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Could be an ear trumpet, or a crystal radio which does not require batteries to receive AM and power a small speaker or headphone... http://en.wikipedia.org/wik
by patrickgzill 16y ago
Could be an ear trumpet, or a crystal radio which does not require batteries to receive AM and power a small speaker or headphone... http://en.wikipedia.org/wiki/Crystal_radio http://en.wikipedia.org/wiki/Crystal_radio
- ars 16y agoIt's 1928, radio was far from widespread, and crystal radios were much larger than that.