Monaural/fm Receiver (Model Tdr-4)

Telex model TDR-4 monaural/FM receiver combines a complete body type hearing aid and an FM receiver in a single compact instrument. It is designed for use as either a monaural auditory trainer or as part of a personal FM system in conjunction with the user's audio input or telecoil equipped hearing aid. Design features as follows: Standard metal belt clip. Body harness with locking snaps. Ink erasable for student's name. Protected, flush-fitting, plug in channel crystal. High fidelity amplifier. One acoustically isolated environmental microphone. Automatic "no FM" indicator warns of FM signal loss. Automatic low battery indicator. Calibrated low cut and SPL trimmers. FM level trimmer boosts the FM signal up to 10 decibels as compared to the gain of the hearing aid section. Auxiliary input jack for use with television, tape recorders and other audiovisual units. Rechargeable with either a classroom size TC series charger or a jack type AC-1 charger. Can use AC-1 charger for operating power. Separate FM and hearing aid function switches, volume control, and balance control. Hi- average full on gain 66 decibels normal, 63 decibels wide, 70 decibels power response. Maximum gain 72, 68, 78 decibels. Reference test gain 56, 51, and 60 decibels. Frequency response, normal tone 50-5000 hz, 20- 6500 hz, 50-3700 hz, low cut 100-5200 hz, 50-6600 hz, 100-54700 hz. Equivalent input noise maximum 25, 28, 25 decibels. Battery operating time, FM and hearing aid, 11 to 14 hours. Hearing aid 25 to 33 hours. Size 2.3 by 1.13 by 3.75 inches. Weight with batteries, 6 ounces.