How many watts of power does it take to talk to Japan from California on ham radio?

Answer

Depends on many factors. What frequency are you talking on, what are the atmospheric conditions like, how good is your antenna, are you sending code or trying to talk voice, how good is the other ham's receiver, etc.

I can tell you that when I first received my license in the mail, my first contact on ham radio was with a ham in Arizona. I was in San Luis Obispo, CA. He was running 1/4 watt of power, using Morse Code (or, CW, as we call it, for Continuous Wave).

There are hams that have talked with countries all over the world using less than 5 watts of power. This question cannot be answered with a simple number - there are way too many variables involved.

Answer

Here are some factors to take into consideration:

The more sensitive the receiver is, the less sensitive the transmitter must be to transmit a signal. The opposite is also true.

The lower the frequency, the farther the signal can travel due to the wavelength. Lower frequencies tend to be less stable than higher frequencies. Higher frequencies cannot transmit as far.

First answer by ID1198298242. Last edit by Mik3ca. Contributor trust: 231 [recommend contributor]. Question popularity: 135 [recommend question]