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HarryA
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Posts posted by HarryA
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I use the Arduino UNO everyday. It is well supported on the internet at various forums. It is somewhat dated but a good beginners microcomputer. You can download the Arduino IDE 2.0 (integrated development environment ) from arduino.cc
The Arduino Cookbook in pdf format is available for download here: Arduino Cookbook
If you get an UNO also get the short blue cable; long cables do not often work well.
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By positive flank you mean on the rising edge of the pulse or the pulse top? What is the nature of the pulse train? Voltage and pulse rates.
"Need a circuit that can trigger a relay when movement or stop is detected on a axle." How does that relate to the pulse from the timer being on only 0.5 secs? Does that mean that if the pulse train is off for more than 0.5 seconds (axes stopped turning) the timer drops out resetting the relay?
A retriggerable timer would stay on while it is constantly being reset else if not reset after 0.5 secs its output would go low.
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For TTL logics datablade books see ebay.com
Or even better Forrest Mims's book "Engineer's Note Book !! - A Handbook of Integrated Circuits Applications" is available online in pdf from: IC Book
Dated but still the best book ever on ICs. The book has an NE555 circuit for missing pulse detection; which maybe what you need.
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Will the first circuit here do what you want to do?
I tried it in the simulator but I have not got it to work yet; poor connection 🤨
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You say: " one wanted the current to rise lowly from 5 volts to 10 volts each ten seconds," Is 5 volts off for the lamp?
Also you all say: "had its light intensity decreasing to zero volts:" That statement is confusing; which is going to zero the light intensity or the applied voltage?
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If you search on the internet for "Automatic electric bell using wifi "you will find numerous articles on the subject: like: https://www.youtube.com/watch?v=jkG9sUWc1CA
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What does not work? The LED fade or the mp3 player?
What do you wish the push button to do?
A: Push the button once and the LED fades on and off until you push it again.
B: The LED fades on and off while you hold the button down. Releasing it the fading LED stops.
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I am not sure what you need but here is code that fades a LED up and down. It does not block your code by using Delay(), You can paste it into your Loop{} or call it as a function. You may wish to play with the int period value and the +/-5 value. Do note which i/o pins you can use with this PWM code.
//use pins 3, 5, 6, 9, 10, and 11 on the UNO const int ledPin = 3; //whichevery pin you choose Do not forget the resistor! int period = 10; //how fast to fade the LED:100 = 1/10 sec. etc unsigned long time_now = 0; //have not read the time yet int brightness = 0; //start with LED off boolean IncreaseBrightness = true; //start with increasing brightness void setup() { pinMode(ledPin, OUTPUT); Serial.begin(9600); //you may have this; used here for testing } void loop() { // non-blocking delay if(millis() > time_now + period) //get current time and compare { time_now = millis(); //for next time //fade LED up or down if(IncreaseBrightness) { analogWrite(ledPin, brightness +=5 ); if(brightness >= 255) IncreaseBrightness = false; //max ouput to LED = 255 } else //must be decreasing brightness { analogWrite(ledPin, brightness -=5 ); if(brightness <= 0 ) IncreaseBrightness = true; //min ouput to LED = 0 } } //some code...testing displays values..... Serial.print("brightness "); Serial.println(brightness); } -
You could use a microprocessor that has a a/d (analog to digital) converter.
Use an op amp (operational amplifier) to increase 20mV signal for the a/d converter get reasonable results. -
I prototyped a couple of passive notch filter circuits including the one Tony posted. But neither were very good; two broad.
If I can find an inductor between 150 to 200 mh I will try a parallel resonant band stop filter.
This site maybe helpful: 8 Ways Of Resolving The Electric Guitar Feedback Problem
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What you need is a notch filter to remove only a narrow band of unwanted frequencies . There are pedal notch filters on the market but they are pricey. Search on "guitar notch filter pedal".
About half way down the page he covers guitar pedals.
If you wish to make one perhaps I could help you with it.
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It looks good to me. I would go with it. Are you building something interesting?
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Why not read books that interest you? For example:: Digital Design and Computer Architecture
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Perhaps you could convert the alternator output directly to dc without a transformer to 300vdc (or about) and use a 127-350 dc to 24 v dc dc/dc converter to get 24 volts.
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How about this? Without showing the resistors.
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I do not see the connections to relay's NC contacts for each LED. The red LED most get its current through the NC contacts of the Green LED's relay. And the green LED must get its current through the NC contacts of the red LED's relay. Thus when one relay is active the other LED can not receive current through the the now open NC contacts.
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Hello, I am not very knowledgeable on wifi routers so I can not offer much help. This web site maybe helpful:Improve Your Wi-Fi Speed in 10 Simple Steps
On my Frontier router if you type into the browser a certain number/code it brings up a rather sophisticated user interface which maybe helpful to you if you can find the code for your router.
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Perhaps a voltage comparator? See: Comparator
You could use the 12 volts to trigger a relay that supplies a voltage to the timer? The relay should require more than 10 volts to trigger the relay to avoid the rewind? It is not clear where the 0.0009 volt and 0.1 volt signal comes from.
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When a post is made the forum software often displays key technical words in the post description. This would suggest that one could use that software to detect post that are legitimate from others. Of course the the devil is in the details. Invision's Zendesk maybe open to support on something like this as it would also be to their benefit. When I had a forum (Simple Machine's software) I spent a lot of time mutilating the software to get what I wanted.
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Practical Electronics for Inventors is a good book. Used copies are available.
An online lab that is informative; you can download the pdf files from: Hunter College
Lots of free info on Youtube.com
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First off one can not read the text on the second IC. They claim fake ICs come in two types; those that are commercial grade and sold as military grade.
And those that are used from discarded equipment. The latter type may well have the correct text on them. I gather they do not manufacture fake ICs as they are too inexpensive to be bothered with.
Seeking Recommendations for Beginner-Friendly Microcontrollers - Emmanuel Katto Uganda
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Yes, I have had problems uploading with long cables. Never with the short blue cables. I see on Arduino forums others have problems unloading with longer cables also. One has to be aware some "USB" cables are for charging only; they lack the center two data contacts. You can look into the larger connector and see if there are 4 contacts or not.