Questions tagged [history]
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39 questions
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Development of quartz resonator qualities over the decades
While writing this answer here, I had to admit I only have "…, I think"-level of knowledge what a 1970's quartz resonator for a consumer radio device would have been spec'ed at.
My ...
- 18.4k
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Postcard to a Ham Operator: Any clues here?
A friend of mine is trying to find anything that would provide a clue as to what his grandfather's Call Sign was. He forwarded this postcard to me. I don't see anything here that would be a clue, but ...
3
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1
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How did telegraph operators ensure they received the intended message? Was some sort of checksum used?
Assuming the operators were using Morse code (un-encrypted or otherwise) how could the receiver determine they got the correct message?
- 131
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What's the origin of "π-C" or "Drake modified pi" network for impedance matching / antenna tuner?
This is a history question.
This type of antenna tuner included the Drake MN-4, MN-4C, MN-7, MN-2000, MN-2700, Kenwood AT120, AT130, AT200, AT230, Yaesu FC-707, FC-757AT (Automated pi-C match), Tokyo ...
- 3,971
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"Shuttlecock" antenna
During the 1960s, it was common to see a radio aerial which looked rather like a shuttlecock clamped to the gutters of older houses. I estimate that the downward-pointing wires were of the order of 6&...
6
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2
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What is an undulator (as used for CW)?
There are historical references to a device called an "undulator" used for CW reception circa before and during WWII.
What is an Undulator (as used for CW recording)? How did they work (...
- 13.7k
4
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1
answer
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What was the first QSO by an astronaut? Was it code or voice?
Discussion under this answer to Could amateur radio operators or others contact the ISS against NASA's wishes? in Space Exploration SE explore some activity from the Mir and ISS stations and the Space ...
- 553
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Why do so many hams prominently display their callsign in the shack?
By ham standards, I'm far from being a long-time adept of amateur radio, but I've seen my fair share of shacks, both on the internet and in person.
What's always attracted my attention is that almost ...
- 469
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What band did walkie-talkies use in Europe before PMR446 was allocated?
The PMR446 band, now used for walkie talkies in Europe, was only allocated after 1997. I'm sure walkie talkies existed before that. What radio bands did those use?
- 415
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5
answers
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Why do operators mention the band when calling CQ on phone?
I'm a new-ish ham, licenced for about one year now.
Within that year I've heard a lot of CQ calls from other hams on phone (both HF and VHF), and it seems that a large portion of hams routinely ...
- 469
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Hardened UHF Antennas
Minuteman missile silos used an interesting hardened UHF antenna.
What kind of antenna is this? Does anyone have a drawing with a cross section?
Edit:
Jay Moore added a picture to a different type of ...
- 91
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2
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144
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Tuning two antennas using wire length
I've heard that in the early spark-gap wireless telegraphy era people would use kites with a wire acting as antennas and if the receiving side had a wire length that was an even division or multiple ...
- 47
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What do old unit abbreviations like "mfd" and "kc" mean, and where did they come from?
I saw a recent answer that mentioned "mfd" as a unit of capacitance, and I can recall having seen that term in old schematics and ham radio articles. I've also seen other non-SI unit ...
- 9,370
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How did SMA connector size become standard?
I'm working on a project in microfluidics and it has become apparent that a significant challenge to overcome is a lack of consensus in connector design.
I have been thinking about my time working ...
- 13
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What replaces the T/R switch in modern transceiver
I have been watching and reading about the time when receiver/transmitter were separated and T/R switches were used. Current transceivers are still sharing a single antenna to transmit and receive. ...
- 209