The old radio receiver was connected to an antenna - a long electrical wire that was stretched on the roof of the house. Lightning affects the reception and a lightning strike on the antenna is a danger. The article published in the Haaretz newspaper in 1936 sheds light on the subject from a scientific and practical point of view.
The article was published in the radio page section of Haaretz newspaper, on 27.12.36. It was a few months after the start of operation of the mandatory "Voice of Jerusalem" - the first official radio station in the Land of Israel. The title of the article was: "Caution! Danger of lightning!” And its author - Shaul Mizel. We copied the article as it is and added a little linguistic and technological commentary.
Most European broadcasters end their broadcasts in the summer season with a warning to the listeners: "Don't forget to connect your antenna to the ground!". In Israel (in the Land of Israel) even the most attentive listener will not hear these things. why? Is there any negligence here on the part of the management of the radio station, or maybe it is completely unnecessary to defend against the danger of lightning by grounding as above?
How to defend against the danger?
The danger of lightning in Israel is much less than in most European countries, he replied that here it is an exceptional event. So far, not even one case of a lightning strike in the antenna has been known here. And even so, as a precaution, it is advisable to determine a sufficient shield (suitable protection measure) in the antenna, especially after (since) such a repair (installation - not repair of something broken) does not cost much, because a lightning strike could destroy the device and endanger the whole house and its inhabitants.
"Protects enough" how? A repair (repair) must be introduced that allows the antenna to be detached (disconnected) from the device and the company to "earth" directly. Through this grounding, a straight (direct) joint is made between the antenna and the water pipe, or groundwater (? not groundwater but to the ground using a grounding stake). For this purpose, a small switch is inserted inside the antenna (between the antenna and the antenna input on the radio) a small switch that is pulled by hand when needed or an automatic switch. It is possible that there was an arrangement that when the receiver was turned off, it would be activated An external relay that disconnected the antenna from the radio and connected it to the ground?) It should be noted that such a shield (protective means) is only useful for the antennas outside the house, and is completely unnecessary for the antennas inside. The use of the shield against the danger of lightning is necessary in Israel (the Land of Israel) also for another reason. During a strong dust storm, the antenna is charged with an electrical power of several thousand volts under the influence of sand grains flying in the air, and this causes unwanted blows to those who touch it, and in addition, sometimes damages to the device. With the above-mentioned shield, this danger can also be prevented.
Especially the owners of the "detectors" (a crystal radio was then called a radio detector; a detector is a detector, because its electronics include only a detector, without the amplifier tubes and without the need for a power source) and all devices that use headphones should be advised to use caution, because the direct connection between the device and The listener endangers the latter more than any other listener.
Some homeowners are afraid that the danger of lightning is multiplied (increased) by the antenna. These concerns are unfounded. On the contrary, the antenna may (may, is able; not the accepted meaning today which is of a negative interest) transfer the electricity in the air, which can be generated around the house, to the ground directly.
The transmitting lightning
How does the firecracker (lightning; do you know the phrase firecracker and thunder?) affect the reception? Is it appropriate and beneficial to hear the firecracker or should the device be turned off completely? A distinction must be made between the case where the firecracker is close to us or the case where the firecracker is very far from the place of reception. The danger of being struck by lightning is expected only for those who have an external antenna, then it is necessary to unplug (disconnect) the device. And what's more: the lightning strikes interfere with the reception, in such a way that it is almost impossible to receive (receive) broadcasts, and the same is true for the antennas hanging inside the house, although in this case there is no danger to the device itself. Where did the disturbances come from? Whoever believes that the sounds of lightning cause interference to reception is nothing but wrong. The voices do not affect it at all. (It is not the sound of thunder that causes the disturbances) It is an electrical voltage in the air that is several million volts that causes the disturbances, this electrical force erupts for fractions of a moment in the form of lightning and acts as a huge transmitter that causes a terrible chatter and in addition to that it does not transmit just one wave, like a normal transmitter, but all The waves are concentrated in it and transmitted (broadcast) at once. It is worth mentioning that Heinrich Hertz and Marconi used this virtue (property) of the electric spark as a transmitter in their first experiments. In these transmitters the waves were awakened not by lamps but by a large electric spark.
The disturbances that follow from a firecracker (lightning) are very intense and affect the reception, sometimes from a distance of hundreds of kilometers, and thus a firecracker (lightning) in Syria or in the West of the Jordan can disturb the reception on the island (Land of Israel) to a considerable extent. But if the firecracker is not near the local station, and the sounds are very weak and almost inaudible, then listening to the radio does not cause (causes, is a reason for) any danger and in general it is possible to receive the Jerusalem transmitter without interference, while the other transmitters are usually interrupted by loud rustling. Even in such a case, it is better to use short waves that have the virtue of lightning interference and do not affect them like the long and medium waves. (The intention is probably to recommend the reception of foreign stations on short waves, which are less disturbed by the lightning).
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It was unnecessary to translate words and sentences more than once. The article is beautiful though, and really takes you back in terms of language. Thanks!