DIY Voice Intercom using WLAN

by TuxMan

I would like to build two devices to communicate within my own WLAN via speech based on Arduino, RasPi, ESP32 or similar. Does anyone know a project I could use? Any hint/link, etc. is welcome. I can design the housing, but my skill on the mentioned boards is not good enough to design the electronics myself.

An example for what I mean is this one:


But for my purpose it seems too complicated. I just want to make short calls like "Please come over for dinner" ... "Just give me another 5 minutes" … "Would be bad, dinner is already served" …. ;-)

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Bluetooth module for keychains?

by UncleJohn42

I'm modeling and printing custom keychains. I would like to be able to locate them with a smartphone. Can anyone point me in the right direction?

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Can't register SIM card on GSM Module (SIM800)

by abasel

I am using the following quickstart guide: https://www.ayomaonline.com/programming/quickstart-sim800-sim800l-with-arduino

I have tried different sim cards (confirming that they work by testing them in a mobile phone) but I cannot get them to register on the SIM800 module.

This is the module that I am using: https://www.aliexpress.com/item/SIM800L-V2-0-5V-Wireless-GSM-GPRS-MODULE-Quad-Band-W-Antenna-Cable-Cap/32877115526.html

The following are the AT commands and outputs:
+COPS: (3,"VODAFONE","voda NZ","53001"),,(0-4),(0-2)

+CFUN: 1

+CREG: 0,0

I have checked the power supply and and that the SIM is plugged in correctly. Any other ideas?


Arduino_Uno GSM sim800
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why is frequency of neopixel signal faster than PWM of the Arduo

by SavageRodent

hay guys.

i was playing around with an oscilloscope and decided to compare the wavelength the neopixel data sinal with that of the PWM at, what i thought should be its highest possible frequency?

I'm using an arduino uno for the neopixel signal and a arduino nano to run the a sketch (see below) for the PWM. Both boards have 16Mhz clock speed so i assumed that wouldn't be a factor.
Anyway, as u can see in the picture the neopixel data sinal (blue line) is at a much higher frequency the the PWM (yelow line).

My question is, why is this?

//PWM code
void loop() {

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Missing .ino file in Marlin

by fordtek1

Hello. I'm trying to reconfigure my printers after a hard drive failure and when trying to download the 1.1.9 marlin files, the .ino file is not present in the download. Has it been relabeled or do I have a corrupt download? ANy and all help is greatly appreciated

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Mini cnc GRBL router

by cncjim4

Anyone here have a inexpensive mini cnc GRBL router that the use to make PCB boards. If you do which one did you buy and how did it work out?

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Wrong Driver for Atmega2560

by 3DPDude

Hi everyone!

I got this: https://www.amazon.com/BIQU-control-upgraded-controller-Printer/dp/B07CT9VMSV/ref=sr_1_1?ie=UTF8&qid=1545836542&sr=8-1&keywords=Tango+controller+board as an upgrade for my atmega2560 Rumba board. It was working great, it showed up in device manager as the atmega2560, and I could upload firmware to it. But now, it all of a sudden showed up as CP2102 USB to UART device, and I can't figure out how to upload firmware to it.

Any suggestions?

Thanks guys!

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what determines a stepper motor's voltige?

by SavageRodent

hay guys.
i've been browsing ebay for Nema-17 stepper motors, for a future project. The motors i'm looking at are all of a similar size
but have big differences in specification. I'm struggling to understand the relationship between the inputs and outputs.
Below are few key details for a couple of motors i looked at. Motor 2 has far higher voltage, draws twice the the current and yet has practically the same holding torque. can someone please explain this to me?

motor 1:
38mm length
0.4N.M Holding Torque

motor 2:
40mm length
12 V, 24 V
45Ncm Holding Torque

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Looking for a good inexpensive Soldering Iron

by cncjim4

Right now I am using a cheap Wall Lenk L25 soldering Iron. I am looking to buy something a bit better. I don’t want to spend a lot of money on something that is use for my hobby. I am looking at the Weller WLC100 40-Watt Soldering Station Amazon has it for about $38.00. What do you people recommend for a good inexpensive Iron .

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