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Messages - syhprum

Pages: [1] 2 3 ... 139
1
Technology / Re: Thoughts on Wireless Electricity
« on: 06/03/2015 20:08:49 »
The problem with trying to harvest power from high voltage power line using a nearby antenna wire is the very high impedance of the source, the open circuit voltage of the received power is very high depending on the ratio of its capacitance to the power lines compared to its capacitance to ground but due to the low frequency the output impedance is very high making it impossible to harvest any useful amount of power 

2
Geek Speak / Re: HDMI cable weirdness - help me understand
« on: 05/03/2015 22:01:11 »
In a weak moment I connected the monitor on my computer with HDMI cable as the 8400GS video card that feeds the monitor has a HDMI connector, I was appalled how blurred the 1680/1050 pixel display was and quickly reverted the normal cable.

3
Technology / Re: Thoughts on Wireless Electricity
« on: 05/03/2015 21:49:23 »
Wireless electricity is useful for charging the batteries of electric bus's at bus stops and charging your cell phone without you having the bother of plugging it in, I don't think we will ever see the grand scheme of Nikola Telsa come to fruition

4
It would be a very foolish thing to accept a reward for betraying a mafia godfather I don't think you would live very long to enjoy it

5
I don't know how old this ex? mafia man is but I don't think they send you to jail in Italy if you are older than 70 and the wheels of justice grind very slow in Italy.
Any competent mafia godfather could make an offer he couldn't refuse to the registrar clerk and get his birth date altered.

6
Why not just email the makers of this cylinder they will have the answer, if you don't like the result try other makes and see how well their cylinders are insulated.
There is a minimum standard for insulation 2.5kW/24hr heat loss requirement of BS 5615 1985 you need only to work out how much electrical energy is required to replace the lost temperature .

7
Geek Speak / Re: Has anyone tried Windows 10?
« on: 15/02/2015 09:23:20 »
I find IE11 with windows 10 a continual source of annoyance with frequent stoppages needing page reloads, I hope when the genuine customer version is issued this will be dealt with meanwhile when I get fed up with it I revert to a TOR browser which is not so convenient to use but never drops out.

8
To transmogrify into a butterfly you must undergo a metamorphosis.

on a more serious note how do electrons survive floating in this negative charged eather

9
I don't have a printer port so I have to connect via an expensive USB adapter cable, you should have no problem with windows 7  windows will pull in a great range of drivers for antique printers if you are patient

10
If god made protons why did he not make it solid instead of a bag of Quarks, Gluons and what not, was it not as St Aquinas said because he was to busy creating hells for those who ask too many questions.

11
Geek Speak / How can I start my minidisk from software
« on: 12/02/2015 17:39:51 »
I record weather satellite pictures automatically on my minidisk recorder and with my new computer everything that is inputted to it is date stamped so when I wish to reproduce the pictures I have to reset the clock on my computer so that it thinks it is playing them at the correct time.
There is a program available (Wxtrack) that tracks the satellite and outputs a bleep at AOS and LOS that tells me when to start the play back from the recorder.
I would like to automate this is there any simple way I can get the computer to output a logic signal (thru the coms port ?) that would start recorder directly.
I am contemplating adding a tone detector to the recorder to generate this logic signal from the audio output of the computer but it would be more elegant if I could do directly.

12
No replies, few readers I thought it was a pretty thought provoking article and it was quoted on most of the science forums

13
Every year I visit friends in Indianapolis so that I can visit the Indy500 race , I find their irrational religious beliefs rather a strain but I have to remember not to argue or protests too much or I would have to pay for a hotel instead, I even attend church and have to work hard not to laugh

14
No

15
A new theory about the origin of the universe seems to give us back the ether sorely missed by we old timers

http://phys.org/news/2015-02-big-quantum-equation-universe.html?utm_source=nwletter&utm_medium=email&utm_content=splt-item&utm_campaign=daily-nwletter

16
Technology / Re: secure speech via telegraph cables
« on: 09/02/2015 11:35:31 »
Apparently the Idea had been around since 1928

"Computer Speech: Recognition, Compression, Synthesis

Speech compression, once an esoteric preoccupation of a few speech enthusiasts, has taken on a practical significance of singular proportion. As mentioned before. it all began in 1928 when  Homer Dudley, an engineer at  Bell Laboratories, had  a  brilliant  idea  for compressing  a speech signal  with  a bandwidth  of over 3000 Hz into  the  100 Hz  bandwidth  of a new  transatlantic telegraph cable. Instead  or sending the speech signal itself"

If they were prepared to employ 55 tons of equipment and 30kW a quite complex even a mini ENIAC like device could be built and not needing the one time pads a superior result


17
Technology / Re: secure speech via telegraph cables
« on: 09/02/2015 10:58:58 »
I was considered a dab hand with modems thirty years ago I remember that if you wanted to send pictures back and forth to the USA you had to add 73 to the dialled number to make sure you got a cable connection and not a satellite which was hopeless.
Dial up modems are little valued today but they incorporate some really clever electronics for less that 10.00   

18
Technology / Re: secure speech via telegraph cables
« on: 08/02/2015 22:03:31 »
For security the SIGSALY system used a frequency jumping system the one time pad key for which was stored in audio disks that had to be physically distributed before a conversation could take place and synchronised with the aid of the WWV standard frequency transmissions this would not have been needed if a cable had been used meaning the system would be quickly available.

19
Technology / Re: secure speech via telegraph cables
« on: 08/02/2015 21:23:50 »
Dial up modems can thru put 56Kb/s on a nominal 4kHz telephone line so 1500b/s is not so way out but as you say dispersion may be the problem, I don't think there would be any great problem doing it with modern electronics.
Modern Vocoders use far less than 1500b/s

20
WWII showed the need for secure voice communication between the UK and the USA to this end the 55 ton 30kW SIGSALY system was developed to scramble speech via a radio link.
Was a consideration given to using the telegraph cables between the UK and USA ? The better cables had a bandwidth of 100Hz and speech compressor's (Vocoders) had been developed in 1939 so it at first sight it would have seemed to be possible.

http://en.wikipedia.org/wiki/SIGSALY.

21
Technology / Re: Induction cooking & heat distribution
« on: 07/02/2015 21:54:22 »
I do not see any reason why 220v induction hobs should be higher powered than 110v ones, The power that devices can generate depends on the ratings the transistors that generate the high frequency current .
The electronics of these devices will consist of two units a chopper type PSU section that will take the incoming main AC and convert it to a DC supply suitable for the high frequency generating section and that section proper.
The amount of power consumed is relatively low and puts little strain on the mains supply.
American domestic mains supplies are normally  110v with one side grounded for light loads such as TVs lighting and such like or for heavier loads such as ovens or space heaters both 110v lines are used giving 220v to avoid feeding to much current into the grounded line.
We European's find this a little confusing as we are used to a 240v threephase system with three lines at 240v relative to ground.
 

22
It was not intended to be Eros that is just a colloquial name that it has acquired

23
I think we will have to learn to live higher CO2 and higher temperatures unless aliens invade and start to control us I cannot see any real progress being made as to the amount of CO2 we pump into the atmosphere

24
Technology / Re: Induction cooking & heat distribution
« on: 06/02/2015 08:01:13 »
Is the pan you are using specified for use with an induction hod?
I would expect a proper pan to be to use part iron and part aluminium construction
I do not think the supply voltage is relevant as presumably there is a chopper type PSU before the induction frequency generation.

25
It was reported that Hitler's doctors tried faecal transplants to cure his well document digestive problems, I don't know what they told him but they were very brave !

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