The RFBitBanger is an off-the-grid QRP radio. It is not just designed to be used off the grid, it is designed to be assembled and maintained off-the-grid. Most radios require specialized parts that would be difficult to obtain in an extreme parts shortage or in remote places. This radio is designed to be assembled and maintained using the most common jellybean components that might be in a hobbyist junkpile. It will mainly support low bandwidth/digital modes to make the most of limited power.

This is a single band double-sideband radio, with the band changed by pluggable external filters on 20 m to 80 m. A double-balanced ring mixer is used to provide good rejection of strong stations while not requiring any custom ICs such as SA612 or FST3253. The mixer has strong drive to reduce nonlinearity. The radio is made from readily available through-hole parts which are widely available and have multiple vendor alternatives. The parts needed are very common so that cheap spare parts can be stockpiled or scrounged from other equipment so that the radio may be more easily maintained in off-grid conditions. The includes ATMEGA328P/Arduino Nano, LM358 op-amp, LM386 audio amplifier, 2N7000 MOSFETs, 2N3904 NPN transistor, SS8550 PNP transistor, and a HD44780 display. It can use a SI5351A frequency synthesizer IC soldered to the board, or a plug-in SI5351A development module. There is a MS5351 workalike for this IC as well. Ferrite cores are needed for transformers/chokes which can be easily bought (FT50-43) or scrounged as EMI suppression beads from cables.