First valve amplifier set
- Made:
- 1923
First valve amplifier set, assembled in suitcase, Marconi, 1923.
This was the first aid employing valve amplification. It incorporated a normal 2-stage low frequency amplifier, run by a 66-volt radio high-tension battery and an accumulator. It has a magnetic microphone and a single magnetic earphone. It weighs about 11 pounds.
Details
- Category:
- Sound Reproduction
- Object Number:
- 1951-681
- type:
- valve
- credit:
- Hearing Aid Manufacturers Association