Simple TV Transmitter Circuit Using LM1889n IC

This is a design circuit for a simple TV Transmitter Circuit Diagram and Circuit Board using LM1889n IC. This is the figure of the circuit;

The LM1889n consists of a sound subcarrier oscillator, chroma subcarrier oscillator, quadrature chroma modulators and RF oscillators and modulators for two low-VHF channels.

Simple Pressure Sensor Circuit

Here’s a design circuit for a Simple Pressure Sensor Circuit Diagram and the PCB Layout. This sensor is based on the Lucas Nova Sensor NPC-410 Series pressure sensor. This is the figure of the circuit;

This circuit design utilizes an LM358 IC. The LM358 consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages.

Field Strength Meter Circuit

Here’s a design of the instrument that is very useful for radio frequency (rf) engineer and hobbyist, especially when he/she has to adjust the final rf transmission. Setting up an antenna impedance matcher is one of the examples. This is the figure of the circuit;

The circuit uses only one transistor (MPSA18) as the active component. The signal strength meter display uses analog meter (1 mA full scale). This rf field strength meter has no absolute scale if we don’t calibrate the scale using a standard instrument, but the important thing for this un-calibrated rf meter is that it can display the changes of an rf field when we calibrate the antenna or the matching network for the rf transmitter-antenna loading. If we are tuning the antenna size or the transmitter-antenna matcher filter, then just observe the analog meter to get the maximum deflection.