Mobile Phone diagram | Next Electronics

Upon acquiring the car, it was appreciated that it did not emit a "chirp" or sound the horn each time the doors were locked or unlocked. There are occasions when discreetness is preferred regarding entering or exiting the vehicle. However,...

building rf remote control

The simplest approach to creating a remote-controlled robot is to repurpose a low-cost wireless toy car by removing its receiver module and remote control. Alternatively, one can design a custom RF remote using an ASK (Amplitude Shift Keying) based transmitter/receiver...

DF data transmission module and the super-regenerative receiver module

The DF data transmission module operates at a frequency of 315 MHz and utilizes a surface acoustic wave (SAW) resonator for frequency stabilization, ensuring high frequency stability. The frequency drift remains minimal, at only 3 x 10^-6, across a temperature...

RF OSCILLATOR CIRCUITS

A widely recognized circuit is the Hartley oscillator, which is characterized by a tapped coil within the LC tank circuit. The tap point of the coil is grounded. The oscillator's amplifier section functions as a common-emitter amplifier, resulting in the...

Wide Dynamic Range Field Strength Meter

A field strength meter is a useful tool for locating a transmitter. However, a sensitive field strength meter has limitations: it responds to nearly any RF signal entering its input. This characteristic reduces the effective sensitivity of the field strength...

RF Inductance Meter

This RF inductance meter measures RF chokes in the 500 nH to 50 µH range. A simple solution was required to measure hand-wound RF inductors in a secondary lab setting. The user intended to utilize this device occasionally and did...

RF Actuated Keying Monitor

Sending Morse on a rig without a sidetone is not impossible, but is not particularly pleasant either. This battery-powered monitor has been designed to provide an audible indication of keying for those whose rigs lack a CW sidetone. Its sensor...

Four Foot Box Loop Antenna

Please find attached your copy of my four foot unamplified box loop. It will tune from 525 kHz to about 1710 kHz covering the entire Broadcast Band. The umbrella stand described in the article is the type you would use...

Carport wireless alarm circuit a

The alarm circuit is composed of two main components: the transmitter and the receiver. The transmitter circuit, as illustrated in Figure A, features a smoke break reed switch labeled GT. When a magnet approaches the GT, the internal contacts open....