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Comment Re:I don't (Score 1) 385

And, as a result, the merchant will need to increase their prices to stay profitable.
In The Netherlands, most people I know don't have a credit card, but a debit card with chip and pin.
Guess how many fraudulent charges most of us get per year (or even in our lifetime): none!
Most people here act as if credit card fraud is a given, but only a minor nuisance.
They ignore that in the end they will bear the cost nevertheless, and that it is preventable.

Comment Slashdot leadership is stupid, or they cannot read (Score 1) 150

It still says
"Polls on the front page of Slashdot? Is the world coming to an end?! Nope; read more about it."
at the top of every story, one week after it had already become obviously clear that the Slashdot community unanimously judged polls on the front page to be a monumentally stupid idea.
Either Slashdot leadership do not read the page they urge us to read, or they are monumentally stupid themselves (or both, which I do not exclude)

Comment Re:For that matter... phones. (Score 1) 790

I dialed phone numbers by rapidly depressing the hook. Worked like a charm.
I then found out that 11 pulses followed by a few (2 or so) 'normal' digits would also give you a connection.
Judging by the response I got, I presume this was a number within the telephone company.
I was 10 years old at that time, so I hung up in a hurry ;-)

Comment Re:We Wish (Score 1) 663

If it would consume more energy to produce a solar panel than it will produce in its lifetime, then either:
- I would not be able to ever recoup my investment (but I can with current energy prices reach this in 15 years), or
- Solar panel producers pay far less for their energy than I do, or
- they would make a loss and go bankrupt.
The price of a solar panel will (except for subsidies) never be lower than the price of the energy needed to produce it.
As long as I can install one and make a profit, I don't believe that producing it will have cost more energy than it will ever produce.

Comment Re:Preach it (Score 1) 59

So if the ringer was ringing and you pick up the phone there might leak some of the 90 V signal into the microphone?

That wouldn't be too good for the microphone.
The switches of the hook are there to prevent that.
They connect/disconnect in such an order that the telephone exchange is signalled that you pick up the receiver so the ringer signal is switched off before the speaker and mic are connected. I once had a telephone where this dis not work properly. When you picked it up at the exact moment of a ring, a loud buzzing sound came out of the earpiece. Not nice.

And did you consider what happens if you put a High frequency signal onto the line? Some of the signal might be affected by the condensator combined with the mic, and a usable signal might gotten of it.

If the receiver is on hook, both mic and speaker are completely disconnected, as you can see.
The capacitor is in series with the ringer, not with mic/speaker.
Please let me know from the schematic (the one I linked to, or another one if mine is not correct for the phone you have in mind) what exact signal pathway you have in mind. "Some of the signal might be affected" is too vague to be refuted or confirmed.

Comment Re:Preach it (Score 1) 59

Yes, I know the difference.
I have disassembled T65 telephones, myself, and I did not find any difference to the schematic I linked to.
That is why I asked you to post the schematic of the telephones you disassembled that were different.
Unless you can do so, and explain how a telephone off hook can be used to eavesdrop on you, you confirm my opinion that you are a troll.
A moderately competent one, I must say: I'm still feeding you...

Comment Re:Yeah I remember that (Score 1) 64

Yeah, the display hardware of the ZX81 was brilliant in its simplicity.
Not only did it use the program counter as the character point er for the display, but the I/R (interrupt and DRAM refresh) register pair was used as a pointer into the character ROM. These were output automatically by the processor directly after the fetch of the instruction.
And each line of the display was ended by a HALT instruction, so short lines did not need the full 32 bytes.
And, and, and... I loved that machine for its (albeit just a _little_ bit convoluted) design!

Comment Re:Preach it (Score 2) 59

I'm guessing you never disassembled one to see how it actually worked. I did. Go ahead and find an exemplar and give it a go.

OK, here is the schematic of the most widely used mechanical telephone in The Netherlands: the T65.
When the telephone is on hook ("hoorn"), only the ringer (bel) is connected to the line.
I really cannot think of another arrangement: the ringer voltage is high (100V?) so you don't want that appearing over your mic or speaker.
Please share with us the schematic of the phones you disassembled, or are you really a troll?

Comment Re:Well I'm convinced it's true (Score 1) 216

Explaining it to the manufacturers of 900 kV stun guns will have no effect.
They know very well that their product does not reach 900 kV.
Those tasers may very well reach 90-100 kV (spark length of 3-3,5 cm), but not tenfold that.
It's just as with the 200W PMPO computer speaker sets that are supplied from a 12W transformer: pure marketing hype.

But, I agree with your main point: it is trivial to create a sufficiently high voltage in a small volume.
Even the simplest 2 kV fly swatter tennis rackets show that.

Comment Re:Well I'm convinced it's true (Score 4, Informative) 216

I built a stun gun capable of generating 900,000 volts on-demand out of a few dollars worth of parts and a 9 volt battery, and it fits in the palm of your hand

900V or 9 kV I would believe, 900 kV not so much.
You would need creeping distances of more than 300 mm just to prevent arcing and making the voltage collapse before it even reached the 900 kV.
"900 kV" and "fits into the palm of your hand" are mutually exclusive, I think.
(and yes, I've designed and built multi-kV devices myself)

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