[OT] -- Oh Joy! I'm Connected again!

The statists and other war addicts hate it because it makes you peaceful. :-)

Cheers! Rich

I am not exactly sure how it works, but you might try setting the idle time to 0 to keep somobody from jumping in while you are not sending/receiving. Also, somebody mentioned directional antennas. One on the router end should work if you are always in the same direction from it. MFJ Enterprises sells one for $29, but they can be had for a lot less. MFJ claims 15 db gain.

Tam

Ecnerwal wrote: (snip)

As with surge surpressors you need a good ground on both ends. That is, the appropriate ground for the building.

I once wondered about a box on one end, plastic with appropriately isolated power and a short optical link. Maybe with power for the remote side coming through the conduit. Done right, you should be able to get a foot or so of isolation between the two sides.

-- glen

Wow. A pneumatic transport system for fat rats. :-)

Ciao,

Peter K.

--
"And he sees the vision splendid 
of the sunlit plains extended
And at night the wondrous glory of the everlasting stars."

Four examples of moisture resistant Cat5 cables:

Lightning may use a first building as a lightning rod to find earth ground, destructively, via electronics in the second building. This problem and the simple, inexpensive solution that was standard even

100 years ago was discussed in "Long cat5 run question" in alt.internet.wireless on 24 Jan 2008 at:

So many 'computer experts' have so little understanding of electricity as to not understand why phone companies did this routinely for 100 years - without wireless. They are recommending only what they understand.

This same mindset assumes damage from lightning cannot be avoided. Worse is the myth that a sacrificial switch will protect equipment. How do surges do damage? First current is flowing in everything in a path from cloud to earth ground. Everything including that switch. Long after, some item or items in that path fail. So what did the 'sacrificial switch' do? Just added to the list of damaged items. Damage? Even properly selected and installed protectors remain functional after every lightning strike.

Nothing stops surges (except in myths). Surges are routinely made irrelevant when diverted to earth before entering a building as made obvious in that Electrical Engineering Times article discussed in "Long cat5 run question". This earthing requirement defines where that Cat5 wire enters each building.

I'd go with a 3/4" or 1" conduit between the buildings for the cable or fiber, and tie the ground bonds together between detached garage and house with an external link.

They do make inexpensive media converters, so you can run cheap pre-terminated fiber between garage and house, and turn it back into CAT-5 when you get there. (They make 100' "patch cords".) If the buildings have totally separate power sources you really should do it this way, so you don't chance ground loops.

And run the garage media converter from the garage power that is also running the garage computer - taking a power lead from the house just defeated the whole idea of ground-loop isolation...

Water in the conduit isn't that big a deal, most "Riser" rated cable sheath will resist some damp. And it's cheap enough you can replace it if it goes bad in 5 years. If you really want to only do it once they do make filled CAT-5 cable, with a conduit you don't need the full direct burial armored cable.

-->--

Connecting grounds between two structures with a buried ground conductor is also recommended. But the critical factor - what telcos everywhere routinely do so that 100 surges from every thunderstorm cause no damage - is to connect every incoming wire in every cable to earth ground where all cables enter a building. Ethernet wires cannot be connected directly to ground and still provide ethernet service. So a protector makes that earth connection. A connection from each wire, 'less than 10 feet', to the structure's common earthing electrode.

This application note demonstrates the concept:

Two structures are a building and an antenna tower. Each has a single point earth ground. Any wire that enters that structure first connects to that structure's earth ground. Even underground wires must be earthed - as demonstrated in the application note.

To make a system even better, a buried conductor interconnects each building's single point earth ground.

These simple and so inexpensive solutions make wireless and fiber optic unnecessary. After all, same solution has been standard in telco facilities for over 100 years virtually everywhere in the world.

Some protector examples that can make that 'less than 10 foot' connection from each wire to earth ground are:

Each protector's most critical connection is to earth ground. As demonstrated by formulas in both front page Electrical Engineering Times articles, distance to earth ground is important. That ground wire connected to a wall receptacle safety ground is not sufficient for earthing - too far away, too many sharp bends, too many spliced, etc. An effective protector connects short to a building's single point earth ground so that surges need not enter that building:

Cable TV does same. That wire also drops down to make an essential (and short) earthing connection before rising back up to enter that building. Just another example of what is demonstrated in that erico.com application note and what an ethernet protector also does.

Solution is so inexpensive, so simple, and found virtually everywhere when damage is not an option. A connection between building earthing electrodes only makes protectors even more effective so that surges do not seek earth ground, destructively, via ethernet ports.

Excellent information on surges and surge protection is in an IEEE guide at:

And one from the NIST at:

The IEEE guide is more technical (and useful).

An entry protector is a good idea.

You want a *short* connection from the entrance protectors (cable, phone, ethernet) to the earthing wire at the power service, not the earthing electrode. For a surge, the inductance of a wire is more important than the resistance because a surge is a short event. You can get high voltages with surge currents on relatively short lengths of wire. With a strong surge the ground reference at a building will rise thousands of volts above ?absolute ground?. You want the power and signal wires to rise together. The author of the NIST guide has written "the impedance of the grounding system to `true earth' is far less important than the integrity of the bonding of the various parts of the grounding system."

The IEEE guide explains that plug-in suppressors work by clamping the voltage of all wires (power and signal) to the common ground at the suppressor. Plug-in suppressors do not work primarily by earthing. (IEEE guide starting pdf page 40.) Both guides say plug-in suppressors are effective.

Note that all interconnected equipment needs to be connected to the same plug-in suppressor, or interconnecting wires need to go through the suppressor. External connections, like phone, also need to go through the suppressor. Connecting all wiring through the suppressor prevents damaging voltages between power and signal wires. These multiport suppressors are described in both guides.

The IEEE guide says ?there is no requirement to limit the voltage developed between the core and the sheath. .... The only voltage limit is the breakdown of the F connectors, typically ~2?4 kV.? And "there is obviously the possibility of damage to TV tuners and cable modems from the very high voltages that can be developed, especially from nearby lightning." A cable entry ground block does not provide complete protection.

--
bud--

Ah, you young pups. Have no clue what communication is. When I was a kid, we had paper cups and a string to run from the house to the garage.

-- Christopher A. Young Learn more about Jesus

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Use conduit (PVC, and use primer and cement on the joints) - it's cheap, and you only have to dig the hole once. When 100 gigabit horsehair becomes the next big thing in networking, pull out whatever is in there, and pull in 100 gigabit horsehair - or 5 terabit spider silk, or whatever the next thing is.

You must be too young fto remember speaking tubes. There were no paper cups back then.

Jerry

--
Engineering is the art of making what you want from things you can get.
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Paper cups are just a modern cost reduction ruse, with a severe lifetime penalty. We used a clay pot and cat gut.

Regards, Steve

My buddy next door and I had tin cans full of rocks at each end that we used to "ring" our string telephone by tugging on the string. We thought that was quite advanced! The best talking cups were the round Quaker Oats boxes.

Don Young

I definitely agree. Fiber converters are not expensive, last long, eliminate lightning problems, there are 50 year life direct burial cables available, and if you can obey an about 2 foot minimum bending radius, work great.

Like this :)

Cheers, Martin

--
martin.j.thompson@trw.com 
TRW Conekt - Consultancy in Engineering, Knowledge and Technology
http://www.conekt.net/electronics.html

Actually, I do fto remember speaking tubes. You'd blow into it, and it would whistle at the other end. Until the other person pushed the little handle.

-- Christopher A. Young Learn more about Jesus

.

You must be too young fto remember speaking tubes. There were no paper cups back then.

Jerry

-- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Oohhh... a greenie? Back to the Earth? Wore leather shoes, and denim jeans, too?

-- Christopher A. Young Learn more about Jesus

.

Paper cups are just a modern cost reduction ruse, with a severe lifetime penalty. We used a clay pot and cat gut.

Regards, Steve