Antonio Alfinito / I2TZK
Dziurda / K7SFN
Gajjar / VU2FD
Dual Channel LCD SWR Meter SWM2
and SWM3-USB were a great
success. Hundreds of Radio amateurs built it these projects with success. With more
and more feedback pouring-in and many demanding an SWR Meter
exclusively for QRP users, 10W range, USB/Battery Powered, etc, Tony/I2TZK decided to
go for a scale down version of PIC18F4550 for this project.
SWM3-QRP is an USB or Battery Powered CPU. Based
on Microchip's PIC18F4550 40DIP Chip, all what that we require is
single PIC Microcontroller.
This new QRP SWR Meter is developed keeping in mind
demand of QRP operators looking for a small, power efficient, stand
alone SWR meter for 10W class HF Radios. This project fulfills that
At present, only HF bridge is tested and
supplied with kits but there is a special space left on main board
to accommodate future expansion of a VHF bridge.
Firmware for SWM3-QRP Dual channel LCD
SWR Meter presented here is developed by Antonio
Alfinito / I2TZK for the ham community which is basically, a
scaled down version of full SWM3 -USB firmware. Tony has removed
following capability of original firmware to match this hardware: 1.
No PC Connectivity 2. No Configuration
of PIC Parameters thru PC
Purpose of this project is to
encourage radio amateurs to build their own SWR Meter at a low
PIC 18F4550 Firmware V1.0 for SWM3-QRP has:
is developed on Three Double-Sided PTH boards. The first one is CPU
board where LCD, Regulator, Battery, HF Bridge and Back Light Controllers are located.
This board is powered by 5V from either USB or internal 9V battery.
second board is HF Balanced Bridge. Its a simple Dual Hole Core type
passive balanced bridge for 10W.
Third board is for Front panel push buttons and
ON/OFF and USB/Battery Switches.
BNC PCB Type of connectors are used for HF and
there is a place available for second pair of BNC for future
addition of a VHF Bridge.
is intended for experienced Radio Amateurs.
rated at 10W HF, this meter & bridge may work at higher RF
Power. There is always a possibility to flash SWM3
firmware into SWM3-QRP PIC to get PC connectivity and ability to
configure this CPU for your own specific purpose.
A simple powder coated case for this
project is supplied with kits.