In his Power Tool Batteries for Portable or Emergency Operations article (a free preview from the July 2024 issue of QST Magazine), Gordon S. Novak, AF5KA, demonstrates how inexpensive DC–DC convertors can turn easily accessible lithium power tool batteries into a good backup or portable source for powering a radio.
This is a very timely and topical discussion in light of RRRA’s July Portable Operations July Activity.
AF5KA begins with a brief discussion of the DC–DC convertor specifications to look for as well as two types of battery connections: ad-hoc (using ATC fuses) and brand-specific plug-in connectors.
AF5KA then discusses power limitations, provides examples of battery sizes for different power levels, and mentions the easy-to-remember rule of thumb: “the maximum amperage to the radio is three times the ampere-hour rating of the 18V tool battery.” 1
TL;DR; “Almost any power tool battery will power a QRP radio. An 8Ah battery at 18 V will power a 100 W transceiver.” 2
AF5KA’s article closes with a list of seven power tool battery advantages and a link to information on where to purchase some of the parts mentioned in the article.
“Power Tool Batteries for Portable or Emergency Operations”, ARRL The national association for Amateur Radio, accessed June 6 2024, http://www.arrl.org/files/file/QST/This%20Month%20in%20QST/2024/07%20July%2024/0724%20Novak%20free%20article.pdf. ↩︎
“Power Tool Batteries for Portable or Emergency Operations”, ARRL The national association for Amateur Radio, accessed June 6 2024, http://www.arrl.org/files/file/QST/This%20Month%20in%20QST/2024/07%20July%2024/0724%20Novak%20free%20article.pdf. ↩︎