Dimming Analog LED's - No Arduino?

[MuseumEd]

After much discussion and help (see topic "EL"), I've decided to go with analog LED strips for red lighting in a portable planetarium for our museum. We'll need about 10m of LED strip, and it seems like splicing together two reels shouldn't be too hard.

BUT!

We have an existing setup with no Arduino and it would be handy if we could keep using it.

With our current setup we plug a set of quick-to-break-expensive-to-replace LED rope lights into a power supply that we set up inside the planetarium dome. It runs at 110v AC. We use a dimmer switch of the type you'd use on in-home lighting to dim our lights. Could we solder the LED strip to a 110v AC - 12v DC adapter of the type that you'd use for a bread board, plug that into our power supply, and just use the existing dimmer switch?

[adafruit_support_bill]

Regulated Dc power supplies will not like running off a dimmer switch. Since these are analog strips, you might get away with a 12v transformer & rectifier. But most home-type dimmers can generate some nasty spikes that the leds might not tolerate.

An arduino-based PWM dimmer system is fairly simple to implement and not very expensive. If you get stuck, I'm just a Green Line away.

[MuseumEd]

It's good to know you've got our back

I have only the most basic familiarity with Arduino, so I don't know what the actual hardware setup would look like for that system. Would we need to have a little arduino itself plugged in whenever we wanted to use the lights? Would we just have the little arduino hive overmind tell a few chips in some sort of switching setup what to do and then just plug the light strip into that switching system? Thanks for your tech patience.

[adafruit_support_bill]

Would we just have the little arduino hive overmind tell a few chips in some sort of switching setup what to do and then just plug the light strip into that switching system?

Essentially, yes. An Arduino in a box with a power supply and a MOSFET or three to do the switching. The 'user interface' could be as simple as a knob like your current dimmer. Or as fancy as a keypad to let you select preset dimming schemes.

[abqlewis]

I have to agree. The worse time for most regulators is Turn-on, and you would be turning it on and off many times a second. Even if it "worked", it seem like you would be shortening the life of the regulator, and causing reliability issues. A much better idea of course is using the PWM output of a Arduino. It shouldn't be hard to find, or just create, a simple sketch, but you will need some switching circuitry (transistor-ish), because the Arduino can't handle the LED string's high current 12V. But you could get help here from Adafruit.
If you are really adverse to using Arduino, I have seen DIY LED dimmers using 555 chips. Just Google 555 LED dimmer. Bad news is this would be without Adafruit support.
Lastly there are manual dimmers made for LED strings. Again, just Google PWM LED Dimmer. Amazon has one for $10, and they even show something of a hack on the product page.

[MuseumEd]

This is all very helpful. One of the folks in our department is Arduino saavy, and I've got some experience with transistors and switching. We might collaborate on a DIY piece, or the higher-ups may tell us to just save time and buy the off-the-shelf dimmer. Either way, this has given us much better information for choosing out systems.

thanks from the MOS!