Here has been presented the simple logarithmic surveyor light. Honours him simplicity, bargain price, is improved the temperature stability. Trimer adapts the exit level for the complete dark (approximately 1V). For the minimal temperature dependence at the determined illumination necessary trimer offset that then the exit gives 2,5V. As necessary the trimer was able will make an exchange and with the lower trimer.
The obtained exit voltage then was able analogic to cultivate these easily stood to gain the passive detector of movement which detects the change on accepted bright. Condition is that exist some illumination of space. Transfer shades across the detector was able easily to notice in the whole dynamics illuminations because the complex is performed finding the logarithm of the measured intensity and relative changes of intensity of lights give the invariable amplitudni jump. With the resistor 1M adapt the reinforcement of change of light, and with 10K adapts the necessary amplitude for the activation of exit (1K..1M)
If the exit voltage of basic complex directly join in two are left invertors CD4069, then at lights greater from will adjust will change the logical state his output in high (i.e. can get the low cost comparator bright scheme down). Advantage schemes are not the use of the more expensive rail this rail operation amplifiers (who get rid of problems in the dynamics of the entry and exit signal when they reach voltages power supplies) these in the wide dynamics adjustings and relative same sensitivities of adjustings during the any illumination. Resistor 2M2 determines hysteresis the comparator. Without cares comparator there is no hysteresis.