I got some led lights on some Garland I just bought and the power supply on it has 8 modes on it ( chasing , Blinking etc.) and I would just like to have them be steady on. There is a selection for steady on but it doesn't remember that selection when powered off so you would have to access the power supply each time you turned them on, which isn't possible for where I want to put them.
I took a power supply from another strand I had that is the same voltage and Amperage but it only turns lights on or off. When I plug the LED strand into this power supply every other light is off.
Having never done anything with LED lights before I'm at a loss for why that happens and if someone has a quick and dirty solution I'm all ears, just trying to not go get another strand when I already have this one.
Thanks in advance
There are lots of different lights like this - if they are the ones I am thinking of. They have a special power supply that is specific to them - and a few models of them. As I recall, the first generation required you to press the "on" button to make them go on at all, then subsequent presses woudl toggle throught the modes. But if you unplugged them, you needed to physically push the "on" button on them to get them to go on. This meant they woudln't work work things like timers or any kind of home automation.
So they made a newer version, that would remember the last setting. So any time you plugged them back in, they would remember the last setting. But some of these just had a simple "on" and "off" switch/setting.
So - long story short - even though they look the same, these might be very different power supplies that operate totally differently.
If one "power supply" is a controller, and the other isn't, you would have to do some cutting connectors anyway. Because, you have already learned that what you have won't turn them all on. That is why I suggested an alternative power source.
We're already off course because of lack of details. Please post links and images that will illuminate your hardware for us.
Without more specifics, this sounds to me like you have a string of lights with addressable LED's (think WS2812's). If that's the case, you need a controller; not a power supply.
No, @anon57585045 is correct, the LEDs in the string are ordinary/dumb single colour LEDs, probably all connected in parallel, but they alternate direction between the two wires. That's why only half of them light when connected to a DC power supply. If @timinelmira finds a way to reverse the voltage from the power supply, the other half of the LEDs will light.
An AC power supply of the same voltage and current would probably be the easiest way to make all LEDs light together.
Another option could be to use an h-bridge controlled by an Arduino, but these parts might cost more than the LEDs.
Look at these. Look at the power supply. This is one of two VERY similar ones I've gotten, with the above differences. The LEDs connect to the supply with a screw connector and there are only TWO conductors. (I can elaborate on how this works) but they are NOT individually addressable, and the control is done by sending current in both directions through these leads, each direction allows it to independently control (and animate) brightness of HALF the bulbs in the strand.
With "Christmas Lights" the lights and controller are usually packaged together and you usually don't know what you have so they are hard to modify/hack.
There are various kinds of LED strips and WS2812 "Neopixels" (or similar) are individually addressable and super-easy to wire-up.
I did, but most still goes right over my head. LOL
The main thing I've learned from playing with an Arduino is that Electrical Engineers earn their money, so many small details that can create such havoc if you're not paying attention.
That is true, but it is also a "craft" that you can learn, and make a lot of things work by obeying the general rules and copying what other people do. That was me, for the first few years...
I was in electronics for 20 years before I went to school for it.
P.S. A lot of it is learning to measure. Get yourself a DMM and scope if you can.
