Yes i meant the two LEDs opposite each other as i think this would look better.
but only one way to find out.. lol. thought the same about connecting two together but didn't realise the 18 count timer..
Project: Madness (a Fan/Electronics modification)
- Thread starter Tealc
- Start date
Yes i meant the two LEDs opposite each other as i think this would look better.
but only one way to find out.. lol. thought the same about connecting two together but didn't realise the 18 count timer..
Right I've tested it and if I short pin 9 to pin 15 (reset) the decade counter resets after pin 9 and starts again. Not sure why it didn't work in multisim testing but it works in real life. Will give it a go anyway just for fun and post results. Shame I didn't try this on breadboard as I could have gone for 16 LEDs which is much easier to wire onto the fan.
Hmm no go at the moment. I've wired up a switch to pins 9 and 4017 pin 15 which seems to reset the circuit but it looks like this is actually not going to work. Pin 9 seems to stop the circuit at 8 and causes pin 9 and pin 5 to flicker. 9 is slightly less bright than 5 but there seems to be an issue there somewhere. No errors in soldering as when run normally no flickering occurs.
Shorting pin 10 to 4017 pin 15 causes the circuit to hang.
Maybe I should try pin 1 of the second 4017....
......nope that halts too and the second output gives strange behaviour too. LEDs that shouldn't be lit flicker when they aren't supposed to.
I think for the time being I'm stuck with 18 LEDs in rotation. I was thinking of getting some 8 circuit dip switches too to have dual modes but maybe the nature if the circuit doesn't allow it.
I think I might need to have a third decade counter separate from the other two which I could enable and disable via a switch. This would be simple enough with a switch on the 555 pin 3 I'd imagine and another bunch of wires on the board.
Shorting pin 10 to 4017 pin 15 causes the circuit to hang.
Maybe I should try pin 1 of the second 4017....
......nope that halts too and the second output gives strange behaviour too. LEDs that shouldn't be lit flicker when they aren't supposed to.
I think for the time being I'm stuck with 18 LEDs in rotation. I was thinking of getting some 8 circuit dip switches too to have dual modes but maybe the nature if the circuit doesn't allow it.
I think I might need to have a third decade counter separate from the other two which I could enable and disable via a switch. This would be simple enough with a switch on the 555 pin 3 I'd imagine and another bunch of wires on the board.
Soldato
you should try doing rgb leds in a sequence next 
you've inspired me to try some led fan mods now
you've inspired me to try some led fan mods now
Hmm. That's a good one. I've got almost 50 common anode RGB LEDs here already.
Sounds like an interesting project. Not quite sure how I could vary the PWM of the individual colour LEDs by using 4017s and 555s automatically but I'm sure it's possible. Maybe trimmers for each colour.
Edit: 3 hours later. Uurgh. This will be a difficult task with discrete components. I could, theoretically string 3 4017s together to trigger 9 Red, then 9 Blue, then 9 Green before the circuit starts again but fading and different colours would be tricky and use hundreds of components. Easier to go with a microcontroller I think.
More thought needed I think.
Sounds like an interesting project. Not quite sure how I could vary the PWM of the individual colour LEDs by using 4017s and 555s automatically but I'm sure it's possible. Maybe trimmers for each colour.
Edit: 3 hours later. Uurgh. This will be a difficult task with discrete components. I could, theoretically string 3 4017s together to trigger 9 Red, then 9 Blue, then 9 Green before the circuit starts again but fading and different colours would be tricky and use hundreds of components. Easier to go with a microcontroller I think.
More thought needed I think.
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In the concept of the HDD light and 100ms time, have you considered running a 555 timer at a 100ms freq, and logic and the HDD line and that 555 timer, this if the HDD line has activity on that 100ms pulse then it does whatever? Just an idea.
This RGB thing has been going through my head for the last few days. I don't know why I can't just leave things alone. 
So I came up with a circuit that would allow me to sequence through the individual colours Red, Green and Blue and also add mixes.
The circuit uses an additional 4017 decade counter IC, on the right, to count Tens while the first 4017, on the left, counts the units and actually drives the LEDs. This will give me up to 9 lighting effect options, more if I cascade. I've only gone up to five LEDs in this example because I couldn't be arsed to do more. :/
I then use a transistor to act as a switch from the outputs on the second 4017. I believe this is a multiplexing technique where a single anode is live when a single cathode goes to ground. Whether the way I have done this is correct or not I'm not sure. It works and that's enough for me.
Integrating dimming effect would be quite complex as I would need at least 6 transistors, if is even possible.
I've been looking at integrated RGB strip controllers such as this which would give me total control over the colour. Indeed I am already waiting for one that I will be using to modify my keyboard backlighting.
I'm not sure how I could integrate this into a sequencing circuit but should be fun trying. I could have course just have 18 LEDs lit by the controller and just have them lit all the time.
Anyway here's a video of the RGB circuit as it stands.
The video, after a time, goes Red, Green, Blue and then on the fourth a sort of Reddy/Orangey/Yellow colour which is created by driving the Red to high current and the Green element to medium current. LEDs don't dim very consistently with resistance but wiring up a variable PWM circuit would just get too complicated.
I'm grabbing some 40106 oscillator ICs which should give me a fading effect rather than this switching effect.
So I came up with a circuit that would allow me to sequence through the individual colours Red, Green and Blue and also add mixes.
The circuit uses an additional 4017 decade counter IC, on the right, to count Tens while the first 4017, on the left, counts the units and actually drives the LEDs. This will give me up to 9 lighting effect options, more if I cascade. I've only gone up to five LEDs in this example because I couldn't be arsed to do more. :/
I then use a transistor to act as a switch from the outputs on the second 4017. I believe this is a multiplexing technique where a single anode is live when a single cathode goes to ground. Whether the way I have done this is correct or not I'm not sure. It works and that's enough for me.
Integrating dimming effect would be quite complex as I would need at least 6 transistors, if is even possible.
I've been looking at integrated RGB strip controllers such as this which would give me total control over the colour. Indeed I am already waiting for one that I will be using to modify my keyboard backlighting.
I'm not sure how I could integrate this into a sequencing circuit but should be fun trying. I could have course just have 18 LEDs lit by the controller and just have them lit all the time.
Anyway here's a video of the RGB circuit as it stands.
The video, after a time, goes Red, Green, Blue and then on the fourth a sort of Reddy/Orangey/Yellow colour which is created by driving the Red to high current and the Green element to medium current. LEDs don't dim very consistently with resistance but wiring up a variable PWM circuit would just get too complicated.
I'm grabbing some 40106 oscillator ICs which should give me a fading effect rather than this switching effect.
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Soldato
niiice, would love some more fans that do that like my top fan on my skelly 
Soldato
yeah that's why I said like
I have a couple of fans that do that already but they have to be plugged into a controller
I have a couple of fans that do that already but they have to be plugged into a controller
