Walker Ameriphone XL-30 Operating Instructions Manual page 27

Specifications
Maximum gain
High frequency (3kHz): 30dB
Wide band (300 to 3000Hz):
20dB
Tone control range
Full range: 300 to 3000Hz using
one slide control.
Dimensions
1 1
Size: 9 /2" x 7" x 3 /4"
Weight: 2.52 lbs.
Power Requirements
One 9 Volt alkaline battery for
ring flasher operation only. (not
included)
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