Elektor Team (9510)

1-07-1985 | Infra-red light barriers enjoy great popularity as timing devices at sports venues, as detectors in alarm instal- lations, as optoelectronic...

1-07-1985 | It is sometimes required in certain cir- cuits that are powered from just one battery to derive a negative supply voltage from the positive...

1-07-1985 | This little unit may be used to give an audible alarm when, for instance, a washing machine hose has burst, or when it starts to rain so you...

1-07-1985 | In contrast to the other metal detector in this issue, the present one works on the principle that the frequency of an LC oscillator changes...

1-07-1985 | a delayed trigger pulse or an .external trigger input. None the less, the com- parator remains an almost indispens- able aid in the testing...

1-07-1985 | An appreciable part of short-wave radio traffic takes place via morse and radio teletype transmission. To ensure optimum reception of these...

1-07-1985 | elektor july/august 1985 1110111B.111 moitigie Which amateur film maker has not wished sometime that he could experiment with time exposures...

1-07-1985 | All types of operational amplifier can be functionally checked with the tes- ter proposed here. The principle of the tester is quite simple:...

1-07-1985 | Many electronics hobbyists have crystals lying about, but don"t know whether these are still working all right. The crystal tester described...

1-07-1985 | elektor july/august 1985 before make. Unfortunately, tran- sistors have the property of switching on much faster than switching off. For exa...