3 ms·

This is not entirely correct, Raytheon were going for a slightly higher frequency (2.6 IIRC) and the FCC ordered them down (forcing the recall of their trial ov

This is not entirely correct, Raytheon were going for a slightly higher frequency (2.6 IIRC) and the FCC ordered them down (forcing the recall of their trial ovens) because GE wanted to use crystal oscillators (klystrons) in the 1.2GHz range, and they wouldn't need to worry about the awful klystrons harmonics if they could bleed into 2.4. GE moved to magnetrons shortly afterwards anyway, I expect they hadn't had the radar manufacturing scale that Raytheon did at the end of the war.

surprisetalk 2y ago
Thanks for the fact-check! Just added this clarification to the article. Should be live in a few minutes
- anotherhue 2y ago
  Nice. I'd also suggest moving the spencer patent further down since it came several years later then the frequency allocation. Check my early early HN submissions for more info. Edit https://www.indiegogo.com/projects/why-2-4ghz-chasing-wireless-history#/updates/all https://www.indiegogo.com/projects/why-2-4ghz-chasing-wirele...
- JKCalhoun 2y ago
  Anything to the story (urban legend?) I grew up hearing about the origin of the microwave oven being from sailors witnessing sea birds being cooked by the radar dishes on their ships?
  - hyperdimension 2y ago
    Funny. The story I was told was a soldier's chocolate bar melted in his pocket when next to a radar antenna. Who knows, maybe it was neither.
    - richk449 2y ago
      It’s a well documented story: https://www.technologyreview.com/1999/01/01/236818/melted-chocolate-to-microwave/ https://www.technologyreview.com/1999/01/01/236818/melted-ch... It was Percy Spencer - fourth employee at Raytheon (third employee was Vannevar Bush, for reference)
HankB99 2y ago
(thread drift) Decades ago I did a job for Raytheon (S/W for an X-ray machine control.) The Raytheon guy that hired us talked about standing in front of one of those huge radar horns to warm up as a young serviceman. I didn't RTFA but I wonder if the history went back that far.
- anotherhue 2y ago
  I read many similar instances when I was doing the historical research into this. It's true of any high power radio system. They did some truly horrendous studies on rabbits.
  - sidewndr46 2y ago
    Not at all. If you stand near a large higher power antenna below 2.0 MHz or so you can't measure any heating at all.
    - anotherhue 2y ago
      Fair enough, I haven't had much sub-VHF experience. Thank you.

surprisetalk 2y ago

Thanks for the fact-check! Just added this clarification to the article. Should be live in a few minutes

anotherhue 2y ago
Nice. I'd also suggest moving the spencer patent further down since it came several years later then the frequency allocation. Check my early early HN submissions for more info. Edit https://www.indiegogo.com/projects/why-2-4ghz-chasing-wireless-history#/updates/all https://www.indiegogo.com/projects/why-2-4ghz-chasing-wirele...
JKCalhoun 2y ago
Anything to the story (urban legend?) I grew up hearing about the origin of the microwave oven being from sailors witnessing sea birds being cooked by the radar dishes on their ships?
- hyperdimension 2y ago
  Funny. The story I was told was a soldier's chocolate bar melted in his pocket when next to a radar antenna. Who knows, maybe it was neither.
  - richk449 2y ago
    It’s a well documented story: https://www.technologyreview.com/1999/01/01/236818/melted-chocolate-to-microwave/ https://www.technologyreview.com/1999/01/01/236818/melted-ch... It was Percy Spencer - fourth employee at Raytheon (third employee was Vannevar Bush, for reference)

HankB99 2y ago

(thread drift) Decades ago I did a job for Raytheon (S/W for an X-ray machine control.) The Raytheon guy that hired us talked about standing in front of one of those huge radar horns to warm up as a young serviceman. I didn't RTFA but I wonder if the history went back that far.

anotherhue 2y ago
I read many similar instances when I was doing the historical research into this. It's true of any high power radio system. They did some truly horrendous studies on rabbits.
- sidewndr46 2y ago
  Not at all. If you stand near a large higher power antenna below 2.0 MHz or so you can't measure any heating at all.
  - anotherhue 2y ago
    Fair enough, I haven't had much sub-VHF experience. Thank you.