Weird Light Switch - Any Ideas?

[cjard]

True that Non Contact Voltage testers must not be used to prove dead, but they still have a use. Also how is one supposed to ensure that a circuit or cable is truly dead before you get access to the potentially live terminations/conductors to allow you to prove dead. By definition you can't be 99% sure that a circuit is dead (And thus safe) until you make direct contact with a two probe tester or turn off the entire DB.

They are fine a first call for testing live/possibly dead PROVIDING that you follow with a proper 2 probe tester before commencing electrical work. (i.e Tracing the correct circuit to isolate in large commercial DB before testing again with a proper GS38 voltage tester.)

I'm not quite sure I understand the logic..

If you use one and it says it is dead, you get a proper tester out and test again to make sure.. it would be faster to use the proper tester initially?

You use one and it says it is live, you work with extra care or waste time tracing back how it can be live when you thought you'd turned it off, or you get a proper tester out and test again to make sure.. It would be faster to use the proper tester initially?

 

[cjard]

All digital data is sent, like a jigsaw, in chunks called packets.

Not all - There are plenty of examples of digital transmission which are not packet based.

True, but I think the actual point being alluded to before Internet Protocol was introduced just to confuse things, is that digital transmissions generally encountered in home use will have some form of error checking built in or a decoding step to analog that means a damaged digital stream doesn't work. This isn't like the old days where twiddling the aerial got you a picture with less noise.. Twiddling the aerial essentially either gets you a perfect picture or no picture

Ultimately, for the person with a 120 hdmi cable for the 2500 tv, if the 20 (hdmi cables of a useful length are seldom £2) cable from Asda works without picture artifacts, the £100 extra for the gold connectors and the ofc copper rolled on a virgin's thighs confers no advantage. The colour reproduction, quality of the bass etc, will be the same on both cables because the signal is digital.. It either arrives intact and decodable, or it doesn't.. The extra hundred quid might be justifiable in that it has Ethernet conductors, is 30metres long, is shielded etc but if it's a metre long and goes from bluray player under the tv, to the TV and the cable price is justified solely based on the price of the TV then I'd say it wasn't a wise purchase

 

[ban-all-sheds]

True that Non Contact Voltage testers must not be used to prove dead, but they still have a use. Also how is one supposed to ensure that a circuit or cable is truly dead before you get access to the potentially live terminations/conductors to allow you to prove dead. By definition you can't be 99% sure that a circuit is dead (And thus safe) until you make direct contact with a two probe tester or turn off the entire DB.

Please consider that the context here is not a large commercial DB, it's a domestic dwelling with a "99% chance" that there's one visible CU for the whole installation.

 

[ban-all-sheds]

Some of the digital audio broadcasts in the U.K. don't come anywhere near the quality of good stereo multiplex FM,

You man that some do?

some of them really cover the screen in logos and badges, some like viva you can expect to see 3+ frequently.
in fact, I watch little to no TV.

I don't watch any with DOGs. Come that day all channels have them comes the day I stop altogether.

 

[Cinobite]

Ultimately, for the person with a 120 hdmi cable for the 2500 tv, if the 20 (hdmi cables of a useful length are seldom £2) cable from Asda works without picture artifacts, the £100 extra for the gold connectors and the ofc copper rolled on a virgin's thighs confers no advantage. The colour reproduction, quality of the bass etc, will be the same on both cables because the signal is digital..

Absolutely not. Despite the support for different versions of the spec, you have support for different features like HDCP, 3D, XVYCC, colour depths, bit rates, bandwidths - some HDMI cables don't carry sound. Add on top purer raw materials with more sheilding and you will get a better picture.
Sure it might "work", that doesn't mean it's good. You wouldn't put £20 tyres on an Aston Martin Vanquish.
If you're happy with the reproduction shoddy cables, freeview and MP3 give you (and to that end these ridiculous illegal movie stream apps everyone thinks are so amazing at 272 lines) - then you really don't need or should be paying for high quality AV kit

 

[ban-all-sheds]

What does the quality of an HDMI cable have to do with whether the devices it connects implement High-bandwidth Digital Content Protection? Or whether the devices do 3D? Or extended gamuts? Or more bits for colour? Or can support audio over HDMI (surely you aren't trying to claim that some HDMI compliant cables somehow lose the audio information embedded in the signal?)

As for the £20 tyres for an AM - nobody makes cheap tyres in that size, but if they did, and if they were genuinely safe, then why not?

The fact that you think that's a good analogy speaks volumes for your ability to understand what you're talking about.

But hey - if you like the smell of warm snake oil when watching TV, go for it.

 

[Cinobite]

Because the cable spec needs to support such features that's why. If the cable doesn't have the pins or bandwidth to carry a 3D signal, it doesn't matter how amazing the 3D TV is, it's not going to work - come on, this is basic physics.

£20 tyres - because, safe or not, they are lower quality, don't perform as well and wear quicker. To be quite frank, the fact that you even questioned that speaks volumes for YOUR ability to understand things. - May I ask what car you own?
You're clearly the type who just buys the cheapest of everything and doesn't believe that quality of components makes a difference, so I guess we'll leave it there.

 

[bernardgreen]

It is also basic physics that electricity propagates along gold at a slightly different speed than it does through copper. So gold plated copper wire will distort a digital pulse more than plain copper wire would ( or plain solid gold wire would ). Put a pulse into the end of the cable, some goes through the gold and arrives slightly before ( or is it later ) than the rest of the pulse that went via the copper.

 

[winston1]

Because the cable spec needs to support such features that's why. If the cable doesn't have the pins or bandwidth to carry a 3D signal, it doesn't matter how amazing the 3D TV is, it's not going to work - come on, this is basic physics.

£20 tyres - because, safe or not, they are lower quality, don't perform as well and wear quicker. To be quite frank, the fact that you even questioned that speaks volumes for YOUR ability to understand things. - May I ask what car you own?
You're clearly the type who just buys the cheapest of everything and doesn't believe that quality of components makes a difference, so I guess we'll leave it there.

There are no extra pins required to carry 3D. I use a 99p HDMI cable for 3D and it works as well as any other.

 

[ban-all-sheds]

Because the cable spec needs to support such features that's why. If the cable doesn't have the pins or bandwidth to carry a 3D signal, it doesn't matter how amazing the 3D TV is, it's not going to work - come on, this is basic physics.

It's also basic physics that a cheap cable with the right number of pins has the same number of pins as an expensive cable with the right number of pins.

It's also basic physics that a cheap cable with enough bandwidth to carry a given amount of information has enough bandwidth to carry a given amount of information.

Rather than ask you to revisit the question, I'll ask you to provide evidence of properly conducted, independently verified, double-blind testing which supports your position. Feel free to confirm that there is none by either admitting that, or by having another failed attempt at bluster, or by simply ignoring that request.

£20 tyres - because, safe or not, they are lower quality,

By what objective, evidence-based, scientific/engineering criteria?

don't perform as well

By what objective, evidence-based, scientific/engineering criteria?

and wear quicker.

That's a purely financial consideration. If a £200 tyre does not last at least 10x as long as a £20 one then from the POV of wear the cheaper one is superior.

To be quite frank, the fact that you even questioned that speaks volumes for YOUR ability to understand things.

You wouldn't know.

May I ask what car you own?

What's the relevance of that?

You're clearly the type who just buys the cheapest of everything and doesn't believe that quality of components makes a difference, so I guess we'll leave it there.

I'm the type that believes in real proof. You clearly are not.

I'm the type that believes in scientific and engineering rigour. You clearly are not.

I'm not a gullible idiot. So I guess we'll leave it there.

 

[cjard]

£20 tyres on a vanquish is an analogue argument, not a digital one. We can turn it digital If we assume that the owner has no tyres, will only ever drive in the dry and at 30mph and has just £20 in his back pocket then they make perfect sense because they meet the spec for the job. They also cost £20 and will perform no differently than £2000 ones

If you then say he wants to track day the car, then they are no longer adequate, the car will crash and be destroyed.

The point is that if you can buy a 20 quid hdmi cable for your TV that works and enables all the features of your 120 quid one, then 100 quid was wasted, because in the digital world, it either works perfectly or it doesn't.. Theis no halfway house, you don't have one cable reproducing richer colours or deeper bass and clearer midrange when it carries a digital signal, no matter how many virgins thighs it's been rolled on to justify the extra hundred quid

You have to go a little further than "I bought a 120 quid cable for the main tv because the main tv was 2500 quid, but a 5 quid cable for the 100 quid tv" because unless some salesman said "you should spend around 5% of the TV price on cables" and you were taken in by it, your spending method has no scientific base

 

[Cinobite]

it either works perfectly or it doesn't.

This is simply not true as evident by anyone who has seen digital breakup on a freeview or DAB broadcast

 

[bernardgreen]

This is simply not true as evident by anyone who has seen digital breakup on a freeview or DAB broadcast

Most ofthat is due to interference on the digital signal received at the aerial. There is a vintage car with un-supressed ignition that passes here occasionally and that breaks the sync causing the picture to freeze or pixilate.

In the day of analogue when un-supressed cars or motor bikes passed there were some short lived blips on the sound and black or white specks on the screen but the picture and sound were not interrupted.

 

[stillp]

In the day of analogue when un-supressed cars or motor bikes passed there were some short lived blips on the sound and black or white specks on the screen but the picture and sound were not interrupted.

Not where I lived Bernard - picture and sound were both lost in white noise for several seconds.

 

[ban-all-sheds]

This is simply not true as evident by anyone who has seen digital breakup on a freeview or DAB broadcast

No - that is something which is believed to be evident by someone who understands so little about what is going on that he doesn't realise that what he's seeing is a mix of working perfectly and not working at all.