Ay! My intuition paid off for once
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I’ll be building on my live stream tomorrow - that is Wednesday 8/12 at 12noon EST if anyone wants to come and hang out
https://www.twitch.tv/zorch1138
I’ll be trying to figure out what I did wrong on my FC Power supply.
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No power to the -12 side for some reason.
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Check for diode polarity errors. If the +12V is coming through loud and clear the diode on the negative rail occurs to me as your most likely problem.
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the regulator heat sinks not touching ? can’t tell from picture but that could cause problem and maybe the diode under the blue 100 uf cap could be sorted ? the solder joint on the resistor by green led looks a little sketchy .
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Those joints are all fine.
Is sharing a common heatsink a bad thing?
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YES
They are connected to two different voltages. Bad if they touch (or are one and the same).
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By the way, if you’re looking for (or offering) help with a particular circuit, it’s better to post in a topic (new or existing) dedicated to that circuit rather than tossing them all into a topic with your name on it. Reason being that later posters looking for help can find it easier that way.
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This is fair. Normally I would but this time the pleas for help just kinda happened!
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Currently streaming right now! I have my heatsink off and cut. Now trying to test the regulators to see if they are damaged.
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Power supply 1 of 2, now working! Sadly my oscillator still is not. Moving on to the other power supply for now.
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glad to hear you got it working . it is kinda odd that it doesn’t say anything in the micro bus build document about the heat sinks not touching . I only knew about it from building some other brand power supply and it did say to keep them separate or bad things would happen .
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Having two separate heat sinks did indeed fix the problem on power supply #1. Luckily none of the other components were damaged in the incident. Power Supply #2 suffered from a miss soldered lug on the barrel jacks and actually burnt out my wall wart. Thankfully that was an easier fix.
That brings us back to the oscillator now that things are good on the power front. I got my first magic smoke! 4 of my TL02 's were damaged during my previous build attempts. On the good side, I was able to weed them out easily as they all got super hot the moment I plugged them in.
I have a total of five CEM3340 chips. The first one was a knockoff that I got through ebay and has most likely suffered the most of all of them. The other four I got in a batch from https://synthcube.com/
Currently - No matter what chip I use I have no triangle out. The knockoff produces a sawtooth that sounds correct, and one of the CEM chips seems to produce a very low frequency oscillation while none of the others seem to do anything at all. Any ideas why this would be? From looking at the annotated schematic, everything seems to be giving the correct voltages.
I feel like I am making some progress. It sure has been rough going! My next step is to give the oscillator build from scratch another stab. I might do it on stream next week.
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Weyyy! your IC popping cherry popped. My first was a TL072 also… but it was the Envelope Generator v2 (3 popped)
@Caustic Thats amazing! i didnt understand at first… that first line tho XD
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Going to be streaming again today - working on more modules. I’m still undecided on what one to do next. Any suggestions? I could work on (and possibly finish) these:
LFO
Filter
ASDR
Oscillator #2
I can also start on:
VCA (still waiting on the tube & socket)
Envelope generator
Sequencer
Fart Box
EDIT: Currently finishing up the LFO - about to test
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One of these days, I’ll get a project to work right on the first try. But today is not that day!
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All that matters is that it works on your last try.
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no thats great that they don’t always work first try , that way I know its not just me 
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