4 Pack High Impedance Piezoelectric Crystal Earphones, Bare Leads

At the workbench, four matching earpieces support projects that use piezoelectric technology with crystal radios or transistor radios. Each earpiece uses a brass diaphragm with soldered wire connections for a direct path into a compatible project circuit. A black twisted cable runs 42 inches from each earpiece and finishes with bare leads that come pretinned for bench connections. A 20,000ohm impedance suits circuits that call for a highimpedance earphone instead of a standard lowimpedance type. Its resistance measures more than 20,000,000 ohms, so compare this value with your circuit design before connecting the bare lead. For circuit checks, capacitance measures 15,000 pF, while sensitivity at the 1 kHz test frequency reaches 57 dB. When selecting an earphone for a specific project, match its listed output range of 200 through 8,000 Hz. Crystal radio builders can connect the pretinned leads where their design requires a piezoelectric earpiece without a plug. Confirm compatibility with the bare leads and 20,000ohm impedance before placing an earpiece into transistor radio service. With four separate earphones, the pack supports several builds or replacements while keeping the same electrical values. Pretinned ends simplify preparation for a compatible terminal or solder point, but confirm your planned connection first. These earphones end in bare wire rather than a plug, so plan an adapter only if your project connection calls for one. Soldered wire joints and the brass diaphragm define the construction, helping you compare this earpiece with project needs. Before wiring, verify the exact circuit requirements for impedance and capacitance, then check its lead style and frequency range. This product is not a toy and is designed for use by teens and adults ages 13 and up