Making actual measurements

For those unfamiliar with this type of power meter, there are two types of measurement you can make. The first and by far the easier is the direct-connect method. This is the one I used when doing the calibration. One simply connects the meter to the RF source with a cable. At one point, I had access to high-end equipment and was able to measure the loss in the test cables that I used. For this project, that kind of precision is probably not necessary, except at higher frequencies.

The second type of measurement is off-air measurement. In this case, an antenna and various filters are used. Probably, the single most important component in off-air measurements is the calibrated antenna. These antennas can range in price from tens to thousands of dollars.

Tip

The antennas that I will be using in this book are available on eBay for about $20 to $30 at http://stores.ebay.ca/KB5UBE-Engineering/About-KB5UBE-Engineering.html.

They come with calibration information in the form...