Hammarlund Built the Best Ham Radios — Then Made One Bad Call

In 1910, a Swedish immigrant named Oscar Hammarlund opened a small manufacturing shop in a Manhattan loft. Within two decades, his variable capacitors and radio kits had become industry standards. By World War Two, nearly ninety percent of all American electronic military equipment relied on Hammarlund components. The SP-600 receiver became the benchmark for military and commercial operations worldwide, and amateur radio operators considered Hammarlund the gold standard. Then, in the late 1950s, one decision set off a chain of events that no amount of engineering brilliance could reverse. A company that had survived two world wars, built equipment for the Navy and the FAA, and dominated its industry for half a century was gone within fifteen years. This is the full story of Hammarlund, from a Fulton Street loft to the empty factory in Mars Hill, North Carolina.