I have a few questions regarding powering your projects/experiments.
I am working with the well-known frequency central DIY power supply and I apparently busted the 5V and I would like to fix it. There is no visual clue as to what is wrong, so I suspect that I broke the voltage regulator. It might be caused by accidentally shorting 5V to 12V or to ground because of small bits of wire that ended up under the PCB. So would a new 5V regulator fix that, you think?
So, like others, I accidentally short things every now and then. This can be caused by breadboarding accidents or by connecting an new untested module that has a soldering mistake near the power-lines. I know that bench power supplies are rather helpful there because they apparently shut down and light some over-current protection LED. Without this, it takes more debugging time and in the process, you might actually damage your powersupply, which is apparently possible as I have learned.
Does anybody know of any good solutions for eurorack? I would love to have a bench PSU that could spit out all required eurorack voltages at the same time, but that would not be cheap I think. Perhaps there might be a kind of protection circuit I can drop on the individual +12/-12/5 V lines. It might be a fun project to create such a protection circuit that would also show the currents being drawn on 3 LCD displays.
Does any such solution exist? Looking forward to read your replies
I’ve mentioned it before I think, but I use industrial DC-DC converters for initial testing of individual modules, powered from a USB brick. The SIP-8 versions are ludicrously tiny (21.8 x 9.2 x 11.1mm, yes that’s mm), handles shorts without flinching, and while not supercheap they’re not that expensive. You can get 6 W versions that provide ±12 V 250 mA, and 1W versions for 5 V at 200 mA (or if you feel more adventurous feed in the USB 5 V directly, via a polyfuse).
That’s pretty likely, and a 78L05 costs nothing so replacing that is a good place to start (9 cents from Tayda, a bit more from the big distributors but still not a lot).
I’ve mentioned it before I think, but I use industrial DC-DC converters for initial testing of individual modules, powered from a USB brick. The SIP-8 versions are ludicrously tiny
I did some googling but I couldn’t find a product that looked like a USB-driven power supply. Can you tell me where you can buy the product you are suggesting? It does sound like a great solution. Are there any risks to connecting it to a modular that is powered from a different power supply?
That’s pretty likely, and a 78L05 costs nothing so replacing that is a good place to start (9 cents from Tayda, a bit more from the big distributors but still not a lot).
I managed to pry the old one off and put in a new one and it works again!
Removing the old one and all the solder took me about an hour. I really need to figure out how I can get faster at this because it is very frustrating. I suspect my iron might not be hot enough (even though it is an old Weller iron so it should be good). Also removing tiny drops of solder that block the holes in the board is very annoying. In the end I could poke out the solder by moving a solid wire through the hole while heating it.
I built the one in the picture, but the tiny black box on the red PCB is a standard 5 V to ±12 V DC-DC converter (the one in that picture is a Recom RS6-0512D that you can get from e.g. Mouser for a bit over $10). Similar converters are made by several manufacturers (this post has some names). You can build something similar on a breadboard.
I did use wick + flux but I guess I might be doing it wrong. I unroll a bit of wick from the roll and hold the roll while desoldering, but I later figured that this might not work well since it will conduct heat so it will take much longer for the actual joint to heat up. I might need to get myself some non-heat-conducting tweezers to hold a tiny bit of wick against the joint instead. Is that how you should do it?
@Dud Thanks! I do check the headers for shorts but I should perhaps be more thorough when breadboarding or leaving my circuitboards exposed. When you are experimenting, you might not always stop and do a full check. So I put some ducktape under my PSU board as well as under the power bus board.
I really need to figure out how I can get faster at this because it is very frustrating. I suspect my iron might not be hot enough (even though it is an old Weller iron so it should be good). Also removing tiny drops of solder that block the holes in the board is very annoying. In the end I could poke out the solder by moving a solid wire through the hole while heating it.
