Military Type P/O H-87A/U. Four single conductors, rubber jacket. Protected at junction of single and two conductor cordage by rubber molding. Leads terminated with terminals. Rubber molding is bonded to terminals and cordage to form a waterproof rubber covered connection to the earphone. Main cable is rubber jacketed. Terminated by transformer plug. Shell of plug is protected by rubber molding. Plug in Military Type PJ-054.
TRANSFORMER: Isolating impedance matching type. Capable of transferring audio frequency energy from 600 Ohms source to a 7.5 Ohm load. Frequency Response: 200-6000 CPS Impedance: 600 Ohms Per MIL-C - 18266A
EARPHONE: MODEL 10301A
Military Type H-87B/U Type: Dynamic Frequency Response: 100-7000Hz Sensitivity: 103db @ 1KHz re 1 mW RMS Impedance: 15 Ω @ 1 kHz Distortion: <5% from 200-7000 Hz Altitude Compensation: 50,000 feet Temperature Range: -55'C - +85'C Per MIL-E-18239
