give it a total of 100k? I would guess that this would limit the volume from being able to go all the way quiet because you won't be able to vary the resistance all the way from 100-0, but that might not matter since I don't think I would need it to go all the way down in volume, just tame it a little.
    Thanks!

    ReplyDelete
  58. Boxing day's boxings part 1:
    http://mirosol.kapsi.fi/varasto/boxes/FR+SH.JPG

    Fuzzrong to master volume modded SHO. For a friend.
    +m

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  59. All of my zener 9v1 diodes are testing at approximately 7.4v

    Is this a problem?

    ReplyDelete
  60. Built two of these today, including one on a Hammond 1590A micro-enclosure:

    http://imgur.com/DWUet

    ReplyDelete
  61. Replies
    1. Nice job, thanks for the pics

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    2. Wow, thank YOU, Mark (& Mirosol)! Everything I know about this hobby, thus far, I learned here; this website is a godsend.

      I don't know if you ever wonder how folks wind up here, but. . . until a few months ago, I was spending $1,000+/month on boutique and vintage pedals, when I had two packages opened and the pedals stolen off my doorstep. I got so irritated that I couldn't safely receive pedals at my house that I decided to start making my own. That evening, I stumbled across this site, read Mirosol's guides to components, and started ordering fuck-tons of pedal parts--which no thief is going to take ;-)

      And, now when I order a finished pedal, it will be because I personally know it's a good design, and the builder is a decent guy (or Devi Ever). Definitely buying some Fairfield Circuitry boxes; Guillaume is awesome.

      Anyway, a serious thank you to you guys. I am still mostly clueless, but having a ball making shit and getting better!

      Delete
    3. Yes that's exactly why I started too! The last pedal I bought was in 2008 (Moollon Chorus which I still have and is very nice) and I honestly can't see me ever spending like I used to on stompboxes again. Much better to take a pedal you like and fine tune it for your own tastes and to suit your own gear, then it isn't just good, it's perfect.

      I do like to support the builders I like, so I bought a Timmy, Zendrive, and Skreddy Pink Flesh amongst others, but I won't waste money anymore buying the latest Fuzz Face or Tubescreamer from someone who thinks I should part with £250 because they use silver solder and 24mm pots.

      I'll still buy things that can't be easily recreated with analog electronics (I do love Eventide), but for dirt boxes and the like just give me a soldering iron every time.

      Delete
  62. Nice, just out of curiosity, why did you socket all the in and out wires to the vero?

    ReplyDelete
    Replies
    1. I love socketing all wires, so I can pull the board to debug on my prototyping board.

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  63. Very nice indeed. That's tiny. Also, did you just stick the wires in the sockets or did you solder them in?

    ReplyDelete
    Replies
    1. They are stuck in snugly. After I have played for a few days, I open the box and put a drop of solder on each.

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  64. One more thing: I adore BitchesLoveMySwitches.com for enclosure parts. That guy ships like lightning and is dirt-cheap. He is also super-responsive to email.

    Go check his site. I love ordering from Lawrence and hope more folks find their way to his site.

    ReplyDelete
  65. any ideas for eliminating the switch popping? I've added a 1m resistor from board input to ground and that improved it nominally. Then I removed the LED indicator from the switch and no improvement. I did leave the Led connected to the vero board just removed it from the switch so it wouldn't come on. Unit sounds great but the pop is frustrating

    ReplyDelete
    Replies
    1. It may be a leaky cap, maybe start swapping them until you find the culprit

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  66. I got the whole thing put together, but when I plug in, I get a very muted sound. I can hear the crackle when I turn the knob, but nothing. I have used a 5K Linear and 5k Audio because I can't find a 5k reverse and I don't really want to wait to order one. My LED doesn't even come on!!! I am using a 3pdt toggle switch instead of stomp switch. That shouldn't matter, should it? I tried wired it the offboard way on this site and then rewired it the gaussmarkov way, but still only muted sound. Does it matter which leg of the LED is soldered to the switch? Sorry for the stream of thoughts! I'm frustrated and my wife is tired of me talking about it!!

    ReplyDelete
    Replies
    1. If the LED doesn't even fire then something isn't right. The board connects to the LED anode, cathode to the switch. You really need to test any build before you add the switch though, or you're adding another potential point of failure that you have to check.

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    2. Ok. I got it working and put together. I had some shoddy soldering when I wired up the enclosure and switch. Sounds awesome and it's a ton of fun. I'll be making a tubescreamer next, I just don't know which one. Thanks so much! This site is awesome!

      Delete
  67. With all the boost pedals I've done, this one gave the best result..totally worth it!
    With all of them though, I get hum on the sound. More as I turn the knob. Hum that doesn't exist on the originals . Is it something that has to do with the wiring?

    ReplyDelete
  68. Built it into a BB enclosure with a Red Llama clone. I did the master volume mod and it doesn't seem that useful IMO.
    Really happy to push my Red Llama clone with it, thought. Maybe I'll try to swap it out for another boost circuit... Something with less high end, as the Red Llama is already pretty ear piercing (in a very positive way).

    Thank you for everything!

    ReplyDelete
  69. I've got a problem with my build. I've got signal passing through the circuit, and the crackle is indeed OK. When my pot is fully clockwise (all the way up) I get a boosted, some added dirt, signal that sounds pretty good. When the knob is turned back down (counter-clockwise), I get an aweful squelch, feedback, oscillation even, type sound. This isnt the crackle from the pot, its continuous.

    I dont currently have an LED connected, but I didnt think this could cause this.

    Any thoughts?

    ReplyDelete
    Replies
    1. I had the same problem, it was the transistor. Try one with bias approximately 4.5-5v.The one you use now has probably less volts than it should

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  70. how can I tell the polarity of a capacitor that you have used a non-polarized version of. like the 10uf and 100nf in this schematic? which direction will be the long lead?

    ReplyDelete
    Replies
    1. There's a negative sign on the negative side of the electrolytic caps. Are you really going to use a polarised 100nF cap? If so the negative leg is attached to the input wire

      Delete
    2. Ok, thanks. There are also some on the Mosferatu schematic I couldn't figure out. Like the 470n caps. I only have polarized caps in that value (Tantalums).

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  71. Hey up. I've just put this together but something's noquite right. Anyone fancy checking a picture of my circuit if I email it to them?sound comes through on bypass but no guitar on when engaged.
    it does crackle though. probably simple fault.

    ReplyDelete
    Replies
    1. Upload the images to tinypic and post the links and I'll have a look

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    2. [IMG]http://i49.tinypic.com/33uwz7s.jpg[/IMG]

      Try that, was logged into wrong user earlier was on the band account. Hope you can spot what i've done wrong. Ta

      Delete
    3. The mosfet and the diode are the wrong way round

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    4. tar that explains a lot then...

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  72. Hey IvLark. my circuit doesn't work. can i email you a pic of my layout and you can take a look?

    ReplyDelete
    Replies
    1. Upload it to tinypic or similar then post the link here. Then you'll have more than one person checking over it for you

      Delete
    2. [IMG]http://i87.photobucket.com/albums/k153/heavysoul77/photo-1_zps2f71684b.jpg[/IMG]

      Delete
  73. Hey,
    Please help me figure out if I'm going crazy. I cannot for the life of me see where I've gone wrong. I've checked for solder bridges and bad joints with a continuity tester and even double checked by scoring the tracks with a knife.

    When on I get no sound whatsoever. Could the transistor be broken?!

    http://tinypic.com/r/289j7eu/5

    ReplyDelete
    Replies
    1. Mosfets are very prone to damage from static electricity, which is why the diode is used in the layout, as static protection. So it could be that there has been some damage to it. Are you sure the cuts are in the right place?

      Measure the voltages between all the BS170 pins and ground to see if that gives a clue, but it may be that the mosfet simply needs swapping. PCB headers are always recommended to use to mount transistors so you don't have to solder them in, and can quickly swap them in instances like this.

      Delete
    2. Thanks for the speedy reply. I'm getting absolutely nothing from all the pins on the bs170 - I guess that really is broken then, that is providing I'm not using my voltmeter incorrectly @_@ the battery is reading around 8V.

      .... another ps - I'm using a really old bashed around analogue voltmeter so it's a little in accurate, bit the needle is definitely not moving when touched to the bs170

      Delete
    3. Just made it to the shops in time before it closed after work. Got a few more bs170s, and used some header pins as suggested. It works now. I even had some pins lying around should have just used them.

      Anyway, thanks.

      Now, any ideas what to do with the other bs170s I have? I'm thinking maybe a buffer/preamp stage for a piezo pickup, as I have one that could do with one but, any pedal suggestions are welcome!

      Delete
    4. Glad you got it sorted. ZVex Box of Rock, Catalinbread Rah, Skreddy Top Fuel, Lovepedal Super 6 all use the BS170.

      Delete
  74. ps. - thanks for all the other layouts, they've been great!

    ReplyDelete
  75. Howdy all!

    So I have a newb question about sourcing the parts...namely the caps.

    Would these types of caps work in this build?
    http://www.mammothelectronics.com/16-Volt-Nichicon-Electrolytic-Capacitors-p/301-gp-16v.htm

    What's the difference in all the voltages?

    This is going to be my first build and I'm pretty confident in actually building the pedal but sourcing the correct parts is probably my weakest link.

    ReplyDelete
    Replies
    1. Yes those caps will be fine. Basically the voltage rating of the caps is dependent on what voltage you're supplying the effect with. So as you'll be supplying this with 9V then you'll be fine with 16V caps. If it's an effect that you intend to use with an 18V supply then you would be better choosing 25V caps to make sure they are rated higher than the voltage you will be putting into the pedal.

      It's only really an issue with electrolytic or tantalum caps, because most ceramic and polyester will be rated at least 50V, and you won't be putting anything like the full supply voltage through most of the caps in the board anyway, but it's just a case of erring on the side of caution.

      Delete
    2. Thanks so much! I'm really excited to start building pedals. And I must say I've learned a lot over the past few days/weeks from your site. So glad I found it!

      Delete
  76. One more question...

    I see that there is a ( - ) on the 10uf cap, but can't tell where the negative side is for the 100uf and 47uf caps. Is there a right or wrong way to put electrolytic caps?

    ReplyDelete
  77. Got a question - wired this up, sounds great. The only issue I have, is that the pot does nothing?
    Why could this be?

    Thanks in advance!

    ReplyDelete
    Replies
    1. If you used a linear pot, all the action happens in maybe the last 10% of the pot rotation. If you're not getting anything at all in any position then did you forget to ground lugs 1 and 2? If you did make that connection are you sure the joint is sound?

      Delete
    2. I used a rev 5k pot and actually used the older 'compact layout' you did - it's tripping me out because it's probably something stupidly simple?

      Delete
  78. Made this today. All seems to be functioning just fine - but it seems to be very dark sounding. When up full its actually muddy. I thought if anything it would be brighter. I have made sure all components are correct with correct values. Could this be caused by off board wiring errors? Its the only thing I can think of.

    ReplyDelete
  79. Hi. Is it possible for someone to make a pcb layout ready to transfer on board? It would help me a lot, but I don't know how to do it myself. Thanks in advance

    ReplyDelete
    Replies
    1. http://elkit.web.id/2011/04/zvex-super-hard-on-boost/

      there you go

      Delete
  80. hello, If I use a 12v supply, may I replace de 9.1 zener diode by a higher value like 12v/1.3w???

    Thank you all

    ReplyDelete
    Replies
    1. No you can leave the zener 9V. That's just used for protection against static electricity and so doesn't have to match the supply voltage.

      Delete
  81. This comment has been removed by the author.

    ReplyDelete
    Replies
    1. Dom,
      You can use any type of capacitors, they need not be axial. You can use that daughter board for the switch. Just move the 2k2 resistor to the clr spot on the daughter board instead of the main circuit. Leave the LED+ve wire off.

      To wire it for a battery, you will need to add a stereo jack to the input. the ring connector gets the battery ground.
      On the power socket there are two positive connectors. The one for the battery gets lifted when a power supply is plugged in. General Guitar Gadgets has a bunch of good wiring schemes.Check out one of their drawings for the power set up. https://www.generalguitargadgets.com/tech-pages/51-switching-and-wiring/33-many-bypass-switching-options

      Delete
    2. This comment has been removed by the author.

      Delete
  82. This comment has been removed by the author.

    ReplyDelete
    Replies
    1. If you're getting continuity between input and output jacks in both positions of the stomp, then you must have a faulty switch or created an unwanted bridge which is permanently connecting them with your soldering.

      Delete
    2. This comment has been removed by the author.

      Delete
    3. This comment has been removed by the author.

      Delete
  83. This comment has been removed by the author.

    ReplyDelete
  84. Hey there. I've looked through the previous comments to see if anyone else has had the same problem, but I did not see any. I believe everything is soldered correctly and in the right place, but I'm getting problems when hooking it up to my guitar. The pedal only makes a very faint signal when the C5K pot is turned fully counterclockwise. Turning the pot clockwise only serves to remove any guitar signal. Could the pot be busted?

    ReplyDelete
  85. Hi, I'm having a real hard time trying to find a 5K reverse log pot... Somehow 500K reverse are available here, but I'm guessing it's too much :D Are there any replacement options? Does linear or normal log sound bad or something?

    ReplyDelete
  86. Hi,

    I start my first build. I have do it on a breadboard for testing and it doesn t work. No sound when is on, The led and The true bypass is ok.

    Can somebody give me The voltage on The bs170 and on Some other pin?

    Thank s for your help, great blog and community.
    Nicolas

    ReplyDelete
    Replies
    1. Maybe someone see somethink wrong i have no sound ( if i connect in on out it s ok)

      http://s22.postimg.org/71fctrk81/20151123_221535.jpg

      http://s9.postimg.org/4uyet1rrj/20151123_221527.jpg

      Thank's for your help
      Nicolas

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    2. Maybe someone see somethink wrong i have no sound ( if i connect in on out it s ok)

      http://s22.postimg.org/71fctrk81/20151123_221535.jpg

      http://s9.postimg.org/4uyet1rrj/20151123_221527.jpg

      Thank's for your help
      Nicolas

      Delete
  87. Yes it was Just that.

    Thank's you very much for your help.

    Again great community

    ReplyDelete
  88. I've built this ovne before, and it worked great.
    Now that I want to build it again, I open up my Zvex SHO, and saw two more transistors on the PCB, anybody know what they do?

    ReplyDelete
  89. i had 2 bs170s broken in my sho. ive put the sho after some high gain pedal on maximum volume. can the other pedals fired the bs170s? is there any way to protect them?

    ReplyDelete
  90. Am I the only one to notice all the differences in the diagrams and pictures?
    The vero layout shows 5 resistors but the photo of the circuit board in the pedal has only 4.
    The circuit diagram shows 4 resisters but it also shows 2 diodes.
    The vero layout has lost the diode from the gate to +ve.
    Finally, where did the 4.7u across +ve & -ve come from? Its not in any circuit I've seen.

    ReplyDelete
  91. There have been different versions of the Super Hard On made by Zvex. The part that changed is the static discharge protection for the MOSFET. There is a version with two silicon diodes and a version with one Zener diode.

    The fifth resistor in this is a current limiting resistor for the LED.

    The 47uf cap from +9V to ground is meant to smooth out ripple current in the power supply. The original did not need this because it was powered with a battery only. If you want to use a daisy chain you may want to include that cap, but you can omit the cap if you want.

    ReplyDelete
  92. Hi, I'm getting a perfectly working Sho on a battery but when I'm running from a power supply I get an awful hum! I have the 47 cap in and I'm using two diodes as per the standard schematic, would a single Zennor diode fix this? If so what is the code number I need? Thank you. Dan

    ReplyDelete
  93. Hi, I built one of these and the effect doesn't work. There's no sound at either extreme of the pot and only some hiss in between. My transistor voltages are (DGS): 9.44, 0, 0.
    I've checked for shorts, tranny orientation, etc but I can't figure it out. Any help would be greatly appreciated!

    ReplyDelete
    Replies
    1. Well, I just replaced the BS170 with a 2n7000 after reading that mosfets are easily damaged by static (I checked the pinout), and now the gain pot crackles all the way through and still no guitar sound.

      Delete
    2. The MOSFET is then functioning perfectly, if you hear the crackle. Now your issue must be that the signal does not reach the gate. Triple check the input cap (connected to the input wire) and then probe it to see where the signal dies.

      http://diy-fever.com/misc/audio-probe/
      +m

      Delete