The RUF combines the flexibility of a car with the high speed and zero emmissions of an electric train. It has wheels for the road and an combined rail and power connector in the middle of the car. The road travel is battery powered.
More - including prototype pictures - at www.ruf.dk
I would guess that the right place to put a capacitor is at the input of the speaker amplifier - so that the first stage in the amplifier does not receive any RF to rectify (and then amplify).
In the RC days, you had to select frequency by crystal selection.
The license free devices have similar ways to get their data sent - they do frequency hopping, direct sequence, etc. Please read the other replies about this.
The old RC gear at one frequency is just not a valid comparison to modern 2.4GHz devices.
The techincal explanation is about sum and difference frequencies generated by non-linear components.
Since you audio equipment is full of transistors and diodes (both of them non-linear) any incomming high frequency signal may be converted to a signal in the audio range. See my other comment about how to stop the problem.
Well, the basic thing to do is to prevent high frequency signals from entering you audio equipment.
How do the signals enter? By the wires. Wires with the right length function as antennas.
What can stop the signals? Anything with induction (coil) effects.
(Any amateur radio operator will know this, since they send signals with several 100 more power than any license-free device. Ask a HAM if you know one.)
Put a ferrite core around every wire leading to or from your audio equipment, as close to the enclosing as possible.
Look for ferrite cores in CB/walkie talkie shops or in HiFi-freak stores.
Could some one please explain? Are they sueing Yahoo! for some direct sales action (done by Yahoo!) or are they suing Yahoo! for linking to someone else who are selling the products in question?
A 16 year old Danish boy managed for some hours to control the trains on a major switchyard using only knowledge of the switching system and a stolen radio from the train operator.
He got caught when he by mistake changed the switches so that a high speed passenger train would be led onto the switchyard ! (The Automatic Train Control system set off the alarms)
The boy is in all respects an ordinary and clever boy with a huge interest for trains and how to operate them. In other words - he is by no means nuts.
Never the less he could have caused a disaster if the passenger train was so close that the ATC couldn't stop the train fast enough.
I suggest that you install two cables of unshielded twisted pair (UTP) type, CAT-5 standard or better from some central point in the house to every room in the house. And one television antenna cable. Finally one earthing cable.
Each UTP cable has 4 pairs of wires, 8 conductors in total.
You terminate each UTP cable in a RJ-45 female connector. The RJ-45 wall-mounted connectors are color coded, follow the codes carefully.
A main distributing frame with (a lot of) RJ-45 female connectors goes in the central location. You can use patch-cables on the main distributing frame to set up any kind of configuration you need, just by plugging in cables.
Each of the two RJ-45 connectors in each room will allow you to get anyting from doorbell or plain old telephone service (1 pair), ISDN telephones or 10 Mbit/s Ethernet (2 pairs), 100 Mbit/s Ethernet (4 pairs) into the rooms.
You can put a local telephone exchange and Ethernet hub in the central location. You can install an antenna signal amplifier/splitter in the central location.
I don't know the exact requirements for earthing of the main voltage in the States, but a good solution is to have a central earthing point (guess where!) and run one earthing conductor to each room. This will protect you computers since they will have the same potential level (voltages with respect to "ground").
All of this will be a physical star configuration, meaning that if any cable get cut by accident, only one room will be affected.
Good luck - I've installed the setup described above in my Danish 1898 house. You'll save quite a lot of hours by installing the cables during the construction instead of after:-)
Slashdot Mirror
Any country has an authority with the same goals as the FCC:
Set up limits for frequencies and radiation levels so that most people can use the air for communictions.
In my case, they are called "Telestyrelsen".
Torak - would you like that the strongest transmitter has the right to the air or is that just a bit too liberal?
Vote.
and again:
Vote.
Thank you I will. The info on interlingua.com is biased as well as esperanto.org so it will take some time to compair them.
interlingua is simply based on the most known words in the 3 largest languages of European origin.
Learn more here: www.interlingua.com or
www.interlingua.org
Drop Esperanto in favor of:
http://www.interlingua.com/
Drop Esperanto in favor of:
http://www.interlingua.com/
More - including prototype pictures - at www.ruf.dk
I never get the same IP number when I dial up the ISP. The said filter will not work with any dial up user, or am I missing a point here?
The EU-commissioner Mario Monti still wants an inquery on Microsoft.
Mr. Monti says that the US trial does not change his views. The US trial did focus on webbrowsers, the European trial will focus on servers.
The important question for the EU is that Microsoft Windows 2000 security software is designed only to work with Windows 2000 servers.
Do you mean "across the speaker terminals" ?
I would guess that the right place to put a capacitor is at the input of the speaker amplifier - so that the first stage in the amplifier does not receive any RF to rectify (and then amplify).
73 de oz1nkj
http://www.wirelessethernet.org/
'nuf said.
In the RC days, you had to select frequency by crystal selection.
The license free devices have similar ways to get their data sent - they do frequency hopping, direct sequence, etc. Please read the other replies about this.
The old RC gear at one frequency is just not a valid comparison to modern 2.4GHz devices.
The techincal explanation is about sum and difference frequencies generated by non-linear components.
Since you audio equipment is full of transistors and diodes (both of them non-linear) any incomming high frequency signal may be converted to a signal in the audio range. See my other comment about how to stop the problem.
What can be done?
Well, the basic thing to do is to prevent high frequency signals from entering you audio equipment.
How do the signals enter? By the wires. Wires with the right length function as antennas.
What can stop the signals? Anything with induction (coil) effects.
(Any amateur radio operator will know this, since they send signals with several 100 more power than any license-free device. Ask a HAM if you know one.)
Put a ferrite core around every wire leading to or from your audio equipment, as close to the enclosing as possible.
Look for ferrite cores in CB/walkie talkie shops or in HiFi-freak stores.
Some years ago it was 240 volts in the UK and 220 on the continental Europe.
A world-wide guide to plug and voltages around the world can be found here:
http://kropla.com/electric2.htm
Try http://www.dds.dk/ - it is the official homepage of the Danish Guide and Scout association. Only one page in English, though.
We monitor the stability, and our OS/2 box beats or matches several web hotels (NT, Linux, some other *nix'es), we monitor for comparison.
Still, we do think that our next OS will be Linux.
Yours in scouting,
Niels Kristian Jensen
They should not need to fight in order to continue giving away something.
If IRC collapses, chatters will have to go into the commercial "chat rooms" filled with adds, pop-up sh*t and such.
Tell the "hackers / crackers" you know about that very likely outcome of their activites.
A recent /. story told us about some site only allowing their IRC version - yes, it shows adds!
Best regards,
Niels Kr. Jensen
Not all the relays are blocked. Only the ones, AOL asked for!
Grandma will be able to send happy birthday 'cause she uses the valid mail relay(s).
Best regards,
NKJensen.
Did I miss it in the comments, or did no one mention the problem that arises if a copper circuit is hit by a lightning?
The hospital mentioned in the article could suddenly find itself without any network connection...
Could some one please explain? Are they sueing Yahoo! for some direct sales action (done by Yahoo!) or are they suing Yahoo! for linking to someone else who are selling the products in question?
Maybe OT but anyway:
A 16 year old Danish boy managed for some hours to control the trains on a major switchyard using only knowledge of the switching system and a stolen radio from the train operator.
He got caught when he by mistake changed the switches so that a high speed passenger train would be led onto the switchyard ! (The Automatic Train Control system set off the alarms)
The boy is in all respects an ordinary and clever boy with a huge interest for trains and how to operate them. In other words - he is by no means nuts.
Never the less he could have caused a disaster if the passenger train was so close that the ATC couldn't stop the train fast enough.
Security is alway an issue with humans!
A real time system meets deadlines - guaranteed.
With absolutely no missed ones.
REAL TIME does NOT mean fast. Known timing is the goal.
No Unix was written with that goal in mind, therefore the original post was right.
Please consider moderating the original post up!
Best regards,
Niels Krisian Jensen
Denmark.
P.S: Linux will still be a good platform for the larger part of most systems, which is not real time critical, e.g. HMI (Human-Machine Interface).
Ground loops is excacly what I was trying to warn against, thank you for the description.
I described how to create a star topology, which is free from ground loops by definition.
Pre-1996 houses in Denmark have no ground connector in the power outlets.
I suggest that you install two cables of unshielded twisted pair (UTP) type, CAT-5 standard or better from some central point in the house to every room in the house. And one television antenna cable. Finally one earthing cable.
:-)
Each UTP cable has 4 pairs of wires, 8 conductors in total.
You terminate each UTP cable in a RJ-45 female connector. The RJ-45 wall-mounted connectors are color coded, follow the codes carefully.
A main distributing frame with (a lot of) RJ-45 female connectors goes in the central location.
You can use patch-cables on the main distributing frame to set up any kind of configuration you need, just by plugging in cables.
Each of the two RJ-45 connectors in each room will allow you to get anyting from doorbell or plain old telephone service (1 pair), ISDN telephones or 10 Mbit/s Ethernet (2 pairs), 100 Mbit/s Ethernet (4 pairs) into the rooms.
You can put a local telephone exchange and Ethernet hub in the central location. You can install an antenna signal amplifier/splitter in the central location.
I don't know the exact requirements for earthing of the main voltage in the States, but a good solution is to have a central earthing point (guess where!) and run one earthing conductor to each room. This will protect you computers since they will have the same potential level (voltages with respect to "ground").
All of this will be a physical star configuration, meaning that if any cable get cut by accident, only one room will be affected.
Good luck - I've installed the setup described above in my Danish 1898 house. You'll save quite a lot of hours by installing the cables during the construction instead of after
Best regards,
Niels Kr. Jensen
I just want to support the previous poster. VM = Virtual Machine is prior art.