Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [vintage]

For questions about early/old electrical technologies and devices that are no longer available today, or almost extinct.

For questions about early/old electrical technologies and devices that are no longer available today, or almost extinct.

This includes most kind of Thermoionic valves, gas filled tubes, magnetic tape cassettes and heads, Reel to Reel, CRT, Light pen, Light guns, Analog radios, VCR, Post office box, Telegraph, Electric heaters, Pipe light choke and starters, incandescent bulbs, Punch card readers, Landline telephone, rotary diallers, Meters of various kind based on Magnetic deflection, and every other kind of vintage electrical technologies.

162 questions
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Why were germanium diodes so fast and germanium transistors so slow?

Germanium diodes were used for Radar during WW2. Germanium transistors appeared about a decade later. Most early transistors were only specified for audio use, like the OC71. The specified RF types like the OC44 were only good for a few MHz. Why…
Autistic
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Are screened transistors an endangered species?

In the germanium transistor era, the RF transistors were PNP small signal devices. Some of these small metal cased BJTs had 4 leads instead of the usual 3. The metal can was isolated and the 4th lead was called the screen and was connected to an…
Autistic
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Sound pressure level in an electromagnet speaker compared to a permanent magnet speaker

Modern speakers have permanent magnets and are called PM speakers. Permanent magnet materials technology has improved a lot over the last 80 years. Around WW2, electromagnet (EM) speakers were common because permanent magnets were not as good as…
Autistic
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Can old vintage quartz crystals handle more power?

Old crystals are very large compared to present day devices. Vintage transmitter circuits did not have many valves in their line up. I have seen a 2 valve 50 watt CW transmitter for 80 meters in a 1950s electronics magazine. When transistors…
Autistic
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Help me identify this connector please!

this is the only connection on a vintage turntable I came across. what is it?
Ben Browning
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Positive Grid current in valves

Vacuum tubes are much more idiotproof than transistors. Grid current does flow during a significant part of the drive cycle in some classes of amplifier operation. Many high power tubes have really low grid current ratings. Why are the ratings so…
Autistic
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Russian germanium transistors

The germanium transistor era was long over in the west when the Berlin wall came down. Nowadays, new old stock Russian germanium transistors are appearing on world markets. Some musicians prefer germanium transistors due to their more gradual…
Autistic
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Volume control reliability

Log potentiometers were the mainstay for volume controls in radios .I have seen values of 5 to 10K in early solid state radios .Valve radios would use 250K to 1 meg .Crystal cartridge record players would use 1 to 3 meg.Sure these ballpark values…
Autistic
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