Battery Runtime Calculator — Partisan Comms Group
Battery Runtime Calculator
Estimate Portable Radio Operating Time
"How long will my battery last?"
Actual battery runtime depends on several factors including battery capacity, transmitter power level, receive current draw, and how often the radio is transmitting. This calculator provides an estimated operating time based on your equipment and operating style.
Results are estimates only. Actual runtime will vary depending on battery condition, temperature, operating mode, and equipment efficiency.
Safety Notice
Do not discharge batteries below manufacturer recommendations. Excessive discharge can damage batteries, reduce lifespan, and create unsafe operating conditions.
Calculate Runtime
Preset value for SSB. Select "Custom Duty Cycle" to adjust manually.
Typical Amateur Radio Operating Profiles
| Mode | Typical Transmit % |
|---|---|
| Monitoring Only | 1–5% |
| Casual FM Repeater Use | 10–20% |
| SSB Voice Operations | 20–30% |
| CW Operations | 30–40% |
| POTA Activation | 25–40% |
| SOTA Activation | 25–50% |
| Digital Modes (FT8 / JS8Call) | 50–100% |
| Emergency Net Operations | 15–40% |
Typical Current Draw Examples
| Equipment | Receive | Transmit |
|---|---|---|
| Handheld Radio | 0.2A | 2A |
| Mobile VHF/UHF Radio | 0.5A | 12A |
| 50W HF Radio | 1A | 10A |
| 100W HF Radio | 1A | 20A |
| QRP HF Radio | 0.3A | 2–3A |
Always verify actual current draw using manufacturer specifications or direct measurement.
Battery Technology Overview
LiFePO4
- —Lightweight
- —Long cycle life
- —Excellent for field operations
- —Can safely use most of rated capacity
AGM Lead Acid
- —Lower initial cost
- —Heavier
- —Best when discharge remains above 50%
Sealed Lead Acid (SLA)
- —Common and inexpensive
- —Heavy
- —Reduced lifespan if deeply discharged
Planning Portable Operations
For portable operations such as Parks on the Air (POTA), Summits on the Air (SOTA), emergency communications, and off-grid deployments, battery planning is just as important as antenna planning. Understanding expected runtime helps operators:
- —Select the proper battery size
- —Reduce carried weight
- —Improve mission duration estimates
- —Prevent unexpected power loss
- —Build more reliable field stations
Accurate battery planning helps ensure your station stays on the air when it matters most — whether you're activating a summit, running a net, or supporting emergency communications.