C wrote:

On Tue, May 6, 2014 at 9:06 AM, Per Jessen wrote:

...

mk-lists@email.de wrote:

...

I am wondering whether KTp is actually already an alternative to Skype these days…

Any VoIP solution is an alternative, it's only a matter of who you want to talk to :-(

That is a real "gotcha". If the majority of your contacts are using Skype (on Windows/OSX/Android)... you're a bit stuck.

Yep, that's what I meant. It's a pity that Skype only works with Skype, imagine what that would have done to early telephony if you'd needed matching telephone devices.

One alternative client that some people (in my circles at least) are starting to use is Viber.

I've seen that mentioned, but AFAIK it's only yet-another-voip solution. For the mobile it's seems downright silly, but maybe given the right kind of subscription ? -- Per Jessen, Zürich (15.2°C) http://www.hostsuisse.com/ - virtual servers, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

C wrote:

On Tue, May 6, 2014 at 9:51 AM, Per Jessen wrote:

...

C wrote:

...

On Tue, May 6, 2014 at 9:06 AM, Per Jessen wrote:

...

mk-lists@email.de wrote:

...

I am wondering whether KTp is actually already an alternative to Skype these days…

Any VoIP solution is an alternative, it's only a matter of who you want to talk to :-(

That is a real "gotcha". If the majority of your contacts are using Skype (on Windows/OSX/Android)... you're a bit stuck.

Yep, that's what I meant. It's a pity that Skype only works with Skype, imagine what that would have done to early telephony if you'd needed matching telephone devices.

Well... in a way you did need matching devices in the earliest systems..

Yeah, I knew someone would want to point that out :-)

and even into our generation.

If we exclude the proprietary technologies (Skype, Viber), where do we need matching telephony devices/networks?

Some early phones were purely acoustic for example.

wire-and-tin-cans ?

Other phones were "party-line" systems that only worked with other "party-line" phones. Electricity was like that too, and there were proprietary systems that directly competed with each other on DC and AC transmission. Televisions went through a similar period (in the infancy) with mechanical vs electronic televisions. Even now, you have competing tech that requires matching devices (NTSC, PAL SECAM).

Ah no - not matching devices, only matching technology. The significant difference (when compared to the Skype situation) being that anyone is free to develop devices using either technology.

For the Linux desktop, it's a mix of Skype, Viber, Ekiga, and lately I've started tinkering with Telepathy. I'd prefer to roll it all into one client that allows me to connect to SIP, Skype and Viber... but... so far no luck.

Yeah, if only SIP was as popular as Skype. -- Per Jessen, Zürich (18.1°C) http://www.dns24.ch/ - free dynamic DNS, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2014-05-06 12:25, Per Jessen wrote:

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Well... in a way you did need matching devices in the earliest systems..

Yeah, I knew someone would want to point that out :-)

I was going to, just he got there faster :-) In my country, there were at the start about one phone company per city, or even more. Some interconnected, some not. The hardware was up to them, basically the Graham Bell phone. Later, they were all mandatorily absorbed into a state owned/controlled monopoly, I'm not sure if a General Electric subsidiary or AT&T. Compatibility was ensured because it was a monopoly, and then many countries did about the same thing. And then there were international agreements - but you only have to look at the configuration of a plain modem device to find out that each country defined their own parameters such as ring tone, duration, etc. And there are dozens of tones and parameters, all different. I think that only the voltage is the same everywhere: 48 volts. For an obvious reason: it was 4 car batteries in series. With positive ground (to avoid corrosion IIRC).

...

Some early phones were purely acoustic for example.

wire-and-tin-cans ?

Air voice pipes in ships...

...

Other phones were "party-line" systems that only worked with other "party-line" phones. Electricity was like that too, and there were proprietary systems that directly competed with each other on DC and AC transmission. Televisions went through a similar period (in the infancy) with mechanical vs electronic televisions. Even now, you have competing tech that requires matching devices (NTSC, PAL SECAM).

Ah no - not matching devices, only matching technology. The significant difference (when compared to the Skype situation) being that anyone is free to develop devices using either technology.

Not exactly free. Some technologies you have to pay for to even get the specs. Talking of phones, Europe is 64 KBit/s channel, the USA is 56. The USA uses µ-law digitalization (companding algorithm), Europe A-law. International phone calls are not that easy to implement. Digital cellular phones in Europe use GSM, which was a project developed by a consortium of states, with full definitions of what you had to implement, even up to the colours and symbols of the hang-up/hang-down buttons on the terminals. It is not GSM unless you abide to the rules. As it was not developed by a private company, phone companies could be forced to implement it in Europe, yes or yes, and compatibility was ensured, and roaming across Europe worked from scratch (abusive pricing notwithstanding). It was so successful that other countries chose to use it as well, even the USA. But there you get isolated islands. Private enterprising, you know. ;-)

...

For the Linux desktop, it's a mix of Skype, Viber, Ekiga, and lately I've started tinkering with Telepathy. I'd prefer to roll it all into one client that allows me to connect to SIP, Skype and Viber... but... so far no luck.

Yeah, if only SIP was as popular as Skype.

Because it is not "click and shoot" install. Years ago you had to configure routers, it was not simple. And SIP was not the only protocol. SIP was what the Internet people proposed, the phone companies proposed different solutions. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iF4EAREIAAYFAlNozd8ACgkQja8UbcUWM1wkKQD/abtuxyi7xodMBnOrK1xEqNfC TVfz0m6zTtoqtdps3pEA/iGblxJEyygJPgxjc5EUZm2OCbagLzCiBHISyM9LKjEg =hh2Z -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2014-05-06 14:09, James Knott wrote:

Carlos E. R. wrote:

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For an obvious reason: it was 4 car batteries in series.

If you were to look at telephone company batteries, you'd realize they have little in common with car batteries and in fact even predate them.

I know. I have installed them things ;-) But they started with car batteries, 6 or 12 volts. Otherwise, they could have chosen any random number or elements cells.

BTW, I used to work for a telecommunications company and the -48V plant in the office I worked in provided about 7000 amps and could support that load for several hours. Not many car batteries are capable of that.

Someone I know let a screwdriver drop across the copper bars in one of the power distribution boxes. An entire island had no GSM service for hours. Unknown reason ;-) If you are going to say that the screwdriver should have the metal rod in a plastic leave, yes, it should. This is what happens with "expense cuts" and "subcontracting". Serves them well. They could have been working on the distribution box during the night, but... see above. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iF4EAREIAAYFAlNo1QkACgkQja8UbcUWM1wzLwD/V3zMJsBzyy4pcq+vBt56QtzD xiys7SOdo/uloaRbBjQA/2ilBAUKV6M8tnlp7nvfNgGA0cRlm228K6DD+UnOFfdn =TBpL -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2014-05-06 16:08, James Knott wrote:

Carlos E. R. wrote:

...

But they started with car batteries, 6 or 12 volts. Otherwise, they could have chosen any random number or elements cells.

Except phone batteries and telegraph batteries before them predate car batteries. It wasn't until the 1920's that cars used a starter motor and early engines used magnetos for the spark plugs. The first battery driven ignition systems appeared around 1910. Early cars used gas lamps for lights, so there was no need for an electrical system & batteries for the early vehicles. On the other hand, batteries in telecom use go back to the 1850s. So, it was impossible for those to have been car batteries. They simply didn't exist back then.

Ah, ok. Then batteries must have been grouped in sixes before cars. Although I believe early telegraph and phone did not use lead-acid rechargeable batteries, but plain, heavy, one use batteries. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iF4EAREIAAYFAlNo7+gACgkQja8UbcUWM1ysMwEAnl6u+S+fKxPGnhX6khWvIbzc gDvrizOr43chFnNbK3kA/A51Pf96nkkHXlZQIvypTai2WDjjZh4nEKp3HvqPG4zX =FJSU -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

Depends on how many you have. The typical battery used in large scale UPS's (for bridging whilst the generators get going) is a 24v truck battery. I have no idea how much such a collection can deliver, but when it needs to run cooling, lighting, disks and e.g. 3-4 IBM 3090s of the old kind, it's quite a bit. Usually they're only designed to hold the load for 5-10minutes though.

Batteries used for starting cars & trucks are not suitable for that type of service. Starting batteries are designed for high current, short term loads. Batteries for UPS are designed to be floating on the rectifier output and be ready to take over the load immediately and sustain it for as much time as required. Typical UPSs, as used with personal computers only last several minutes. Those used for telecom etc. have to carry the load for several hours or even days. Using the wrong type of battery may work in the short term, but premature failure is pretty much guaranteed. In the telecom office where I used to work, there were several battery strings and multiple rectifiers to keep them charged. If the commercial power should fail, standby generators would kick in and last as long as the fuel held out. As I recall, each cell was almost a metre tall and 50 - 60 cm square. They were mounted on steel racks and connected with very large cables. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

James Knott wrote:

Per Jessen wrote:

...

Depends on how many you have. The typical battery used in large scale UPS's (for bridging whilst the generators get going) is a 24v truck battery. I have no idea how much such a collection can deliver, but when it needs to run cooling, lighting, disks and e.g. 3-4 IBM 3090s of the old kind, it's quite a bit. Usually they're only designed to hold the load for 5-10minutes though.

Batteries used for starting cars & trucks are not suitable for that type of service.

Hmm, well, that's how I saw them used in the late 80s in a large datacentre installation. The generator was about the size of a large train engine. Maybe they weren't regular truck batteries.

Starting batteries are designed for high current, short term loads. Batteries for UPS are designed to be floating on the rectifier output and be ready to take over the load immediately and sustain it for as much time as required.

We're just now inthe process of getting a new 40KVA UPS installed, the batteries are standard 12V, nothing special about them. Looking at our much smaller per-rack 6KVA units, the batteries are also standard 6V or 12V units.

Typical UPSs, as used with personal computers only last several minutes. Those used for telecom etc. have to carry the load for several hours or even days.

Because they don't use generators?

Using the wrong type of battery may work in the short term, but premature failure is pretty much guaranteed.

I'm not sufficiently knowledgeable to discuss this, but Schneider/APC seem to disagree with you, they use standard lead accumulators. -- Per Jessen, Zürich (18.1°C) http://www.dns24.ch/ - your free DNS host, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Carlos E. R. wrote:

Talking of phones, Europe is 64 KBit/s channel, the USA is 56. The USA uses µ-law digitalization (companding algorithm), Europe A-law. International phone calls are not that easy to implement.

Phones in the U.S. and elsewhere run 64 Kb/s. What you're thinking of was when a voice channel was used for data and common channel signalling was not available. In that instance, only 56 Kb were available for data. These days, the full 64 K is available, though that technology is now on the way out, in favour of IP. The E1 used in Europe and elsewhere had signalling bits available outside of the data bandwidth. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On 05/06/2014 07:32 AM, Per Jessen wrote:

Carlos E. R. wrote:

...

...

...

...

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>Some early phones were purely acoustic for example.

wire-and-tin-cans ?

Air voice pipes in ships... Yep, good example too.

What about the sound powered phones used on ships? -- I may be crazy, but crazy is better than stupid. _ _... ..._ _ _._ ._ ..... ._.. ... .._ -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2014-05-06 14:32, Per Jessen wrote:

Carlos E. R. wrote:

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Not exactly free. Some technologies you have to pay for to even get the specs.

I guess you're referring to ISO standards, PCI ditto and such. I see no real problem with having to pay for that. I can still use them without being dragged into court.

Some companies build their own, different technology, just for that reason, at the cost for the client or impossible interconectivity.

...

Talking of phones, Europe is 64 KBit/s channel, the USA is 56. The USA uses µ-law digitalization (companding algorithm), Europe A-law. International phone calls are not that easy to implement.

For the end-user, it's not an issue and I don't need to use the same phone (or technology) as my old mum when I call her. (except if I wanted to use Skype).

It is, or was, for instance, it you traveled with your modem and needed to connect on the hotel. Or if you set offices on different countries, you needed to get local hardware for the phones. Say... I don't know currently, but British home phone lines used a separate ring copper line, because that line was separated from the voice lines at the entry box to the home. So the plug needed that separate pin. I don't know if this has changed. But the British are different: for instance, they had different power plugs on houses. When I traveled there and bought a gadget, years ago, the power cord had no plug. You had to buy that separately and connect it yourself, after learning what your place used - which at that time were probably the same in all new houses. As I say, I don't know if this is still true. The European Union has enforced some standardization. Like increasing the voltage from 220 to 230 in Spain, silently. And conversely, lowering from 240 to 230 on others, I hope. Not sure about this.

...

...

Yeah, if only SIP was as popular as Skype.

Because it is not "click and shoot" install. Years ago you had to configure routers, it was not simple.

I agree, but I still wish it was. (I don't remember having to do anything special to a router though).

I do... NAT is a problem to traverse. Depends on your router. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iF4EAREIAAYFAlNo2w8ACgkQja8UbcUWM1yYOQD/b7Du3uRzQDMftNOENEC7z8YM 23YeXw02Ol9hB8J5tLsA/iaEL+cjuDz4voOWpdE6R3Fqnb8354UcAIqpb+sDVEtc =x4vs -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

...

Say... I don't know currently, but British home phone lines used a

...

separate ring copper line, because that line was separated from the voice lines at the entry box to the home. So the plug needed that separate pin. Presumably a very long time ago? When I lived in London in the late 90s, we had plain 2-wire copper cable running up the outside wall, seemed to be dating back to the 50s.

I don't know about England, but where I grew up, party line phones had a third wire used for ringing and hook switch. How that 3rd wire was connected depended on which of the 2 parties you were. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On Tue, May 6, 2014 at 1:42 PM, James Knott wrote:

Per Jessen wrote:

...

AFAIK, most mains devices have long accepted 220-240V, such that they can be used around the world (except the US and other 115V countries).

Actually, they can be used in North America too, as house wiring here is 240/120, with 120V between one side and neutral and 240 between the 2 hot wires. Major appliances, such as stoves run on 240V, but it's also used in many outlets where heavy loads are expected. With a duplex outlet, one would be connected to one hot wire and the other to the 2nd, with them both sharing the neutral. It would be a trivial matter to convert one of those to a 240V outlet.

I haven't been following this thread, but saw the above. Do any of the 220-240v mains devices assume one of the legs is ground? A lot of US devices over the last couple decades do. They connect that leg to the outside case of the device. Typical examples are drills / saws / etc. Using a 2-phase US circuit to simulate a 1-phase 220v circuit would be dangerous if there are devices that depend on one of the legs being ground. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On Tue, May 6, 2014 at 2:10 PM, James Knott wrote:

Greg Freemyer wrote:

...

Do any of the 220-240v mains devices assume one of the legs is ground?

A lot of US devices over the last couple decades do. They connect that leg to the outside case of the device. Typical examples are drills / saws / etc.

Using a 2-phase US circuit to simulate a 1-phase 220v circuit would be dangerous if there are devices that depend on one of the legs being ground.

Any devices that do that cannot have any exposed metal parts that aren't double insulated from the power conductors. Those with metal cases, such as drills etc. are supposed to be grounded separately from the power conductors.

James, We're way off-topic, but if the power legs are doubly insulated from the chassis, why does it matter which leg is ground? (I'd google, but I don't what to search for. I did find it is called a class II device, but not the reason for not letting the plug work both ways.). I had assumed they were using that one leg as both the return and as ground. Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On Tue, May 6, 2014 at 2:26 PM, Per Jessen wrote:

...

Using a 2-phase US circuit to simulate a 1-phase 220v circuit would be dangerous if there are devices that depend on one of the legs being ground.

I suspect you mean neutral instead of ground?

At least here neutral and ground are very similar. A standard US household circuit breaker panel has: phase 1 hot phase 2 hot neutral - return ground The neutral & ground are actually tied together inside the circuit breaker panel. Further, both are often connected to a copper cold water line. By code that has to happen close to where the cold water line enters the building. I know my house works that way, but there is also a second ground spike driven directly into the ground that is also tied to the circuit breaker panel ground and neutral. Thus in theory the "ground"/neutral is actually a part of the 120volt circuit. and both the ground lines and the neutral/return should have close to zero volts differential to the outside dirt (ground). The fundamental difference here is that the ground lines running to every plug don't typically carry any current except in a failure mode. The neutral/return is meant to carry current routinely. With a "class II" plug, the active legs slots are slightly different sized so that a device can know which leg is neutral (close to ground) and which leg is hot. http://upload.wikimedia.org/wikipedia/commons/d/dd/OutletPlug.jpg fyi: if a circuit breaker panel is perfectly balanced the electrons flow only in the 2 hot lines and in the neutral. No electron movement would take place in any of the ground lines including the real ground outside. Such perfect balancing is impossible to achieve so electrons are moving in and out of the earth continuously in a US system. I assume the same is true for the EU. Greg -- Greg Freemyer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On Tue, May 6, 2014 at 3:23 PM, Per Jessen wrote:

Greg Freemyer wrote:

...

On Tue, May 6, 2014 at 2:26 PM, Per Jessen wrote:

...

...

Using a 2-phase US circuit to simulate a 1-phase 220v circuit would be dangerous if there are devices that depend on one of the legs being ground.

I suspect you mean neutral instead of ground?

At least here neutral and ground are very similar.

A standard US household circuit breaker panel has:

phase 1 hot phase 2 hot neutral - return ground

The standard household supply here has one more phase, otherwise the same.

...

The neutral & ground are actually tied together inside the circuit breaker panel.

Not here, not at all. Any current running to ground is a fault, and will cause the residual-current circuit breaker to pop. According to wikipedia, it is called a "Ground Fault Circuit Interrupter" where you live.

We have GFCI plugs and they are typically required near water (sinks/kitchens/bathrooms). But here the GFCI is only used after the circuit breaker. James can correct me, but I am fairly sure any current flowing in the neutral lines inside a building is transferred to the ground at the circuit breaker and from there it flows to the outside ground/earth/dirt. The phases are 180 degrees out, so if you have exactly a 100 amps of load on both phases, the net electron flow on the ground line leading to the dirt is zero. But in general the ground/earth/dirt is the return back to the power station.

...

Further, both are often connected to a copper cold water line. By code that has to happen close to where the cold water line enters the building. I know my house works that way, but there is also a second ground spike driven directly into the ground that is also tied to the circuit breaker panel ground and neutral.

Wow. I'm familiar with the ground spike and the clamp on the cold water pipe, but not the rest.

I am 100% sure that the outside ground/earth/dirt is connected to both that inside ground lines and the neutral lines at the circuit breaker panel. I am not 100% sure there is not also a copper neutral return line to the power company, but I don't think there is.

...

Thus in theory the "ground"/neutral is actually a part of the 120volt circuit. and both the ground lines and the neutral/return should have close to zero volts differential to the outside dirt (ground).

The fundamental difference here is that the ground lines running to every plug don't typically carry any current except in a failure mode.

Right, same here.

...

The neutral/return is meant to carry current routinely.

Right. So why are they tied together in the circuit breaker panel?

Because the outside dirt is the fundamental return as I understand it. With a standard single phase 3 wire setup, the ground line is tied to the device chassis and the power runs in the hot and return. Because of that if you look at a standard US household in wall electric cable, the hot and return are individually insulated. The ground is not although it is inside the overall cable sheathing.

...

fyi: if a circuit breaker panel is perfectly balanced the electrons flow only in the 2 hot lines and in the neutral. No electron movement would take place in any of the ground lines including the real ground outside.

Right - dunno if I would call that perfect, for the single phase circuit it's just normal. In the 3-phase setup, with a perfectly balanced load, you have no return current on the neutral.

...

Such perfect balancing is impossible to achieve so electrons are moving in and out of the earth continuously in a US system. I assume the same is true for the EU.

A bit out of my field, but I don't think so. Current running to ground will cause the FI Schultzschalter to pop.

One of these: http://w3.usa.siemens.com/powerdistribution/us/en/product-portfolio/circuit-... http://www.conrad.ch/ce/de/product/628056?insert=UP&WT.mc_id=googleshopping_b2c_chd&WT.srch=1&gclid=CLfb1t6AmL4CFZShtAodgyoAaw http://www.distrelec.ch/de/FI-Schutzschalter-63-A-300-mA-4-polig-415-VAC-Sch...

Again, I'm petty sure in the US we routinely have electron flow in the outside ground, but not in the inside / post circuit breaker ground lines. I am pretty confident we don't have a GFCI or equivalent monitoring the outside ground line.

-- Per Jessen, Zürich (18.1°C)

Greg -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Greg Freemyer wrote:

...

Not here, not at all. Any current running to ground is a fault, and will cause the residual-current circuit breaker to pop. According to wikipedia, it is called a "Ground Fault Circuit Interrupter" where you live.

We have GFCI plugs and they are typically required near water (sinks/kitchens/bathrooms).

Yes, same here I believe.

But here the GFCI is only used after the circuit breaker. James can correct me, but I am fairly sure any current flowing in the neutral lines inside a building is transferred to the ground at the circuit breaker and from there it flows to the outside ground/earth/dirt.

I've done some reading up on this, and you appear to be correct in principle. In practice however, a neutral wire is always fed to the household consumer as a) it is often difficult to establish sufficient grounding and b) there is a risk of the return current running in the upper layer of the soil, causing significant dangers to humans and animals near the ground spike. (apparently this has killed horses in the past). Source: http://da.wikipedia.org/wiki/Vekselsp%C3%A6nding_(3-faset)#3-faset_vekselsp.... I'll go and check our own circuit breaker closet later. -- Per Jessen, Zürich (12.7°C) http://www.dns24.ch/ - free dynamic DNS, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

"An example of application is a local distribution in Europe, where each customer is fed a phase and a neutral." The difference in North America is instead of using one phase to the customer, a transformer is used, with the secondary centre tapped to ground, with the two hot wires 180° apart. With this method you could say 6 phases are available.

-- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Carlos E. R. wrote:

Ah, that's explains some things for me, thanks.

No, it is 3 phases (look at the waveforms with a scope), but each one is split in half voltages. Interesting trick.

The homes are still fed from a single phase. With the distribution system, a higher voltage is used to carry the power into the neighbourhood, with transformers used to reduce the voltage to household levels. In North America, the difference is the centre tap, with two wires, instead of one.

The reason for the three phase distribution is that you can carry more current with less copper (4 wires instead of 6 for the same total load).

With the split system, assuming loads balanced on both sides, there is no difference. With an imbalance, the neutral carries the difference. In no case would the current ever exceed that in the European system.

The method you describe has to be short distance, and provides the advantage of having two voltages in the house, normal and "heavy duty". A 110 AC line is less dangerous for electrocutions, but worse on heavy loads because of fire risk (higher current).

Typical wiring here is 15A (sometimes 20) per circuit, though some circuits, such as stoves & dryers are higher. Just use the right size wire and there's no more risk. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

...

...

breaker panel. Not here, not at all. Any current running to ground is a fault, and will cause the residual-current circuit breaker to pop. According to wikipedia, it is called a "Ground Fault Circuit Interrupter" where you

The neutral & ground are actually tied together inside the circuit live.

Please note he said they're tied together at the breaker panel. That (or rather the entrance panel) is the only place where ground & neutral connect. Thus, the neutral is the return wire and the ground is there for safety. A fault may cause current in the ground wire. BTW, the GFIs rely on unbalanced current in the hot & neutral, rather than current in the ground wire, as the fault may be through something else other than the ground wire. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

...

Actually, they can be used in North America too, as house wiring here

...

is 240/120, with 120V between one side and neutral and 240 between the 2 hot wires. Major appliances, such as stoves run on 240V, but it's also used in many outlets where heavy loads are expected. Ah, okay, that's like our 3-phase with 380V between two phases.

No. It's different. 240/120 wiring has opposite polarity on the 2 hot wires, so it's 240V between the 2 hot or 120 between either hot & neutral. The 2 hot wires are 180° apart. With 3 phase, the 3 hot leads are 120°. With 120V wiring, 3 phase is called 208V, as that what the hot to hot voltage is. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

Carlos E. R. wrote:

...

As I say, I don't know if this is still true. The European Union has enforced some standardization. Like increasing the voltage from 220 to 230 in Spain, silently. And conversely, lowering from 240 to 230 on others, I hope. Not sure about this.

I'm not sure, I don't think the EU has done anything about that at all, more likely the IEE or IEC.

It looks like it was the EU, although it doesn't explicitly say so: http://en.wikipedia.org/wiki/Mains_electricity#Standardisation Still, the tolerances used mean that no actual changes were required, afaict. -- Per Jessen, Zürich (18.3°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Carlos E. R. wrote:

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256

On 2014-05-06 19:58, Per Jessen wrote:

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Per Jessen wrote:

...

It looks like it was the EU, although it doesn't explicitly say so:

http://en.wikipedia.org/wiki/Mains_electricity#Standardisation

Still, the tolerances used mean that no actual changes were required, afaict.

My bulbs started to burn out earlier :-)

That happened to us in England in the 90s. We had more bulbs blow in four years in London than I had had blown in my entire life prior. We switched to energy saving CFL one we figured out that something was dodgy with the mains. -- Per Jessen, Zürich (18.7°C) http://www.hostsuisse.com/ - virtual servers, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Per Jessen wrote:

...

That is a real "gotcha". If the majority of your contacts are using

...

Skype (on Windows/OSX/Android)... you're a bit stuck. Yep, that's what I meant. It's a pity that Skype only works with Skype, imagine what that would have done to early telephony if you'd needed matching telephone devices.

Another possibility is Google Hangouts. It's available to anyone with a gmail account. In addition to phone and tablet apps, you can use a browser by adding a plugin. I prefer it to Skype. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Carlos E. R. wrote:

The problem is precisely that you need a browser, no app available. And once you are logged into google, they track everything you do with your browser.

On computers, you need a browser vs dedicated app. On phones & tablets, it's a dedicated app either way. Also, how do you know Skype isn't tracking you? Do you really trust Microsoft (Skype owner) to not do that? -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Am 06.05.2014 14:34, schrieb Carlos E. R.:

... And, in the case of google talk in android, you need to be logged into google account first, so they track your entire phone activity. Well, maybe not phone calls.

phone calls, sms, photos, notes, contacts, gps position - whatever is in your phone. Wasn't their slogan: Don't do no evil ? It's so sad that there is no pure linux phone, we can only choose if we give our privacy to apple, m$ or big perv brother google. Of course even on a linux phone the NSA for sure will put enough pressure on chip manufacturers to give them access... -- Daniel Bauer photographer Basel Barcelona professional photography: http://www.daniel-bauer.com google+: https://plus.google.com/109534388657020287386 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Le 06/05/2014 18:15, C a écrit :

On Tue, May 6, 2014 at 4:56 PM, Daniel Bauer wrote:

...

phone calls, sms, photos, notes, contacts, gps position - whatever is in your phone. Wasn't their slogan: Don't do no evil ?

It's so sad that there is no pure linux phone, we can only choose if we give our privacy to apple, m$ or big perv brother google. There is though... well, not pure Linux, but OpenMoko is a phone OS with and open stack.

http://wiki.openmoko.org/wiki/Main_Page

And then there's this phone: http://neo900.org/ which claims to be open... I haven't really looked into it, but... if what they claim is true....

...

Of course even on a linux phone the NSA for sure will put enough pressure on chip manufacturers to give them access... It does make you wonder about the Ubuntu phone (if it ever arrives), and what concessions they've made but not told anyone.

C The Neo900/OpenMoko is very expensive... and the GSM chipset is neither free or secure. Any GSM device will never be.

When China soldiers will be in our streets, think Wifi + Raspberry-pi-like : http://en.wikipedia.org/wiki/PirateBox -- : ` _..-=-=-=-.._.--. Dsant, from Lyon, France `-._ ___,..-'" -~~` __') forum@votreservice.com jgs `'"---'"`>>"'~~"~"~~>>'` =====================```========```======== -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 06/05/14 13:04, Carlos E. R. wrote:

For instance, one popular thing with mobile phones is an app that tracks your walks. You activate the app, you can see the path you took on a map, how many calories you spent. You can share them with friends

Then they aggregate the data obtained. Then business know whether they have to offer more jogging or running shoes in a particular city, where to put watering holes, etc. It is an astonishing market.

I use openGPS tracker on my Android phone. Hopefully I'm invisible to the snoopers. - -- Bob Williams System: Linux 3.11.10-7-desktop Distro: openSUSE 13.1 (x86_64) with KDE Development Platform: 4.13.0 Uptime: 06:00am up 2 days 20:57, 4 users, load average: 0.02, 0.05, 0.05 -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iEYEARECAAYFAlNo1JgACgkQ0Sr7eZJrmU7qmQCdHMeKCfV8Lm+RZvsKnmuYACuo o9EAn19dJqN8Wzs6gREVZjGZNeuf/gVG =x7LC -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Harrie Baken wrote:

...

Another possibility is Google Hangouts. It's available to anyone with a gmail account.

It's available to anyone with a Google account.

Isn't that what I said? A GMail ID is used for everything you do with Google that requires logging in. For example, when you get an Android device, you register it to your GMail account. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Harrie Baken wrote:

Hallo James, op 07-05-14 13:51 schreef je:

...

Harrie Baken wrote:

...

...

Another possibility is Google Hangouts. It's available to anyone with a gmail account.

It's available to anyone with a Google account.

Isn't that what I said?

No, you didn't. :-D

...

A GMail ID is used for everything you do with Google that requires logging in. For example, when you get an Android device, you register it to your GMail account.

https://accounts.google.com/SignUpWithoutGmail

Where is says: " One account is all you need A single username and password gets you into everything Google." The first Google account many people had was GMail, as that's all that was available. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Harrie Baken wrote:

I don't get it. Most people did or do have an other mail address available. Even with a hotmail address one can get a Google account. I suspect most people assumed a Gmail account was required and didn't check if that was really so.

I had a GMail address long before I had any other use for it. It has never been my primary address. However, many got a GMail address, just like others got a Hotmail or Yahoo! account. It was simply a free email account not tied to any internet provider. With "not available", I was referring to other Google services, not email providers. Years ago, Google was a search engine only and they then started offering free email. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Hallo Carlos, op 07-05-14 14:36 schreef je:

On 2014-05-07 13:56, Harrie Baken wrote:

...

Hallo James, op 07-05-14 13:51 schreef je:

...

Harrie Baken wrote:

...

...

Another possibility is Google Hangouts. It's available to anyone with a gmail account.

It's available to anyone with a Google account.

Isn't that what I said?

No, you didn't. :-D

...

A GMail ID is used for everything you do with Google that requires logging in. For example, when you get an Android device, you register it to your GMail account.

https://accounts.google.com/SignUpWithoutGmail

A gmail id and a google account is the same thing, despite the names. You simply activate the full thing or not.

I think Google want's everybody to believe that, so they can make the whole bloody world even more dependent of their monstrous company. But it's BS. My username for my Google account (phone, webmasters support, G+, etc.) is [something]@tekstbaken.nl. Harrie -- Harrie Baken | Tekstbureau TekstBaken Copy-editing - proofreading - seo http://www.tekstbaken.nl/ Registered Linux user #366560 | openSUSE 13.1 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Hallo Carlos, op 07-05-14 15:30 schreef je:

On 2014-05-07 15:13, Harrie Baken wrote:

...

Hallo Carlos, op 07-05-14 14:36 schreef je:

...

...

A gmail id and a google account is the same thing, despite the names. You simply activate the full thing or not.

I think Google want's everybody to believe that, so they can make the whole bloody world even more dependent of their monstrous company. But it's BS. My username for my Google account (phone, webmasters support, G+, etc.) is [something]@tekstbaken.nl.

Yes, you can get a google account with a different email address - but you do get a corresponding gmail folder as well, typically forwarded to your given address.

You scared me to death, so sent a mail to [something]@gmail.com but the answer was: Remote-MTA: DNS; gmail-smtp-in.l.google.com Diagnostic-Code: SMTP; 550-5.1.1 The email account that you tried to reach does not exist. (With the same "something" of course.) A different (probably the same) methode is checking at https://www.google.com/accounts/recovery (with the option: I don’t know my password). What a relief again - no gmail address.

I have that with my ieee.org address, it is handled by google now.

I feel sorry for you. ;-D Harrie -- Harrie Baken | Tekstbureau TekstBaken Copy-editing - proofreading - seo http://www.tekstbaken.nl/ Registered Linux user #366560 | openSUSE 13.1 -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Anton Aylward wrote:

...

...

One alternative client that some people (in my circles at least) are starting to use is Viber.

I've seen that mentioned, but AFAIK it's only yet-another-voip solution. For the mobile it's seems downright silly, but maybe given the right kind of subscription ?

It depends on what you mean by 'silly'.

In this context, "waste of money/resources", but like I said, it depends on the subscription. For instance, in my company we have a group-call setup that means all calls between company mobiles are free. Using a VoIP app and hence using up data volume instead would be silly.

The Phone companies in my area have a basic service, be it wired or some kind of VOIP "home phone" that costs between $30 and $50/month depending on your plan. By comparison my VoIP service costs me $2/month and about $0.005/min. That rate applies thought north America and Europe and all except some 3rd world and very regional areas of India, Africa and China.

Yep, we have something similar.

The VoIP over wifi capability is basic in the Android phone; I don't need to install an app.

Really? I have an HTC Android, I did once play with VoIP on it, but I'm pretty certain I needed a client-app. -- Per Jessen, Zürich (20.5°C) http://www.hostsuisse.com/ - virtual servers, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On 5/6/2014 10:26 AM, James Knott wrote:

Per Jessen wrote:

...

Really? I have an HTC Android, I did once play with VoIP on it, but I'm pretty certain I needed a client-app.

Android phones have a built in VoIP app.

Which only works on WIFI, because most carriers demand it that way. If you want it to work everywhere, you need a third party package, like CsipSimple, which will handle just about any voip/sip provider. -- _____________________________________ ---This space for rent--- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

On 05/06/2014 12:59 PM, Per Jessen wrote:

Anton Aylward wrote:

...

The VoIP over wifi capability is basic in the Android phone; I don't need to install an app.

Really? I have an HTC Android, I did once play with VoIP on it, but I'm pretty certain I needed a client-app.

IIR Sip features were added in Android 2.3 (API level 9) http://developer.android.com/reference/android/net/sip/package-summary.html Here's a guide to setting it up. https://www.callcentric.com/support/device/android/sip_client The end result, after I followed this, is that whenever I make a call and have a IP connection as well I get asked if I want to use the cell/voice service or the VoIP service. In the limiting case, if you are someone who is always within range of a wifi service, perhaps confined to home because of a physical disability, you don't need a regular phone, your cell phone can do the VoIP over the wifi. Alternatively, if you are on one of the limited plans and want to make calls without burning up your precious minutes, you can make VoIP/wifi calls from home of the local coffee shop :-) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Le 06/05/2014 09:36, C a écrit :

On Tue, May 6, 2014 at 9:06 AM, Per Jessen wrote:

...

mk-lists@email.de wrote:

...

I am wondering whether KTp is actually already an alternative to Skype these days… Any VoIP solution is an alternative, it's only a matter of who you want to talk to :-( That is a real "gotcha". If the majority of your contacts are using Skype (on Windows/OSX/Android)... you're a bit stuck.

One solution would be a "one click install" first time : * Open source repositories (With OpenSUSE it's easy, isn't it ?) * Email attachment "in a smart way" (secure, easy... still to implement I think) * Ask your friend to go to a web site : one click and SIP phone software is ready (Citrix do that easy for W$ in corporates) * ? And after installation, don't forget automatic configuration. -- : ` _..-=-=-=-.._.--. Dsant, from Lyon, France `-._ ___,..-'" -~~` __') forum@votreservice.com jgs `'"---'"`>>"'~~"~"~~>>'` =====================```========```======== -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org

Stefan Gofferje wrote:

On 05/05/2014 11:01 PM, mk-lists@email.de wrote:

...

I am wondering whether KTp is actually already an alternative to Skype these days…

Who has experience with KTp regarding audio/video connections compared to Skype?

I'm using the asterisk PBX for over 10 years now at home.

We're using Asterisk for business+home use for more than 8 years. Initially with ISDN clients, now only with VoIP. -- Per Jessen, Zürich (18.2°C) http://www.dns24.ch/ - your free DNS host, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org