Organize and Share your Electronics the way you want. Sign-Up for a free account now. It takes only 30 seconds!

Homebrew SWR meter for VHF, UHF and SHF (including Wifi ISM Band)

Homebrew SWR meter for VHF, UHF and SHF (including Wifi ISM Band)

The circuit on this page serves as a Voltage Standing Wave Ratio meter or VSWR meter for the VHF-UHF-SHF frequency range. This includes the Wifi (802.11b/g), 2m, 70cm and 13cm Radio Amateur bands.

When building antennes for the Wifi band (Like the 8dBi omni), a need for an easy way to check the antennas arrose. A Voltage Standing Wave Ratio (VSWR) meter useable at the 2,4GHz band is however, hard to find. Meters like the? Daiwa CN-801S are expensive and need a minimum of 500mW (27dBm) power to function correctly.

The device consists of two parts. One RF head and a (preferably analog) indicator. The meter has a 9 Volt alkaline battery power supply. The indicator on top is used to read the VSWR. The first switch is used to switch the power. A green low-current (2mA) LED illuminates when power is applied to the circuit.
The second switch is used to switch between slow (peak-hold) and Fast mode.

Below, the last control is the Sensitivity pot. It is used to adjust the meter sensitivity to the RF source used, such as a Wifi Access Point, or VFO. RF Input power must be somewhere between 15 and 20dBm (30 to 100mW)?

Visit Here for more.







 

More Articles to Read

Serial seven segment LED display shield
Serial seven segment LED display shield
G-code controlled drawing plotter
G-code controlled drawing plotter
An Arduino round word clock
An Arduino round word clock
The Sandwich-o-Matic will make your lunch automatically
The Sandwich-o-Matic will make your lunch automatically
Scalar Network Analyser Jr
Scalar Network Analyser Jr
An Arduino-controlled automated whiskey distillery
An Arduino-controlled automated whiskey distillery
The Rex800 looks like a dinosaur Terminator
The Rex800 looks like a dinosaur Terminator
Home Environment Monitor
Home Environment Monitor
Understanding the Operation of the Frequency Synthesizer in Maxim’s RF Transceivers
Understanding the Operation of the Frequency Synthesizer in Maxim’s RF Transceivers
App note: EPIC: Electro-Pyrotechnic Initiator Chip Resistor
App note: EPIC: Electro-Pyrotechnic Initiator Chip Resistor
Noisy ESP8266
Noisy ESP8266
App note: Noise analysis for high-speed op amps
App note: Noise analysis for high-speed op amps
Skill Sunday: Arrays
Skill Sunday: Arrays
App note: Infrared remote control implementation with MSP430FR4xx
App note: Infrared remote control implementation with MSP430FR4xx
Gesture Controlled Smart Home
Gesture Controlled Smart Home
Design for a Wideband, Differential Transimpedance DAC Output
Design for a Wideband, Differential Transimpedance DAC Output
Wrist thrusters let you fly through the water effortlessly
Wrist thrusters let you fly through the water effortlessly
Bertan/Spellman 225-20R HV power supply teardown
Bertan/Spellman 225-20R HV power supply teardown
Blinking Christmas Lights
Blinking Christmas Lights
Adjusting clock with alarm, hygrometer & thermometer on 1.8″ ST7735 display
Adjusting clock with alarm, hygrometer & thermometer on 1.8″ ST7735 display

Top


Shares