Start here: Emergency HF power planning begins with measured receive and transmit loads, duty cycle, operating hours, battery limits, charging sources, connectors, fusing, monitoring, and a reserve for degraded conditions.
Picture the operating situation
A 100-watt radio label does not describe station energy use. Measure current in the actual mode and power level, include accessories, and distinguish continuous operation from scheduled nets or listening watches.
Use this sequence
- Measure or verify radio and accessory current at operating voltage.
- Build a duty-cycle estimate from the actual mode and net schedule.
- Size usable battery energy with temperature, age, and reserve margin.
- Fuse each source appropriately and standardize protected connectors.
- Test charging and station operation together for noise and thermal problems.
Common ways the plan fails
- Using nominal amp-hours as fully usable capacity.
- Ignoring low-temperature battery behavior.
- Running an untested inverter or solar controller beside the receiver.
- Charging incompatible battery chemistry with the wrong profile.
Operating boundary:
Follow current license conditions, land or facility rules, the active communication plan, and the responsible organization’s directions. Keep antennas and supports away from power lines and uncontrolled public access. Do not self-deploy to an incident.
Primary source
Rules and response doctrine change. Confirm the current requirement at FEMA NIMS and ICS toolkit before relying on this guide.
