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Here's one for the books

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(@paden-cash)
Posts: 11088
Topic starter
 

I don't guess anybody nowadays that designs wireless networks knows about vacuum-tube generated superheterodyne signals.

https://www.bbc.com/news/uk-wales-54239180

Makes me want to drag that old Zenith out of the garage to see it 'works' in my neighborhood.?ÿ 😉

 
Posted : September 22, 2020 10:09 am
(@andy-j)
Posts: 3121
 

I wish they went into more detail on how that happened.?ÿ

 
Posted : September 22, 2020 10:18 am
(@dougie)
Posts: 7889
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Posted : September 22, 2020 12:49 pm
(@paden-cash)
Posts: 11088
Topic starter
 

Me too.?ÿ I'm just surprised it doesn't happen more often.

I'm not much of a brain on such matters but from what I've been able to read it's probably a 'dirty' RF (radio frequency) signal generated by notoriously poor component shielding in cheap TVs (and other equipment like microwaves).?ÿ

Now when TV was invented I din't think anybody thought we would all be connected with say a 2.4 GHz signal running only hundredths of a watt.?ÿ A power supply for and old TV is probably generating 50 to 300 watts or more.?ÿ Any old or malfunctioning component can probably?ÿ generate plenty of RF noise with harmonics all over the frequency spectrum with plenty of power to walk all over weaker signals.

 
Posted : September 22, 2020 1:05 pm
(@jules-j)
Posts: 727
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When I was a young lad, my buddy's father was a hvac master tech on commercial buildings. This was the early 60's. He came home on day with a 3 foot tall vacuum tube and transformer he took off a neon sign. My buddy decided we were going to build a radio with it. We got books on the subject and got circuit boards and other tubes. We got it all put together, and ran a wire for the antenna. We cranked that baby up. All the tubes were glowing and humming. We had a dial trying to tune in a channel when we got a knock on the garage door. Holy crap! It was the FCC in a van with a round antenna on top of it. The FCC guy said, where's it at? Never mind he heard it and then put his eyes on it. He unplugged it and another guy from the van came and helped him load our stuff in the van. He said we shut down a 1/2 mile of communications. Police Radios, tv, the works. He said if we didn't mind he was going to keep our radio and call it even. We watched them drive off with our jammer. I don't remember us saying a word.?ÿ

 
Posted : September 22, 2020 1:41 pm
(@a-harris)
Posts: 8761
 

Somebody would be buying me a new bigscreen, no matter what my old one was jamming.

They got to upgrade and allow the old stuff to work too.

If not, I'd be jamming them on and off as long as that old system would power up.

 
Posted : September 22, 2020 3:01 pm
(@bill93)
Posts: 9834
 
Posted by: @a-harris

I'm sure the problem wasn't an old design, but rather that something in it was failing and causing the spurious emissions.

 
Posted : September 22, 2020 3:41 pm