My build progress

Headers are good on the ADSR but fried the 10R resistors.

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Question one is, with power off, do you have shorts on the bus bar between Ā±12V or between either and ground?

Then question two is, with power on (and no modules plugged into the bus bar!), do you have Ā±12V and ground on the correct connector pins on the bus bar?

Maybe youā€™ve checked those already ā€” I certainly wouldnā€™t power the bus bar without checking for shorts first, and wouldnā€™t plug in a module without checking voltages.

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^ this. very much this ^^^^

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Yeah got overly excited, should have triple checked everything before I plugged things in.

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Iā€™m diving into the SMD world next week. Not a good sign to hear that youā€™ve failed miserably knowing that you have more experience with soldering than I do. Iā€™m crossing my fingers that I do not fail. That being said I have heard that good tweezers are essential and some sort of magnifier whether itā€™s a loupe or headset like @analogoutput mentioned. Every video Iā€™ve watched on it people have said the key to success is ā€œflux, flux, flux.ā€

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how many times have you posted this video now on this forum? :wink:

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Is the PSU itself even giving out the right voltages? the markings donā€™t say what itā€™s supposed to put out.

Rob

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Looks like a Meanwell RT-65, hopefully an RT-65B (the last letter is important).

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I donā€™t want to discourage anyone! I think it was basically that I thought ā€žhow hard can it be?ā€œ and underestimated the challenge :wink: I used my 15ā‚¬ 20 year old soldering iron (probably 15 Mark back then) and no flux at allā€¦ a Setup I can not recommend.
I am considering buying a new iron, but for this chip I asked a friend and he will do it for me, because I donā€™t want to ruin a 15ā‚¬ chip with my practice, even with better equipment :slight_smile:

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Not enough? ā€¦

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This is what I did for my first SMD:


Then I built one of these, low part count, one small IC. Still, I needed outside help to find and fix up my mistakes.

Then I built three of these. My first PCB layout, but also good for SMD practice.
IMG_6083x
First one with the top tweezers (sucked), second two with the bottom (way better).

Last and most recently I built this:

Also low part count, two small ICs. Didnā€™t work at first but I found and fixed my soldering problem. So Iā€™m getting there.

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Itā€™s the RT65B bought it as a kit with 2 bus boards. I have zero experience with electronics other than simple builds, non modular. Problem has to be with the power and Iā€™m sure itā€™s something simple and Iā€™m looking right at it. Not very confident in my trouble shooting, should have just bought a finished power supply from TipTop or something instead of a kit. Changed out the parts I smoked last night and was, after a few more beers, pissed. Soooo checked the headers, flowed solder, and decided at some point to hook up the other adsr and smoke at the same 10R resistors. This confirmed 3 thingsā€¦1. I am a dumb ass for doing that but was confident in my build. Not being shy about fixing things since that is my profession, my drunken logic was if it smokes at the same place on a different adsr then it has to be the power right?..2. I have confirmed the definition of insanityā€¦3. I have no clue how to truly troubleshoot electrics. That said I donā€™t quit, please see confirmation #2. I will sort this, I do not have the electrical pralis but I never give up, there is that pinhole of light.

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The RT 65B should be fine (and iiuc fairly robust against shorts etc, even if I havenā€™t tested that in practice :slight_smile: ), and the wiring in your photo looks nice and clean, so I donā€™t think the problem is on that side.

Your next step now is to unplug your module, optionally remove the ICs, and use your multimeter to make sure you have connectivity from the two 12 V rails to where you should have 12 V power, and no connectivity between the 12 V rails and ground (if you keep destroying the 10 ohm resistors, odds are the latter is your problem) (if you donā€™t have a multimeter, you need to fix that first).

Feel free to open a new topic and post some pictures of your boards if you want people help you look for potential problems.

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Itā€™s entirely possible you will find SMDā€™s easier depending on how you do it! failure isnt a problem anyway just remember that.

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Thank you fredrik I really appreciate the help from all of you guys.

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Actually I completed this Barton FM Drum several days ago, but didnā€™t get around to checking it out until just now.


It makes noises and all the controls do somethingā€¦ whether theyā€™re the intended noises and somethings, who knows? Behavior seems kind of unexpected in some ways, but maybe thatā€™s not a bad thing. Most of the unexpectedness occurs at high pot settings, which maybe is expected unexpectedness.

For sure the trigger input isā€¦ idiosyncratic. The instructions say

A trigger or gate signal should be input here. The .01uf capacitor and
100K resistor to ground form a pulse shortener, making the pulse length of the input signal
irrelevant.

but a gate from my KeyStep causes it to trigger twice, once at the start of the gate and once at the stop. But if I run that same gate through a buffered multiple it behaves okay.

Incidentally that uses the 84th HP of my 84HP case.

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next project a new case ?

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One of the next. But needs a trip to buy wood and Iā€™m not enthusiastic about doing that right now.

Mail order parts are another story.

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Hi! Iā€™m new to discourse and this group. Is this a general thread for build progress? It looks like you all are making amazing stuff. Iā€™ve been cooped up and put together some basic synth components from junk I have laying around and can share it if this is the right thread. Do you post sound files too? I would love to hear some of these pieces.

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Yeah this has turned into the ā€œpost your stuffā€ thread. Feel free to make a new one for any projects too though. Itā€™s pretty loosey goosey here.

laughteifling

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