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Calculator Hub › Ham Radio Power & Portable Calculators

Ham Radio Power & Portable Calculators

Eight power and portable calculators for amateur radio: battery runtime, solar charge time, LiFePO4 vs SLA comparison, watts to dBm, QRP field day power budget, DC voltage drop, fuse rating, and PWM/MPPT solar controller sizing.

8 calculators
QRP & Portable
Runs in browser
1 — Battery Runtime

Battery Runtime Calculator

Operating time from battery capacity, average current draw, and depth of discharge. Covers LiFePO4, SLA, and NiMH chemistries.

2 — Solar Charge Time

Solar Panel Charge Time Calculator

Time to recharge a battery from solar, accounting for panel output, peak sun hours, charge controller efficiency, and battery state of charge.

3 — LiFePO4 vs SLA Comparison

LiFePO4 vs SLA Battery Comparison

Side-by-side weight, usable capacity, and cycle life comparison between LiFePO4 and SLA batteries for a given capacity requirement.

4 — Watts to dBm

Watts / dBm / dBW Converter

Full power unit conversion with reference table. Useful for QRP power budgeting and comparing TX power levels.

5 — QRP Field Day Power Budget

QRP / Portable Power Budget Calculator

Full power budget for a portable or Field Day operation: TX power, RX current, accessories, battery requirement, and estimated runtime.

6 — DC Voltage Drop

DC Voltage Drop Calculator

Voltage drop and power loss in a DC feed cable. Shows required wire gauge to keep drop below a target percentage.

7 — Fuse Rating

Fuse and Circuit Breaker Rating Calculator

Recommended fuse size for a given load current and wire gauge. Includes Anderson Powerpole and standard automotive fuse size recommendations.

8 — PWM Efficiency and Sizing

PWM / MPPT Solar Charge Controller Sizing

Required charge controller current rating for a solar array. Compares PWM and MPPT efficiency for your panel and battery voltage combination.

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