Megáfonos son amplificadores de sonido portátil, destinados a la amplificación de la voz de una persona. Se utilizan en sistemas de aviso, situaciones en las que se desea dar órdenes o orientación para muchas personas, torcidas, etc. En la figura 1 tenemos un ejemplo de megáfono común. Algunos tipos, en lugar de altavoces comunes utilizan las cornetas acústicas.
La alimentación normalmente se realiza a partir de pilas o baterías y la potencia es del orden de algunos vatios.
Encontramos este circuito en una publicación inglesa de 1980. Memoriza el pico de la señal de...
Este circuito es de una Popular Electronics de octubre de 1981. El circuito indica la polaridad de la...
El sensor de este circuito, de una documentación antigua, no es más que un micrófono de electreto....
| Joomla! Version | 5.2.3 |
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| Template | cassiopeia |
| Database |
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