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Return to BlogSWR Meter with LCD Display
Posted Jan 24, 2012 at 2:46 pm
Figure 1
The project was based on a PIC16F877A microcontroller for the basic purpose of encouraging radio amateurs to build their own SWR meter at a very cheap price compared to high-priced ready made.
Two double-sided PTH boards were used to develop the project. The LCD, regulator, and backlight controllers are located on the first one which is the CPU board. Pure DC level is being received by this board from sensor board for calculation and display. The RF sensor bridge is the second board where the power from the transceiver comes in and goes out to antenna. It contains a simple HF toroidal bridge using BAT85 diodes.
The SO239 types of connectors are used but the N-type connectors can also be used since they will fit nicely on the four mounting holes available for SO239 sockets. The meter and bridge will work very well at a KW and above on all bands although it is rated at 100W HF. Since the display unit firmware is limited to 100W maximum, a measurement of 1KW can be set on the bridge presets. Compared to the commercial SWR meter, the readings on this device were very accurate.
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2 years ago: Interesting article, but where is the rest of the story? The link at the bottom redirects only to an image file...