Matrix Membrane Keyboard 4x4 Modulo

This module is a perfect wireless switch to control all kinds of appliances and lights from your mobile phone or your voice assistant like Alexa or Google Home.

Sonoff SV makes all your appliances smart. As long as your mobile has a network, you can switch your appliances on or off remotely from anywhere at any time. You can automate routines by setting schedules for the appliances, which will make your day-to-day life easier and more convenient. The free eWeLink application allows you to control your devices easily.

Buzzer alarm to convert electrical signals into intermittent acoustic signals in robotic devices and Arduino projects

A buzzer with a pulsating tone generator, after connecting the supply voltage (DC) in the range of 3V -24V, the buzzer generates an intermittent signal with a frequency of approximately 1 Hz. Application example: as a reverse alarm system for a car. 

SIM808 GPRS GSM GPS Bluetooth SIM Quadband features:
- SIM card SIM808 GPRS GSM GPS Bluetooth SIM
- Supply voltage range: 3.4-4.4V
- Four bands GSM 850/900/1800 / 1900MHz
- GPRS multi-slot class 12/10
- GPRS mobile station class B
- According to GSM phase 2/2 +
- Class 4 (2 W at 850/900 MHz)
- Class 1 (1W at 1800 / 1900MHz)
- Control by AT commands (3GPP TS 27.007.27.005 and enhanced AT Commands from SIM Com)
- Operating temperature: -40 to + 85 ° C
- PCB dimension: 38x38mm
- GPS sensitivity
- Tracking: -165dBm Cold start Sensitivity
- Cold start: -147dBm
- Time to first solution
- Cold start: 30 s
- Start to warm up: 28s
- Already hot: 1s - Accuracy

This module is a three-way switch (COM, NO and NC) that uses the intensity of the ambient light to directly control the output load. Its adjustment potentiometer allows you to change the sensitivity and set the threshold for starting the relay. The relay is energized when it is darker than the threshold.
The optical isolation relay effectively protects the chip and ensures better performance.
This module is used for light detection, brightness detection , control of lamps and automatic equipment. Characteristic: - Channels: 1
- Supply voltage: 12VDC
- Output load capacity: 250V 10A AC / 30V 10A DC
- Relay activation current: & gt; 100mA
- Insulation: Yes
- Indicator LED: Green and Red
- PCB size: 5x2.6 cm / 1.96x1.02 "

USB DC 5V Bluetooth Audio features:
- You can connect it with your smartphone
- Power: DC 5V micro USB
- Speaker: 4 ~ 8 Ohm - Audio Jack: 3.5mm
- SD card: support MP3 / WMA / WAV / FLAC format
- The transmission distance could be up to 10m
- Size: 50 x 40 mm

The adaptor for the well-known ESP-12 and ESP-12E module

W1209 DC 12V Thermostat + Transparent Box Temperature Controller features:
- Model: W1209
- Supply voltage: DC 12V
- Temperature control mode: ON / OFF
- Temperature range: -50-110 ° C
- Resolution: 0.1 ° C range -9.9 ~ 99.9 ° C, above is 1 ° C
- Measure accuracy: 0.1 ° C
- Refresh rate: 0.5s
- Temperature protection 0-110 ° C
- Static current: ‰ ¤ 35mA, working current ‰ ¤ 65mA
- Output power: 10A relay
- Probe sensor: NTC (10K 0.5%) Waterproof Sensor
- Environmental requirements: -10 ~ 60 ° c Humidity 20% -85%
- Dimensions: 48 x 40mm

- Bluetooth 4.0 AT-09 BLE Master / Slave module with 6-pin connection base
- This module is very similar to HM-10 module
- Bluetooth protocol: Bluetooth V4.0 BLE specification
- Ultra-low power consumption, in 90uA standby mode
Wireless Module AT-09 Bluetooth 4.0 CC2541 IOS BLE features:

- Chipset based on CC2541
- Bluetooth Class 2
- Industrial level Bluetooth module SPP
- Flash 256Kb
- Integrated chip antenna
- Power supply: + 3.3 VDC 50 mA
- Working temperature: -5 C to + 60 C
- Operating frequency: 2.4 GHz ISM Band
- Modulation method: GFSK (Gaussian Frequency Shift keying)