main beam dimmer - headlight dimmer/dipper

main beam dimmer elektor february 1983 Every motorist is occasionally dazzied by oncoming vehicles that fail to dip their headlights, and the results can be dangerous. But the culprit has his problems too. If he suddenly dips his headlights he will see as little as the driver who is dazzied. It would be better if his eyes could adjust to the new situation more gradually. Even this problem has an electronic solution: dimming/dipping in stages with the main beam dimmer. main beam dimmer headlight dimmer/dipper How does this main beam dimmer operate? Figure 1 clarifies the situation. Until the instant of dipping (to) the full battery voltage is applied to the two headlight bulbs. When the dipswitch is actuated the bulb voltage drops by about 4 V, clearly indi- cating that the main beam has been removed. The bulb voltage then continues to drop, so that headlight brightness decreases. Finally, tmax is reached — the instant at which the main beam is fully switched off — and only the...