TheOcularMan

Well originally I was going to tell you to connect it to an 'Arduino' type board. However upon further investigation, I think the motion is controlled by 'wire', like a Muppet. So... I'm at a loss for a simple solution.
 
To confirm, dose it take batteries?

Oops, sorry have been busy with getting back to work and forgot to check back.
 
I believe it does take batteries but I will confirm when I get home.
 
EDIT: Actually, come to think of it, I see what you mean. There is an on/off switch on the toy, and now that I actually put my brain to use I'm remembering that the switch only turns the sound on and off. The toy is operated mechanically, which complicates things.
 
Oh well. Thanks for the reply! Lol.

Hi guys, I'm looking for a new mechanical keyboard that I can do my school work with and also game with. Right now I'm looking at the Logitech G Pro Keyboard, as well as the Ducky One 2 TKL. What do you guys suggest, and do you have any other options that you like and why? (I don't really care about the difference in switches as long as it is comfortable to type on (has to be mechanical and RGB of course) and is TKL and under the price of around $100) Thank you for your help!

If you are going for the Logitech G Pro keyboard (Which is unlikely to be less than $100 at least where I'm at) you should get the newer version the Logitech G Pro X since its basically the same keyboard but with swappable switches. The Romer-G switches is quite fragile if you game hard with it, and I had my G413 fail on me after just 9 months of usage.
 
Edit : I'm currently using the Tecware phantom 87. It's quite great but I would recommend you to actually change all the switches to gaterons or anything thats not outemu since they're kinda crap. https://www.amazon.com/Tecware-Phantom-Mechanical-Keyboard-Outemu/dp/B079HTZQYV

These guys are awesome.

"ultra portable desktop with integrated keyboard"

"ultra portable desktop with integrated keyboard"

I guess yes, I might need a better name though because laptop might not be appropriate.

Better Light on these pictures.

A Company has revealed their light bending film that is almost like an invisibility cloak in fantasy after seven years, and is hoping to pitch it to the military.
 
Source:http://www.hyperstealth.com/Quantum-Stealth/
https://www.sciencetimes.com/articles/24085/20191017/perfect-camouflage-invisibility-screen-completely-hides-soldiers-vehicles.htm
Thoughts: Can't wait for Linus' review on this masterpiece.

@TheOcularMan @Unimportant
Alright thanks for the answers, I'm not sure if the built in pwm function still works if you start messing with the timers so I changed my code and used timer2 for the leds. I was already using leds with the BJT but not with pwm. So later this week I will swap some pins and check if the current leds can be controlled with pwm on timer2.
 
Here is the code:
Edit: Okay I couldnt wait and rewired some stuff: it works ?
 
https://i.imgur.com/VO3I3eM.mp4

I would stay below 1Mhz.
Your right, there isn't, I have found that anything over 100Hz is good (browse my status updates, I posted something about it). Some led driver chips clock in at 10kHz.
 
If you want my honest opinion, I would just use the built in pwm 'function' that arduino offers.
analogWrite(pin, duty_cycle); //500Hz, duty 0-255 = 0%-100% It makes things simple and portable, 8bit resolution. Driving it faster than 500Hz doesn't really 'do' anything (somebody can chime in if I'm wrong).
 
From what I was able to find, it looks like each timer(0-2) can be set with its own prescale value, and each timer has two 'channels' that can be assigned a specific 'duty' value. I think one of the timers is used by the uart though.
 
Resources
 

but why? so many security vunerabilities. also, use stuff like WINE to get windows stuff working on linux

WinFLP, lol "off a legitimate install disk".

Windows XP off a legitimate install disk.

Hi all,
So I'm planning on making my own led strips and controlling them with the PWM functionality of my existing arduino fan controller. Due to the timer limitions and already existing code and hooked up pins it would be easiest for me to use timer2 for controlling the duty cycle of the leds. I would only have to move the pin of the transistor base to either pin 3 or 11. This does however require at least 4kHz, I cannot really go any lower on a prescale factor of 8 (already sacrificing 0.3% duty cycle resolution up to 2.5% for my fans that way).
 
My question: is 4kHz a realistic frequency for driving a 12V ledstrip with a bipolar junction transistor or is too high?
I know when I would switch to prescale 8 (currently not using a prescaler) I could switch the fans to timer2 and use the 16bit timer1 and go as low as I want but that would mean I have to rewire my entire layout so I'm just scoping out my options for now.
Thnx!
 
Edit: I assumed the prescaler is fixed accross all timers, now I'm not that sure anymore. Can I use different prescalers with each timer?

The BJT model is NJT4031NT1G, the ebay listing says the 'transition frequency' is 215MHz, is that it?
This spec sheets says nothing about switching characteristics... https://www.onsemi.com/pub/Collateral/NJT4031N-D.PDF
Its an arduino uno, atmega 328p. And yes I'm using the IDE.
If I can use separate prescalers I dont have an issue at all, I can use no prescaler and 640 steps for 25kHz and a 64 prescaler and 255 steps for the leds for ~490Hz.
Still interested to know what good pwm frequencies are for LED circuits, there doesn't seems to be a lot of quantative info about it...

Hi everyone,
 
Halloween is about 6 weeks away and I've been working on a Halloween project for work, utilizing a rpi3, an adafruit dc motor HAT, stepper motors, a ping pong ball, a webcam and magnets! What I am contemplating is an 'eyeball' in a glass mason jar that turns to follow those who dare pass by.  I'm only about 25% complete (I believe the software side is all functional at this point...it's just a matter of waiting on parts and assembly) Here's what I have so far...
 
Initially testing tracking software with a pi zero...quickly realized it's just too slow to be able to effectively 'follow' an object. I was planning on using r/c car servos I had laying around the house, but running servos directly off of the I/O pins (as evidenced in the video) results in very imprecise and jerky movement. Ordered a pi3, an Adafruit DC motor HAT and 2 stepper motors...

20190918_133635_2739454214056.mp4

Your calculation for findB is wrong... it should be return y - (m*x) it's not division it's subtraction but other than that this helped me because I was having a hard time with the intersection part which you did very well. I translated it back to a program in actionscript 2.0 that runs once and prints then exits. Here it is...
var test = true; onEnterFrame = function () { if (test) { var PI = 3.14195; //calculates pi, 3.14159 //data set 1 var x1 = 10; var y1 = 23; var x2 = 65; var y2 = -17; //data set 2 var x3 = 49; var y3 = 25; var x4 = 7; var y4 = -12; var m1 = findM(x1, y1, x2, y2); var m2 = findM(x3, y3, x4, y4); var a = findB(y1, x1, m1); var b = findB(y3, x3, m2); /* view work so far */ trace("EQUATION 1: "); printLineEqu(m1, a); trace("EQUATION 2: "); printLineEqu(m2, b); /* done */ //parallel line check if ((m2-m1) == 0) { trace("both lines are parallel."); return 0; //exit if out of range } //calculate theta var theta = findTheta(m1, m2); if ((theta<0) || (theta>(PI/2))) { trace("theta: "+theta); trace("angle out of range."); return 0; //exit if out of range } //find intersections, if all is well var Xintersection = findXintersection(a, b, m1, m2); trace("X intersection: "+Xintersection); var Yintersection = findYintersection(a, b, m1, m2); trace("Y intersection: "+Yintersection); test = false; } }; //used for plotting on ti-89 as check, plug and chug function printLineEqu(_m:Number, _b:Number) { if (_b<0) { trace("Y = "+_m+"*x"+_b); } else { trace("Y = "+_m+"*x+"+_b); } } //find theta function findTheta(_m1:Number, _m2:Number):Number { _theta = (_m1-_m2)/(1+(_m1*_m2)); _theta = Math.abs(_theta); //absolute value _theta = Math.atan(_theta); //inverse tan return _theta; } //find the y intersection function findYintersection(_a:Number, _b:Number, _m1:Number, _m2:Number):Number { return ((_a*_m2)-(_b*_m1))/(_m2-_m1); } //Fine the x intersection function findXintersection(_a:Number, _b:Number, _m1:Number, _m2:Number):Number { return (_a-_b)/(_m2-_m1); } //find slope function findM(_x1:Number, _y1:Number, _x2:Number, _y2:Number):Number { return (_y2-_y1)/(_x2-_x1); } //find b function findB(_yB:Number, _xB:Number, _mB:Number):Number { return (_yB-(_mB*_xB)); } //find X intercept function findXintercept(_m:Number, _b:Number):Number { return ((0-_b)/_m); } //find Y intercept function findYintercept(_m:Number, _b:Number):Number { return ((_m*0)+_b); } Thanks alot!

I know nothing about magnetic core memory. In fact, you will be really hard pressed to find anybody who dose. Here's the good news, I found some information you may be interested in.
core memory shield for arduino
shield documentation
creators website
his contact information
 
another core mem project (with resources)
Edit: more info
contact info
more contact information
 
What I would do, is just buy the kit. If you enjoy pain and suffering, shoot those folks an email and make friends. The hardest part of this endeavor is going to be tracking down useful information about the topic. Most of the brilliant people who first pioneered this concept are dead. Best of luck on your project, I have to admit, it is very cool. EMP proof memory since the 50's! wake up people!
 
wikipedia link
 

I'd suggest actually learning how magnetic memory works first, use Wikipedia and Google.
 
Then I'd suggest searching Google Patents for anything related to magnetic memory ... since the technology is so old, the patents have long expired and often those older patents contain useful information
 

lol, https://www.deezer.com/us/track/113826738?autoplay=true