Long-Distance WiFi Device

[colemj]

With the computer plugged in to a power source, the power draw from the internal wireless or an external adapter will be the same whether they are turned on/connected or not as long as the computer battery is not fully charged. However, the length of time it takes to fully charge the battery will be increased when they are turned on/connected. So there is a power usage associated with these devices - they are not "free".

Even so, the amount of discussion around a couple hundred milliamps is confusing (amusing?) - if you want wifi, you accept a little bit of power usage. If you want to be able to see your monitor in full light, you accept the power usage it takes to turn the brightness up (I could go on with more examples...).

To be pedantic, IF you decide to power manage your boat by fully charging the computer battery using a DC/DC converter AND only using internet from the computer when it is running on its batteries AND the internet device you use is plugged directly into the computer AND your internal wifi is turned off, then you will use less energy with an ethernet client bridge than you will with a USB client adapter.

About 200mA per DAY (depending on your computer and length of time on wireless).

Mark

[ArmyChief]

You can also:

Use a Ad-Hoc network from your laptop and connect as many wifi devices as you want (don't need a router)

Use a software package like
www.connectify.me/

[richardhula]

Buy Bullet & 9db omni from these guys. Buy 15 metres of outdoor quality Cat5e with RJ45 connectors. A little bit of cable work & you have working system for under $120.

You still have to procure antenna bracket but that should be well within the $130 minimum you save.

WiFi-stock also have a UK based operation & offer the Bullet M2HP with faster 802.11n capability for same price as 2HP. I understand this may be slightly slower with 802.11g connections, but prefer the hedge against redundancy.

Finally both branches offer cheap & neat AC (US or UK) powered POE device if you have AC available or are using the system land based.

[mlahrkamp]

This portion of this topic started based on a claim that running a USB device has no impact on a laptop's battery. This evolved into some math demonstrating that wasn't true. The amount of power draw is not great but there is an impact.

While today's typical laptop can be used to create a hotspot, using this as a solution is a big overkill and electrically wasteful compared to a purpose built device.

Wi-Fi is two way radio. It requires power to transmit. Anytime it is turned on, power consumed is increased. That's why a button is often on the laptop to disable it and save the battery power when not in use.

[ArmyChief]

Originally Posted by mlahrkamp

This portion of this topic started based on a claim that running a USB device has no impact on a laptop's battery. This evolved into some math demonstrating that wasn't true. The amount of power draw is not great but there is an impact.

While today's typical laptop can be used to create a hotspot, using this as a solution is a big overkill and electrically wasteful compared to a purpose built device.

Wi-Fi is two way radio. It requires power to transmit. Anytime it is turned on, power consumed is increased. That's why a button is often on the laptop to disable it and save the battery power when not in use.

I understand the initial intent of this topic..I've been involved quite a lot. However, using other PC's and iphones..etc..etc..WAS brought up. So since the door was opened by someone OTHER than me. I wanted to comment on that statement. the person who brought that issue up, must not have been thinking about power consuption we can only assume

[mlahrkamp]

Originally Posted by richardhula

Buy Bullet & 9db omni from these guys. Buy 15 metres of Cat5e with RJ45 connectors. A little bit of cable work & you have working system for under $120.

You still have to procure antenna bracket but that should be well within the $130 minimum you save.

Certainly a DIY is possible. Add shipping, the price of the bracket, and the added price of PVC sheathed, UV protected, weatherproof outdoor rated cat5e over regular cat5, some lithium dielectric grease and the savings may dwindle. You may also need a connector crimping tool or splicing junction box (if you plan on a permanent install). Then there's the support aspect. Many of the resellers who use Bullets also put their own software onto the devices to make it much easier to use since the native Bullet firmware is designed primarily for AP use. Complete kits with warranty can be found on the internet for around $200. So it becomes more a matter of what your time is worth and the level of technical skill possessed.

[kiltym]

Originally Posted by mlahrkamp

While today's typical laptop can be used to create a hotspot, using this as a solution is a big overkill and electrically wasteful compared to a purpose built device.

Perhaps another perspective.

OK. I own a laptop on my boat, I buy a WiFi system. Great. Then I think about things. My partner has a laptop too. It would be great if we could both get online at the same time.

I have a few options, one, I can buy some more hardware (router), wire it into the boat, use more electricity, wire it to the client bridge and try to configure a client bridge and router to talk to each other nicely (which can be challenging), or I can use a built in feature on Windows and Mac to allow me to share my internet connection for free in about 10 minutes.

That seems pretty simple to me, and not overkill, and has been working fine for well over a year on my boat. Both options will work, but to call Connection Sharing overkill and wasteful was a bit harsh I think.

And as will be pointed out again, and has been already many times, yes, the computer needs to be on. So if your primary source for internet is not a computer, than you are now in the realm of routers and client bridges (or repeaters). If you mostly use a computer to access the internet, USB and Internet Sharing works splendidly (also with iPhones,etc), is free, requires little technical knowledge, and no additional electricity.

Again, about electricity too . If I am using my laptop to get online, with a USB or Ethernet based device, lets assume the power consumption is equal. I hope we can agree. I then have 2 options, one, use something already on my computer with no additional electricity draw, or add hardware, which does need more electricity. So again, there are multiple perspectives on the power draw on these systems.

Its all about options, and I think both options are certainly viable. You sell what you sell Mike because you believe its the best choice. That's great. But, there are other choices available, and they will work well for people too.

Mark

[mlahrkamp]

Hey Mark,
Everybody has a different perception of the best system, agreed!

Now, I also agree that the power draw will be about equal for any system.

However, using your internal laptop Wi-Fi device as a hotspot will increase the power consumption. Nothing is for free. It may be that the cost is in reduced time between charging.

Second, if both of you are on at the same time, the world is good. But what happens when only the other person wants on, and not the owner of the laptop that's creating the hotspot. If it's a laptop, then simply move the USB plug, right? You're still good. But if it's a device that has no USB (or ethernet) connection, you'll need to fire up that hosting laptop, no? That's where I suggested that a laptop being used as a hotspot was a bit of on overkill and a purpose built device is more efficient.

[ArmyChief]

I can see the logic about hotspots and laptops being left on. My question would be this

In your scenario above, a user OTHER than th elaptop wants to use the internet wirelessly. If you close the lid on your laptop (having hibernate & sleep turned off)and of course most if not all mobile CPU/chipsets used in laptops throttle everything back when not in use. Also, the LCD/LED screen will not be lit since the lid is closed. then you have the Ad-Hoc/SW running for the WiFi. Is that really going to use more maybe even less..then a dedicated Hotspot WAP?

Also. as you mentioned, the original intent of this thread was long-range wifi, not distance vs power consumption. This is not like the movie Apollo 13 where they had to do scenario's for power uses or they would not get back to earth.

Distance of connectivity have a lot of factors...many have been mentioned in this thread.

Also, EIRP....love this term. Reminds me of the days at a flea market and seeing 2000 WATT amps for cars (12 vdc systems) and you look on the box and it says 2000 Watt PMPO and its got a 30 amp fuse.....LOL

Just make sure when your buying a Wifi adapter, booster, antenna..you are comparing apples to apples (EIRP vs EIRP, or Watts from the device to Watts from the device..etc..etc)

[hellosailor]

The Biquad antenna provides supposedly 12db of gain, which is not unusual for that type of design.

ALL THE REST is not really gain, it is just the power of the USB transceiver being sold with the antenna. This is NOT AN ANTENNA, it is a RADIO PACKAGE WITH ANTENNA.

The radio offered is a "23db" model, which is roughly a 200mW radio. Reasonably powerful for the job, especially compared ot the 25mW radios in many laptops.

To "custom build" this into a 45db gain SYSTEM using the same antenna, there's no magic, you just substitute a more power radio, available in 400mW, 500mW, and 1W sizes from many makers. Except, you'd need a 2W (2000mW) radio to get 45db of system gain, and that would be twice the maximum legal power in many places.

With WiFi, you also need to remember that every nation has their own power limits, and if you are tossing out more than one watt of "ERP" (effective radiated power as measured at the antenna after all gain) you may be looking at penalties. A one watt radio plus a gain antenna...isn't always going to be legal. A two watt radio plus a gain antenna...probably won't be sold for $45, microwave power costs more than that.

[ArmyChief]

Very good info sir sailor

[capt_douglas]

I went with the PepWave for two reasons: any number of computers could be connected as long as they had the WEP code; and it worked off an external power source, i.e. not the laptop's USB/Ethernet power. That gives us the flexibility to use the computer from most any location within range of the antenna, prolonged battery life, and important to me, didn't load down the USB/Ethernet ports, thereby possibly degrading the other USB items attached to the computer.

Given the choice of higher power output or higher antenna gain, I'll take the antenna gain over power output any time. I'm somewhat leery of combined units and their "power output" specifications. Is that effective radiated or power fed to the antenna? The PepWave's specs are 400mw into a dummy load. Couple that to a 9db gain antenna and the effective radiated power should be about 3W.

[VVD]

Does anybody know if there is a mount (female) that screws on the Enginius antenna which then can connect with a standard Shakespeare rail mount 1',14 threads Male.

Also has anybody cut the USB cable from the Alpha WiFi Adapter so is can be snaked from outside thru a coax cable hole in the hull back to the nav station and than reconnect it to the male USB plug.

Thanks, Vincent s/v MAKAI

[hellosailor]

Vincent, I would have to think that adapting the typical WiFi antenna mount to the much larger Shakespeare rail mount, if it exists, would create a horrible impedance bump and signal loss in the cable. I wouldn't even consider it.

OTOH cutting and splicing a USB cable (and that one I'd solder not crimp since two of them are high speed data cables) would create fewer problems. But even better, if you find the cables, would be to use a miniUSB or microUSB fitting at one end of the USB cable, and then a reversing extension to the other standard USB fitting. That way there's no soldering and if you need to pull itback through, you just unplug and pull.

If you go with soldering...instead of splicing the cable, I'd try to slice the rubber off one end first, and do the soldering right at the terminal end, where there's some type of solder/weld connection anyway. That way you're replacing a connection, instead of adding one. Less chance of signal degradation.

Although...you may be able to get a "cable clam" waterproof deck fitting that's big enough to slip a standard USB cable end through it. Best of all--no cutting, just money. :-)

[richardhula]

I've seen Ubiquiti Bullet 2HP offered as 1 watt max (30dBm) Tx power version, instead of usual 800mw.

I note that Ubiquiti site quotes spec for only one model stating 29dBm +/- 1dBm when in slower 802.11b mode.

I know the odd dB is going to make little difference but wonder if I can assume that those advertised as 1 watt are just selected ones, tested to produce the extra dBm from a batch?