Thursday, 28 May 2020

Schaller Tremolo


 
Short clip of Ian's build!
 

 

42 comments:

  1. Tag it, mate! Million thanks more. I'm heading now for the Coloursound Tremolo. Yeah, while the bastards don't arrive, I'm on a tremolo hunt. Cheers!

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  2. Forgot to point:no BC173 neither 109, so I used BC184, and it works nicely.

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    1. Oh man you are in a roll! I'll tag this one too!

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  3. I'm really interested to built this..
    I have lots of every other type of transistor... I'm wondering what the upshot would be if I was to put in bc108s?
    I guess I'll have to use sockets and experiment...

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  4. Also - I used to own the tuna melt and loved it! I see it uses a couple of opamps and an optocoupler....it was simple and sounded great

    If you ever fancy making a layout...😁

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  5. Oh no! I've built the world's quietest tremolo 🤦🏼‍♂️ (I tried bc108 and 2n222)

    I'll go again from scratch....

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    1. Which suffix has your BC108s? A, B or C?
      Youcan also try BC549 which is almost identical to BC109.

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  6. I'm not sure. they were around 330 which is the same as the 3 2n5088s I have.
    I have a 20k pot spare, so I may take a shot at the hearthrob...

    It's possible I just got in a pickle with the resistors.... because everything looked pretty clean!

    I'm on a mission to make my own tremolo and reverb and have a fully homemade board.

    Making the deep blue delays was truly inspiring

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  7. OK, so I just did a full rebuild of this (been waiting for some 2n5088s to arrive)
    And had exactly the same result. Everything works but it's whisper quiet..

    I even tried a new stomp switch.

    I can just about hear it working properly!

    The only original parts from the first build are the Jacks, led and toggle...

    Bypassed signal is fine...

    This one's a real mystery....

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  8. I'll change the switch tomorrow, but beyond that I'm all out of ideas

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    1. So the way that this works is that Q2 is just a simple boosting transistor. The two 47k resistors in the top right reduce the volume. The signal is connected to Q1, which is a switch. Everything else is basically an oscillator, and it just turns the switch on and off. When the switch is on, the signal goes to ground and disappears, when it is off, it's normal and it gets boosted like normal. If everything is working fine, I would say the problem is either signal is leaking off, or it's not getting boosted. Right off the top of my head, I would want to make sure Q2 is oriented correctly. If you had it flipped, I think the signal would get through, and it would be soft. If you want to take some pictures of the board I'd be happy to look at it and see if anything appears off. I traced a little of it and it seemed fine, and of course it was verified. At any rate, I'd say the problem is with Q2 if everything else seems like it's working. Also watch the pinout, 2n5088 and 2n2222 are reversed from the ones in the picture (which did match the bc108s I saw online). It's possible one or more are reversed.

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  9. Thank you... The 2n5088s are certainly reverses from the pic. I checked their pinout. Before soldering them in. Its so spooky to have built it twice and had the same result... Like I say the switch is the only original part. (and I can just about hear it's doing as it should)

    I'll take a pic. And see if I can make a Google photo link....

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  10. https://photos.app.goo.gl/F8romLa6jFyyrBd49

    https://photos.app.goo.gl/Yx8UPgywFeojDJAv9

    https://photos.app.goo.gl/xhUgc23HprFqtSf27

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    1. Are you able to send a picture of the flip side of the board? Don't worry, I am absolutely certain we can get this working

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    2. Yes....but I'm sure it's going into the bin 🤣

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    3. https://photos.app.goo.gl/5e12pmTZQvemaheRA


      And the Kay with the same issue (I've tried 2n5088, mpsa06g, and 2n2222

      https://photos.app.goo.gl/ieWArsANH4pSNw5Z7

      🤯🤦🏼‍♂️😭

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    4. Ian, I might be reading the picture wrong, but I think your foot switch might be wired incorrectly. I think you need to switch the blue and green wires.

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    5. Michael, I can see why you would think that... If you check the kay layout, the input and output are in opposite to usual dirtbox layouts. Rather than flip the board upside down I left it the right way up and took the wires round where they should go. they are crossed the back of the stomp switch. 👍👍

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    6. I'm looking at the Schaller... try switching your guitar and amp cables, I think it will work. I've looked at it again, and I'm pretty sure those wires on the foot switch need to be switched. If you look at your output jack on the right, the wire is tied to the middle left lug. When it switches one way, you go to the input (true bypass), when you switch the other way, it goes to the blue wire, which is the input of the circuit, not the output.

      It makes sense too if you think about it, the signal can still travel through the 470k negative feedback resistor, be affected by the tremolo, and then be reduced further by the input resistors. I would expect it to work but be very faint.

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    7. When I say switch the cables, I mean plug your guitar into your output side, and your amp into the input side. I bet it works.

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    8. I double checked the switch wiring it's all fine. I'm pretty much at the stage now where I can do it with my eyes shut 🤣
      Out of curiosity I did what you said but it's definitely wired right

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    9. Skreddy wiring has the middle lug of the footswitch going to the circuit input, but you've got the middle lug going to the output. Regardless though, if you switched input and output and it still didn't work, there must be something else amiss. My next step would be to check continuity and voltages with a multimeter. I would want to know that the voltages on each of Q1 look reasonable, and I would be checking to make sure that everything is connected and there are no shorts. Everything looks fine, but that's really the only way to find where an error would be. I feel like the odds of it being a component are low, since it happened to you twice. Each attempt had different components, right? You didn't reuse capacitors and resistors? I really think the issue has to be around Q1.

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  11. I’m pretty sure a BC109’s pin out is the other way around. If memory serves me correctly. So possibly the layout might be incorrect in that respect. You might need to flip your trannies. Maybe someone else can confirm before you get out your scalpel. I always use little pin header sockets so I can screw around with trans orientation and make quick swaps. Just a tip for future headaches.

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    1. I've followed the cbe reference...ill,swap the toggle later and see if anything happens

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  12. https://photos.app.goo.gl/jUjWiyBBSwrT3X3p8

    A short video of the issue I'm having.
    I think this one's getting to me because I can hear what a potentially great tremolo it could be

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  13. Just built the Kay with the same results!🤯🤯🤯🤯

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  14. The switch wiring looks wonky. Try this way. I use it almost always. Hope it helps. http://guitarpedalbuilders.blogspot.com/p/blog-page.html?m=1

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  15. I'm gonna have a third go at this....I really want one! It's interesting that the input and output are on the opposite sides to usual... fuzzhead - would you be kind enough to take a quick glance before I go again?🙏
    I'd be elated to get it going 🎉🎉🎉

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    1. Fingers crossed that your third go will result in success.
      The layout itself is definitely working as is since both me and Dragao have verified it.
      Regarding inputs and outputs of a circuit...it doesn't matter which side of the board the pads is located, it just happened to be the opposite for this layout to get a nice "flow" and keep the layout compact.

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    2. Brilliant that's good to know. I'll be checking each component value carefully as I go.

      👍👍👍

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  16. What do you think is my safest bet, transistor-wise? I've found bc109c, bc549, bc173, and bc173c....
    I'm tempted by the 549s because they are not in a metal can and in my experience the plastic top ones always seem to be more consistent....

    I'll gladly take any advice here.

    👍

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    1. All your transistors are good candidates for this. Does yyour BC549 have a suffix. If it is "C" it is almost identical to your BC109Cs, just a fifferent cap. I went with BC109Cs in my build.

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  17. When I say 'found' I meant to buy...I'm gonna get bc109cs! Thank you!

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  18. Hi Ian, its hard to see but is your top right input resistor 4K7 (should be 47K). Good luck

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    1. I'm gonna double/triple check things like this on the next build 🤞🤞

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  19. Good luck mate, Ive built plenty of things 2 and 3 times also

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  20. Ahaaaaa!!!! It's up and running! And I squeezed it into a smaller box!
    Sounds great!

    https://photos.app.goo.gl/hSAUz6yWoS85TgMk9

    https://photos.app.goo.gl/kTsw7oN9RzNT3C428

    Thank you Anders 🎉🎉🎉

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    1. Finally! :-D
      Your demo video have been added.

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    2. 🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉🎉

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  21. https://youtu.be/IRvPpFD543w

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  22. Anders....I'm going to band practice tonight with a pedal board entirely made up from dirtbox layouts!

    Naga viper, distortion plus, big muff, blue delay, Schaller tremolo, and 3verb.

    Thank you😊😊😊😊

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  23. This is a lovely trem. Would be nice to have the Markm Hearthrob version too (hint ;-)).

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