Phones, Electronics & Radios

Dynamic microphone MD-42 produced of Tula factory "Octava". The microphone is in exellent working condition, tested with ohmmeter. Unlike the previous model MD-41, this microphone has a decorative round grille made not of painted aluminum but of chrome-plated steel. This instance has been repainted. On the front grille there are such inscriptions and symbols: the name of the microphone, the state standard number, the Oktava factory mark and the year of manufacture - 1958. Technical specifications: Directional characteristic - circle Type non-directional Nominal frequency range 100-5000 Hz The unevenness frequency response 12 dB Output resistance 250 ohms Axial sensitivity level -72 dB Normal sensitivity level 1.25 mV Height 3.7" / 95 mm Weight 1.2 lb / 0.56 kg

Old Soviet desktop telephone. Manufactured in 1968. An interesting model that has a microphone, perhaps so that two people can talk at the same time. At the back there is a socket for two wires, possibly for connecting headphones, so that the second person who will use the microphone can listen to the interlocutor. There are three not very noticeable defects, two of which are on the back side (see photo 8). At the site of the defect in the front part, if you wish, you can try installing a socket for a 3.5 Jack type plug and connecting headphones through it for a second subscriber, who will speak through the microphone or a speaker for speakerphone. On the front there is a peephole with an indicator, and behind it there is a lamp inside the case, which apparently should glow or blink when the phone rings. The operability is unknown, but no damage is visible inside, all parts are intact.. In the case of if it is will be used for its intended purpose, as an alternative a modern electronic filling can be installed inside the case, for example, from the walkie or Arduino GSM module for use with modern SIM cards. And of course, it can be used simply as a decoration for the interior.

Soviet knife switch in good working condition, designed for 24V and 5A. Produced at the Moscow FEP plant - (PhysElectroPribor), short for "Physical-Electrical Devices Factory", began its work in Moscow in 1933, seems to be working now. Size (by base) 6.2x2.3" / 159x59 mm

Old knife switch, in working condition. Judging by the presence of a jagged gap in the contacts, its original purpose was to turn off the old radio antenna during a thunderstorm. Therefore, this is not a simple switches, but the so-called lightning rods, as it is said in the 1959 book "Young Radio Amateur" in photo 7. It also shows a diagram of its connection between the antenna and the radio receiver. It was apparently once coated with chrome, which has partially peeled off. Such knife switches were used until the early 1960s to work with detector radios, which later fell into disuse. But of course, such switches can also be used for their usual purpose to open electrical circuit. Manufactured at the Moscow factory ATE-1, which was founded in 1929 and produced equipment for the automotive and aviation industries. https://ate-1.ru/history/ Length 4.7" / 120 mm

Rare large and heavy old Soviet microphone, in good working condition, tested with ohmmeter. The upper part can be tilted on the hinge. Made in 1956. The upper part is made of aluminum, the base is cast from cast iron, which is why the weight is so large. Microphones of the SDM series produced in the Stalin era from the late 40s to 50s at the Odessa factory "Red October". As can be seen from the number S/N 3654, the edition was small. The name SDM apparently means a studio dynamic microphone. The steel connector can be inserted into the microphone in two positions, possible for some two operating modes (when checking there was resistance in both positions). Technical data: Nominal frequency range: 60-8000 Hz Frequency response flatness: 12 dB Nominal load resistance: 200/600 Ohm Standard on-axis sensitivity level: -72 dB Sensitivity at frequency 1000 Hz at rated active load: mb⋅n-¹⋅m² 1.1/2 Directional characteristic type: Omnidirectional circular Height 7.28" / 185 mm Diameter of base 4.7" / 120 mm Diameter of the upper part 3.1" / 79 mm Weight 6 lb / 2.72 kg

Set from telegraph key, two buzzers for audible operation indication and connecting wire, in excellent condition, in original packaging Both buzzers are in working condition, when connected to keys and power sources, they should emit short or long beeps to the beat of pressing a key. Checking the operation of these buzzers can be seen in this video (test voltage 5.2 V): https://youtu.be/Kbi_8Fz_F4I Once upon a time in this set there were two identical keys, only this one left, but for its intended use it is not at all necessary to have a second exactly the same key, you can use any other Morse key that has at least two contacts for connecting wires. On telegraph key are shown on top Russian letters and their corresponding Morse code values. Manufactured at the 2nd Kharkov experimental plant "Promsvyaz" (Industrial communication). Size of key by base 4.3x2.7" / 110x70 mm