| 摘要 |
An automatic power control device comprising a passive, non-linear voltage detector controlling a series bipolar transistor regenerative latch circuit, acts to connect the load to a power source only when the voltage obtainable from the power source is sufficient to prevent improper ambiguous operation of the load, and further acts to disconnect the load from the power source when its voltage declines to that range which could result in ambiguous and/or erroneous operation. An electronic thermometric digital display instrument is shown, powered solely by a miniature solar panel. The instrument is amply powered, and the display is legible, even in dim light. Operation at lower levels of light is available with an economical auxiliary battery that is cut out of the circuit at when the light is as little as 5 lux. |
