Power supply make or buy

[GibsonGM]

The old conundrum - safety vs. learning, growing, understanding and gaining competence.   Working w/mains-wired projects is certainly no more (or is it less?) dangerous than learning to operate a chain saw.   I think perhaps the deciding factor might be if there is someone who ACTUALLY is knowledgeable - not a 'poser' - who could tutor you as you step into the land of transformers, fuses, safety grounds and the like.  Uncovering/understanding the hidden dangers that aren't intuitive BEFORE they get you is critically important (just like chain saw kickback dangers).

I could do home wiring before I could safely build mains-powered stuff. This probably helped a lot - the repetition of hot, neutral, ground and what they do. Safety routines that become 2nd nature ("lock out/tag out", pre-powering safety review).  It's not something I'd say 'don't ever learn!' - but I'd really want the new person to have the proper guidance because yes, there are a few ways one can kill themselves pretty easily if they mess things up!   There are also methods to test what you've built without putting yourself in jeopardy before you 'use' the device.

Nothing can replace training, IMO - an adult ed course, or even your father in law IF he's competent    Don't be afraid, but be very respectful of things that can potentially end you.  And weigh how much the end goal is worth vs. what you're willing to learn and apply before engaging in the potentially dangerous activity...that's why my earlier reply of 'just buy the thing'.   Something moved and used hard will have been failure-tested by the company that made it, where we really can't do that stuff, so we can't know how it will eventually 'die' on us (and maybe present a shock hazard).

[amptramp]

If you are making something to sell, you need to have UL or CSA compliance in North America or VDE in Europe.  If you are building a single item to sell, sell the wall wart with it that has these certifications or you will be liable for any damage caused by faults.

Even if you are updating an amplifier from a 2-wire plug to a 3-wire plug, there are certain requirements that are not obvious: if the ground lead is connected to the chassis via a terminal lug, this hardware cannot be used for anything else.  I have seen amp repairmen use the mounting screw for a transformer as the place to put a ground lug and that does not meet UL/CSA requirements.  Similarly, you can only use certain types of wire on the primary side in order to comply with the code.

If you are building something for yourself, there are ne restrictions, but you are still liable for damage if things go wrong.  There have been hundreds of magazines of DIY projects for stuff you plug into the AC line and companies making kits where the capabilities of the builder are in doubt but as long as the unit has the capability of meeting standards, you are pretty much OK.

[Phend]

Here are two of my electrical projects from many years ago.
Dismantled for the most part.
UL (Uderly Loony) builds not approved. DANGEROUS PROJECTS (I am lucky)
First was a modified power supply (Heathkit TV build unit) a friend gave me.
I added a powerstat, rectifier (not shown), capacitors, high watt resistors, pots etc. to the inside of the unit.
Project: Anodize Titanium using TSP and an artist brush wired to DC.
The second project was a ruby laser. I polished the ruby rod and added flash tubes etc.
So let me think.   General Guitar Gadgets has a few circuits as well as the net.
Or those nice (not cheapo units) PSU's for sale.
Thanks for the input.

dangerous than learning to operate a chain saw

Ha, just bough an electric one (battery) that is.

[MrStab]

It can be helpful to actually see a lot of commercial, certified mains equipment, and how it's done.

...without them being plugged in. With at least a decade since last power cycle, to ensure sufficient cap discharge. And various other disclaimers to absolve me of responsibility.

[GibsonGM]

Ha, just bough an electric one (battery) that is.

I have a Stihl MS290 that I use to cut a 10-cord load of trees into ~8 cords of stacked wood every year. That's what I heat with.  B@stard will take your leg right off in 1 second if you're not careful, but it's a great tool I've had for a decade with NO problems.  Go thru at 20" log in about 10 seconds.

Also used to clear the occasional tree from across the road, since this is rural Maine!    We keep one in the truck.

I'd like a cordless for going up in trees to remove dead limbs - seems like it might be lighter.  Or for cutting fence posts (4x4, 6x6), things like that.

Will it quarter a moose?

[Phend]

Yes, DeWalt XR 20v 12 inch, you could climb trees with it, I've cut 12 inch butternut like going thru butter. 250$ at Ace Hardware.
With proper attire (red flannel) yes. Always wear your safety glasses.
Up next, what PSU ?

[Phend]

Considering making this 8 holer.
Hammond 1590DEBK (7.88 x 4.73 x 2.53) black
Have terminal strips, led, and switch from a past projects.
Buy DC Button Jacks.
Power Unit : Truetone 1 Spot 9v 1700mA

[GibsonGM]

Most important safety equip. in my world - chaps!  The mylar can stop a chain from taking your leg off. Steel toe boots, too.

That distribution box is pretty nifty

[Phend]

Just completed a distribution box for a Truetone 1Spot.
Thanks RG for sending me there.
Added a switch and a Led with resistor.
Tested voltages and had to do some head scratching.
1 Spot plugged in, switch on, led lights and getting 9.52 volts at each outlet and across the strips.
OK simple enough circuit this one.
1 Spot plugged in, switch off, led off, getting about Negative 2 volts.
Disconnect led and get Negative 0.3 volts.
Hum, tried a diode, no effect.
So thinking maybe a 100k bleed resistor (if that is what it is).
Bingo
On : 9.52 volts
Off : 0.000 volts instantly.
Now time to build the third (of seven) accessories.

[PRR]

Just completed a distribution box....

Nice work. But uh....

Why not a couple 8-way WAGOs?
https://www.amazon.com/Connector-PCT-218-Classified-Conductor-Terminal/dp/B08ZSFXWN7/

[DIY Bass]

This power supply kit/pcb looks well done to me.  240v though.  You would need a different set of transformers if you lived somewhere that doesn't provide 240v

https://guitar-electronics.eu/en_US/c/Power-Supply/102

[Phend]

Why not a couple 8-way WAGOs?

I had the terminal strips from another project.
Will remember the cable management gizmo, PRR.
The 1 Spot has a daisy chain accessory option.
Plus they sell "boxed up" PSUs , a higher level.
But thought I wold build my own daisy chain in a box.
Just another DIY project. Needs a label.
PS The four screws washers and nuts were pricey, like all fasteners.
  I didn't go broke buying them, just saying.

[stallik]

Nice solid build. Probably last much longer than mine but I doubt it would fit in the tiny space under my pedalboard

[PRR]

  I didn't go broke buying them, just saying.

No. But a lot of stripping and screwing. And busing and crimping. Appropriate if you get paid by the hour. It occurred to me that non-wirepersons might not know the newer (~~30 years) inventions in the field.

"WAGO" is a brandname for similar push-in multi-connectors. The piano-lever connectors are something else, but I was getting Asian copies. Image search, 8-way connector, may be a start.

[antonis]

IMHO, use of WAGO or any other similar connector device is overkill..

P.S.
I DO use a lot of those connectors in power supply builds of 5 Amps (or more) but for pedal supplies... 

[Phend]

Not thinking about mfg these in large quantities, too old for that, like I am done.
But I did have Fun building it and I needed one.
Thanks for all the input on all post in this topic. !!

[Rob Strand]

Since you went for a regulated power supply you might want to add a dummy load of 220 ohm (1W) inside the unit.   While perhaps not require for use with the One-spot, in general some power supplies are very noisy with light loads.  There's quite a few posts in recent years on this forum about it.  The dummy load saves the day in many of those cases.

[bluebunny]

What a good idea, Kevin.  This would use up some of those metal-bodied DC jacks I bought by mistake. 

[stallik]

^ you must have read my mind - that's precisely my reason for using them and I've still got enough  for another 2 boxes should I need them

[Ben N]

Just completed a distribution box for a Truetone 1Spot.

The 1Spot is great, and I use one. But if you had 12vdc coming in, you could have separate regulation + filtering on each 9v output, in addition to 12v where needed.