Summary of OFF-GRID RADIO ALSO REPAIRABLE OFF-GRID
The RFBitBanger is a QRP (low-power) amateur radio designed for off-grid use and repairability. Built primarily from through-hole, off-the-shelf parts with an ATMEGA328P microcontroller and optional PCB or perf-board construction, it supports CW, SSB, RTTY and a custom low-bandwidth digital mode called SCAMP. Single-band operation covers 20–80 meters via pluggable filters, prioritizing simplicity, maintainability, and field serviceability for Parks on the Air, Summits on the Air, or emergency use.
Parts used in the RFBitBanger:
- ATMEGA328P microcontroller
- Through-hole resistors
- Through-hole capacitors
- Through-hole inductors
- Pluggable band-pass filters (for 20–80 meters)
- Perf board or optional PCB
- Through-hole transistors
- Through-hole diodes
- Crystal or frequency reference components
- Connectors and wiring for off-grid power and antenna
- User interface components (switches, knobs, connectors)
Low-power radios, often referred to in the amateur radio community as QRP radios, have experienced a resurgence in popularity lately. Blame it on certain parts of the hobby become more popular, like Parks on the Air (POTA) or Summits on the Air (SOTA). These are events where a radio operator operates off-grid at remote parks or mountaintops. These QRP rigs are a practical and portable way to make contacts. You would think that a five- or ten-watt rig running on batteries would be simple. Surprisingly, they can be enormously complex and expensive. That’s why [Stephen] built the RFBitBanger, a QRP radio designed to not only be usable off-grid but to be built and maintained off-grid as well.
The radio accomplishes this goal by being built out of as many standard off-the-shelf components as possible. It eschews modern surface-mount components in favor of the much more accessible through-hole parts, including the ATMEGA328P at the center of the build. A PCB design is also available, but it can be built on perf board nearly as easily. The radio supports any mode a QRP operator might use, including CW, SSB, RTTY, and a new mode designed explicitly for this radio called SCAMP which is a low bandwidth, low SNR digital mode built into the Arduino-based firmware. It’s a single-band radio, but any band between 20 and 80 meters can be selected with pluggable filters.
As far as bomb-proof radios go, we can’t imagine a better way to live out an apocalypse than with a radio like this. As long as there’s a well-stocked parts drawer around, this radio could theoretically reach around the world without worrying about warranty claims, expensive parts, or even a company going out of business or not stocking parts for old radios anymore. There’s also more information about this build at the Open Research Institute for those interested. And, if you’re wondering how useful any radio could be using only five watts of transmitter power, take a look at this in-depth look at QRP radio operation.
Source: OFF-GRID RADIO ALSO REPAIRABLE OFF-GRID
- What is the RFBitBanger designed for?
It is designed for off-grid use and repairability, using standard through-hole parts so it can be built and maintained off-grid. - Which microcontroller does the RFBitBanger use?
It uses an ATMEGA328P microcontroller. - What operating modes does the radio support?
It supports CW, SSB, RTTY, and a custom digital mode called SCAMP. - Can the RFBitBanger be built without surface-mount components?
Yes, it is built primarily from through-hole components and can be assembled on perf board. - Is there a PCB available for the RFBitBanger?
Yes, a PCB design is available, though perf-board construction is also possible. - What frequency bands can the RFBitBanger operate on?
It is single-band but any band between 20 and 80 meters can be selected using pluggable filters. - What is SCAMP?
SCAMP is a low bandwidth, low SNR digital mode implemented in the Arduino-based firmware for this radio. - Why choose through-hole parts for this build?
Through-hole parts are more accessible and easier to source and repair off-grid compared to modern surface-mount parts.
