Thursday 21 September 2017

18v Colorsound Power Boost

Well as usual just finished a round of exams, so it's time to start posting the layouts I did when I was taking study breaks. This time I'm going to space them out so there's not a sudden flood.

First up the 18v Colorsound Power Boost. Same topography as the Colorsound Overdriver, but ran at 18V, and to my ears boarders on a fuzz. I made 4 different layouts, 2 identical to the original (early & late version), and 2 that have an added master volume pot. On the original the pot labeled volume is really more of a gain pot then a true volume pot, so I figured that it would be much more usable to be able to max the gain and control the output level. The original came with BC184L transistors, but you should be able to use any NPN Silicon Transistor.


Original Early:


Early Version with a Volume Pot Mod:


Original Late:


Late Version with a Volume Pot Mod:





42 comments:

  1. Hi Zach hope the exams went well! The layout states 3 links is that a typo? I take it all the electro caps need to be rated 25v+? Thanks pal.

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    1. So far so good. Yea I had 3 before and ended up being able to remove one. I'll fix that. Also, 25v caps would be fine. As long as the max voltage of the caps is higher than the power going in you're good to go.

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  2. I tried the Early version w/ Vol pot: I'm getting signal through, but the output is pretty low until the last 10% of Gain/vol is cranked. Even then, it isn't boosting above unity all too much. Also, the Bass and Treble controls don't seem to have any effect. I've gone all the typical troubleshooting routes, and triple checked my components and their placements. I'm pulling my hair out on this one.

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    1. hey man. i finally had time to look over the layouts and go over them again. i found a bunch of errors and corrected the layouts. they should be good to go now.

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  4. Unfortunately, I already build the incorrect version that didn't work. I'll have to comment back once I've tried the new layout, but I was wondering if there is a big difference between the 9v and 18v versions? I wanted to build this pedal, but use a 3PDT on/on switch in-between the board and a charge pump to be able to switch between 18 or 9 volts. I already have other 9 volt BP's made too, and am wondering if I could do the same with them. I figure you get more break up / earlier with the 9 volt, but more headroom and what not running at 18 volts. Be nice to have the best of both worlds, and why not, if it's just a simple switch.

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  5. Modded my board to the new corrected layout and still nodda. I assume the tiny minus signs you can barely see on the electrolytic capacitors designate the negative side. That was the only thing I was thinking could be wrong. I can't find anything, so I'm guessing the layout could still be incorrect.

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  6. As for my electrolytic comment above, you'd think the one 22nf elec. capacitor that has a lead going to the ground track, would have its negative lead attached there? But, according to that tiny negative symbol, it's the positive side going to the ground track. ????

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    1. Hi mate I think your correct regarding the 22uf cap. It looks like a power filtering cap that goes from 18v (+) to GND (-). Comparing a schematic with the layout, I noticed that the 180k and 3.9k resistors from Q3 (base and collector) should go to 18v. I imagine the link should go all the way to 18V so try adding another link to bridge holes 'A9' to 'B9'. Its an easy one if you still have the board made up. This is on my to do list so Good Luck!

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  7. Are you sure these schematics are 19x12 ?

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    1. It says you must make 10 cuts but there are only 8 cuts on each board .

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    2. No, there are 10 cuts. I thought the same thing too, but I eventually came across the two other cuts hiding underneath the 470 ohm resistor. Look a little closer. Also, Stu blue, you're right in questioning the dimensions. It says 19x12, but if you count it up, it's really 19x16.

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  8. Alrighty, after some comparison to the schematic I found, I believe the major issue is that the long jumper wire in column 8 is positioned incorrectly. It should start on row A not B. The resistors at the other end of that jumper (180k, 3.9k) are all suppose to be connected straight to the 18v. Having the jumper start in row A would accomplish that. There could be other problems on top of that correction though, as the negative side of the 22uf cap there is not suppose to be connected straight to 18v, but have the 180k resistor in between it and 18v. IDK though, maybe the way the 180k lays in there is sufficient. I could be wrong, as I'm not that into reading schematics, but something doesn't seem right there, and the above seems logical.

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    1. yep. the link was short 2 rows preventing power getting to Q3, and the 22uF filter cap was reversed. i fixed the layouts and they should be good to go. i also shrunk it by 1 column. if you built the original layout just extend the jumper so it matches the new layout and flip the filter cap and you should be good to go.

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    2. Another one. Assuming the schematic I found is the correct one, the 56k resistor in this build should be a 5.6k resistor.

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    3. it says 5.6k. the decimal is hard to see for some reason.

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  9. Thanks guys for clarifying this , Cant wait to build it , I was well impressed with the Colour Sound Overdrive to think that was only 9v yet the sound was huge. I made the Overdrive over a year or so ago and its still on my board .

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  10. I've made all of the corrections and I'm still not getting any signal coming through. I studied the schematic for long time after that, and thought I'd found other problems with the layout above, but they didn't end up fixing it either. There seemed to be at least 3 places around the transistors that needed to be jumpered, if you follow the schematic. Such as the 150K resistor near the input is connected to both the B & E of that first transistor, but not in the layout above. The other two transistors have a similar disconnection, if I'm correct about interpreting the schematic. I don't see the 1m resistor anywhere in the beginning of the schematic either.
    https://www.element14.com/community/blogs/andybetts/2017/09/01/colorsound-power-boost-18v

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    1. The 1M is a pull down resistor to prevent switch pop and was not on the original, it won't cause any issues. The thing is I see what you're talking about. The problem is that connections in a schematic are usually shown with dots between components if lines goes through each other rather than have a hump showing they're not connected. It could be that wherever lines intersect are connected, but not quite sure with this one. You can try to make those connections and see if that brings it to life.

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  11. Oops, disregard my last entry about the places that need to be jumpered. I found some other schematics that cleared that up for me. 150k is not connected to both the B & E of that transistor and so on. I'm use to seeing a curve in the line if it's not really connected at that point. Either way, I tried all of the corrections out before I made the jumpers and it's still not working. It has to be really close to a working layout, but something is still wrong with mine.

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  12. Yes, you are correct Zack, the dots show the lines that are really connected, and anywhere the line intersects another with out a dot, is not a real connection. I just learned that the hard way, lol.

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    1. Lol. No worries man. There's 2 different ways that schematics can be so it can get confusing. I'm going to see if I can find an actual trace of it to verify some of the connections. It's definitely close, which is infuriating that it's not go to go yet. Lol

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  13. Cool, thanks! There is a trace of it at the link I pasted above, and then there is this picture I found that lays out the positions of the parts. Follow the link below. I reconstructed the layout onto the trace in photoshop, and assuming the image is correct, I could send you the layout file I made.

    http://www.freestompboxes.org/viewtopic.php?f=19&t=27710&p=259435&hilit=powerboost&#p259435

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  14. I did the Early Version with Vol Mod and got it working. I used BC169Cs instead of the BC184, just had to change the order CBE to ECB (Fun!). I only issue I had was I had to change the cable going Vol Lug 1 swap to Lug 3 and Cable Vol 2&3 to Lugs 1&2 so the max Vol was fully clockwise. But this is my first build and I was assuming Lug 1 is LHS. Thanks heaps for posting this Zach

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    1. awesome. i wasn't sure which lugs should be which. i'll make the changes to the layouts and mark it verified.

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    3. Don't see why you think they're fake. Tayda is a reliable seller.

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  16. Is BC 184LC the same as BC 184L?
    Or what about BC 183?

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  18. Hi everybody.

    I'm debbuging my power boost and was wondering what's the role of the cut in B5 ? There's nothing that touch that line apart from the cap and the resistors that are supposed to be connected (in B14,15,16), right ?

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    1. Nothing. It’s left over from when I designed the board originally.

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  19. If you're using BC184L MIND THE PINOUT cause the ones I got were ECB and needed their legs crossed. Those are called gentlemen transistors. And they aren't as polite as their name suggests.

    This thing sounds great. Thanks again!

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  20. Hello guys,

    I'm wondering if one could simply adjust the bias resistors for the use with germanium transistors.

    I'd be sooo grateful if someone could help me with this!
    Maybe someone got the time (:

    Michael

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  22. Greetings guys, I know by now is at least 4 years since anybody posted on this thread. I built the Late version w/ vol and I'm having the same issue of all of the drive bunched up at the end of the pot. Tried a 10KC (anti log) and did not fix it. I an using a charge pump giving me 18.4V and I'm having slightly higher voltages at the transistors than specified, but still in the ballpark.
    Has anybody solve this buched up drive issue?
    I'm using 2N5088 for all 3

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  23. Hi George. According to one of the people who make pcbs/kits for the CSOD you can get the drive sound to kick in earlier with a lower value pot. Instead of the 10 k they were recommending a 5 or lower. I built mine with a 5k. The fuzz side of things kicks in a bit earlier, but still at massive volume. So perhaps try paralleling a 5 or 10 k resistor across your "drive" pot.

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  24. Hey there! First thank you for this great resource. I’ve built lots of fun pedals and learned a lot. I just built this one. I ditched the 10k volume for a 1k, since full gain (volume) @ 0 ohms and way clean @ under 1 k. No more bunching up at the end and very controllable. Also, switched wiring on volume (volume 1&2 on the left, volume 3 on the right). Now it works as expected, with full gain clockwise (0 ohms). I also got rid of the top row, moved the 9V down and moved the cut over, since I have nice 30x15 Stripboard. I used 2n5088s, which match well with the hfe of bc184l and they sound great. Finally, I tried it @ 18volts but I actually think it sounds much better at 9 volts. Thanks again!

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