Silly Question. Bookshelf speaker and magnets.

Soldato
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Hi all

Sorry for sounding dumb, but hopefully this is an easy one. My PC is setup (just this moment) with WiFi6 and I have a PCIE adapter connected with an external antenna. The base of the antenna is magnetic. Quick pic below of where it is currently:

TPLink-Antenna.jpg


So as you can see it is just on my desk next to my 606 speakers. The cable has enough reach and I was going to place it on the top of the speaker. Is this a bad idea? Will I knack my speaker? :)

Thanks!
 
Man of Honour
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No, you'll be fine.

Speakers near old type tube TVs used to be a problem, but that's because the magnetic field from an unshielded speaker would divert the electron beam firing at the phosphor dot grid on the screen surface. It would cause colour staining and a partial magnetisation of the shadow mask.

The two magnets inside the B&W speaker will be more powerful than the base magnet of your Wi-Fi antenna. Put it another way, all Hi-Fi speakers would break if the proximity of the tweeter and mid/bass magnets were a problem to each other.
 
Caporegime
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I want to know why CRTs needed to made from concrete (at least that's what it felt like when moving them, especially flat screens). The buzzing from them always used to annoy me.

Haha no concrete, the electronics inside were just very heavy. Lots of glass, steel, and even a bit of lead. :)

Electron "guns", magnets, none of it was particularly delicate!
 
Man of Honour
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Most of the weight of the last generations of CRT TVs was in the glass.

Early cathode ray tubes were essentially a bulbous glass flask. The sphere is one of nature's stronger shapes because it will stand quite a lot of pressure as the shape is very good at spreading the loading forces whilst using minimal materials. The force comes from the partial vacuum that CRT require to work. Very old tellies based on the Braun CRT idea had the same kind of goldfish bowl bulge.

The drive for larger screens meant engineering a way to make the flask strong despite the increase in size. The answer was to increase the thickness of the front face of the tube. Tellies still had a bulbous screen, but gradually that got flatter as the manufacturing techniques improved.

A big change came with the introduction of the FST. The acronym stands for Flatter Squarer Tube rather than Flat Square Tube.

Sony had perhaps the best innovation. Their FST Trinitron screens had what was in effect a section of a large radius cylinder as the tube face. There was still a gentle curve from side to side, but top to bottom was straight. The catch though with all the FSTs was that the glass had to be really very thick, so they weighed a tonne.
 
Soldato
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Most of the weight of the last generations of CRT TVs was in the glass.

Early cathode ray tubes were essentially a bulbous glass flask. The sphere is one of nature's stronger shapes because it will stand quite a lot of pressure as the shape is very good at spreading the loading forces whilst using minimal materials. The force comes from the partial vacuum that CRT require to work. Very old tellies based on the Braun CRT idea had the same kind of goldfish bowl bulge.

The drive for larger screens meant engineering a way to make the flask strong despite the increase in size. The answer was to increase the thickness of the front face of the tube. Tellies still had a bulbous screen, but gradually that got flatter as the manufacturing techniques improved.

A big change came with the introduction of the FST. The acronym stands for Flatter Squarer Tube rather than Flat Square Tube.

Sony had perhaps the best innovation. Their FST Trinitron screens had what was in effect a section of a large radius cylinder as the tube face. There was still a gentle curve from side to side, but top to bottom was straight. The catch though with all the FSTs was that the glass had to be really very thick, so they weighed a tonne.
Imo the best change from crt to LCD was the weight then the reclaiming of large chunks of the room:p.
 
Man of Honour
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Imo the best change from crt to LCD was the weight then the reclaiming of large chunks of the room:p.
No argument there. :D:D:D

Though I still have a soft spot for it, IMO CRT had reached its practical limits as a domestic TV screen technology. Green issues aside, we'd also hit the buffers in terms of resolution; and geometry/convergence performance; and light output to name but a few issues. The Americans went down the road of HD-Ready CRT at 720p and 1080i resolution to go with the introduction of broadcast HD in the late 90s/early 2000s. Despite being much cheaper than early plasma, these HD CRT TVs were still very expensive and also limited in screen size. Convergence and geometry were always an issue.

One thing I do miss about CRT is the lack of 8-bit posterisation. It's also a digital signal phenomenon, so not entirely a benefit of analogue displays, but the way plasma and LCD shows colour bands in low colour-contrast graduated backgrounds even with an analogue source really ticks me off.
 
Caporegime
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I remember we used to have a 32" Bang & Olufsen Beovision, it weighed as much as a small planet, and carrying it was incredibly awkward because it was so front heavy due to the glass. In fact I think it had a sheet of flat glass in front of the slightly curved CRT glass as well!

Needed two people on the front and one on the back to move it.

Even the remote control could have been used as a murder weapon, it was made of a slab of metal. :p
 
Soldato
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I had a 32" Sony Trinitron in my first house - which had an upstairs lounge, with a staircase with 2 turns to get up to it. The guys who delivered the TV point blank refused to take it up the stairs - then asked me to sign a document saying they'd taken it to the lounge and installed it!

The size of the protective packaging meant that our hallway was blocked across its entire width until I managed to get it up the stairs too.
 
Soldato
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I had a 32" Sony Trinitron in my first house - which had an upstairs lounge, with a staircase with 2 turns to get up to it. The guys who delivered the TV point blank refused to take it up the stairs - then asked me to sign a document saying they'd taken it to the lounge and installed it!

The size of the protective packaging meant that our hallway was blocked across its entire width until I managed to get it up the stairs too.
I bet that took some doing:p.
 
Man of Honour
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In the late '80s I worked for a professional audio visual equipment supplier in W. Yorkshire. At the time the biggest tubed monitor we sold was the 27" Sony Pro-Feel. That was a hell of a thing on its own; a definite 2-man lift for a couple of strong lads. So when Mitsubishi announced they were doing a 33" or 37" tube monitor, well, that just dwarfed anything available at the time.

We got one in and stuck it in the showroom. It looked like someone had just parked the moon in there. It dwarfed anything else other than the Mitsi projector TVs we hired out.

A few days later, one of the senior sales guys announced he had sold one to the Bronte Parsonage visitor museum in Haworth, and we were roped in to help with the delivery.

If any of you ever visited the museum back then you might have gone to the cellar via a small winding stone staircase to watch the video film the museum had had made about the sisters and their lives. On the way down and back up - because there's only one route in and out - you'll have passed the knuckle skin four of us left on the walls getting this brute down stairs. We left there bleeding men. :D
 
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