Ham Radio General Class Practice Test

Which of the following direct, fused power connections would be the best for a 100-watt HF mobile installation?

1. To the battery using heavy gauge wire

2. To the alternator or generator using heavy gauge wire

3. To the battery using resistor wire

4. To the alternator or generator using resistor wire

The correct answer is: To the battery using heavy gauge wire

For a 100-watt HF mobile installation, connecting directly to the battery using heavy gauge wire is the most effective choice. This approach ensures that the power supply is stable and can deliver sufficient current without significant voltage drop. Heavy gauge wire minimizes resistance in the circuit, which is crucial in preventing power loss and maintaining efficient operation of the transceiver. A direct connection to the battery allows for immediate access to the power source that can handle the transient demands of the radio during transmission. The battery has a large capacity and can provide the necessary burst of power without affecting the overall electrical system of the vehicle significantly. Connecting to the alternator or generator may seem beneficial as well, but during high-demand situations such as transmitting, the system might not provide stable voltage or current due to the alternator's own load management and current regulations. Also, using resistor wire is not advisable as it introduces resistance into the circuit, which can lead to insufficient voltage to the radio during operation and could negatively affect performance. Therefore, the safest and most reliable method for powering a 100-watt HF mobile installation is through a direct connection to the battery with heavy gauge wire.