It's new, but also very retro

It's nice that they've included a PTC overcurrent protection device.

Big Clive

I bought 4 at about $1.50 US each, delivered from China. https://www.ebay.com/itm/264844260167

Philip Childs

I was wondering the same thing. I seem to remember something about the 7555 (the CMOS variant of the 555) being able to go rail-to-rail, but I don't know if that meant they could go full on or full off in a PWM configuration. It kinda makes me want to whip one up on a breadboard and see.

Circuitmike

That's what it was, black and chared kerboom, the fuse was the only thing that survived !

U can use just 3 regular led dimmers aswell and mark them r g b it looks kinda like thath circuit

henrik ostrov

I can guess it's like the inline dimmer I took apart a while ago. Very minimalist and cramped. I managed to kill it with the wrong type of load.

Big Clive

I don't know if the 555 can PWM fully to on and off.

Big Clive

Nice video, Clive. And a neat design and unit. I applaud the single sided layout. Are the pots log law? I'm guessing not, but that's one thing that's easier in firmware - just saying. As these are opamps used as comparators (nothing wrong with that per se), I would have liked to see some hysteresis to prevent chattering at the switching point. That might have allowed SOT23 FETs instead of SOT223. What saith the Flir?

Mike Page

I'm not sure if I'm disappointed or impressed that they not just used three 555 timers in PWM configuration.

MrTridac

I suggest a look at the cheap and impressively explosive dimmers that come with the Ebay Salt Lamps ! No strain relief, neutral runs with insulation in contact with the solder side of the pcb, live runs over the tab of the thyristor ! Extra explosive due to the 13A Chinese sand free fuse used on a 15 / 25w bulb ! Basic pot diac thyristor ciruit with minimal insulation :( Keywords, Salt Lamp Dimmer

Less than a tenner on eBay, might get one because I've fancied a bit of RGB tape and this is just so simple.

Matt Tester

Keywords are RGB dimmer knob.

Big Clive

Many thanks Travis. I can get it on ebay UK https://www.ebay.co.uk/itm/353439308142

Nuts 'n' Proud

Somebody shared this up above from a US shipper (presumably search terms win be helpful even if you want shipping from elsewhere.) Only $12! https://www.ebay.com/itm/RGB-Knob-Dimmer-Smart-LED-Light-Brightness-Adjustment-3-Channel-Controller-/353439308142?_trksid=p2349624.m46890.l49286

Travis Terrell

It could be a micro controller with a fixed ROM. No really Clive was naughty.

Nuts 'n' Proud

Clive, I love that bit of kit. If something dies I can get the bits. No custom micro controller. I would love to get one of those controllers. Could you can suggest a search on Ebay?

Nuts 'n' Proud

The 555's not a microcontroller, Clive. Geez! ; )

Travis Terrell

Just missing the ram and a bus!

Travis Terrell

this housing breathes early 1980ies vibes, just missing some venere decal...

Andreas Dorfer

Very interesting.

mj

Pedantry in 2021? Who has time for that? Fabulous video as always Clive!

Crobisaur

Pedants? In YouTube comments? Shirley you jest

Chipmunk

£15 on wish...Christ!...that's expensive for wish...

Just found the exact same one on ?? Agouk.com £6....22 to 86 days shipping though...meh, nice surprise if and when they turn up

Clarification: ships from China, i just mean its on US ebay!

Jeremy Impson

I found a US ebay source here: https://www.ebay.com/itm/RGB-Knob-Dimmer-Smart-LED-Light-Brightness-Adjustment-3-Channel-Controller/353439308142

Jeremy Impson

Any idea where I could get one of those modules either kit or prebuilt?

(also, I wrote the above before finishing the video, so maybe you cover this later :D)

I also found it a bit odd at first that they're using a voltage regulator for a circuit that's otherwise independent from the supply voltage, but seems max supply for the NE555 is 16 volts or so. Also simplifies driving the MOSFETs, I guess.

Nit: the 555 thresholds are 1/3 and 2/3 of the supply voltage, so the triangle wave will swing between 1.7 and 3.3 volts, not near the rails (and be slightly curved, since the charge current varies over time). Didn't you have one of those small oscilloscopes? You should use that one more often :-) (the internal voltage divider uses three 5k resistors, btw, which is why pretty much every article about this chip claims it's named after these resistors, but the designer Camenzind says it's just a coincidence.)

Wow that is old school and yeah modifiable! Nice!

Michael Thompson

Ha! I was yelling at the screen about the missed solder joint. Glad you heard me :-)

Bill Kerr

yup. I usually use something like this to pick values when i need specific colors from rgb leds: https://htmlcolorcodes.com/color-picker/

Can you bring up a true yellow by adjusting green and red?

Jonathan Hughes

https://en.wikipedia.org/wiki/MPC5xx -- The MPC5xx family of processors such as the MPC555 and MPC565 are 32-bit PowerPC embedded microprocessors that operate between 40 and 66 MHz and are frequently used in automotive applications including engine and transmission controllers.

adrian