|
|
23-08-2010, 12:11
|
#526
|
Marine Service Provider
Join Date: Jan 2010
Location: Toronto
Boat: Beneteau First 40
Posts: 78
|
PoE
Hi Jack,
I don't think I said anything about PoE. I was comparing USB to Ethernet.
Ubiquiti devices operate with a voltage range of 10-24V allowing them to be direct connected to a 12V power source, so no need for the inefficiencies of an inverter/injector. Their power draw, from real measurements, is about 200-300mA @ 12.75VDC. This draw at 300' does introduce some voltage loss, but is still within their acceptable operating range. Now most masthead installations will be less than 60' where loss is almost negligable, but the ethernet spec is still valid and 300' is achievable (although likely to never be tested on most cruising boats).
My last sentence suggested using a downstream wireless router for wirelessly connecting effectively creating a repeater. A true repeater cuts bandwidth by half by having to rebroadcast everything it receives (desired or not) onto the same channel at the same power thus reducing throughput for everyone using the hotspot or who happens to be sharing the same channel to another hotspot. A receiver connected to a downstream wireless router would only rebroadcast the traffic intended for a recipient that's wirelessly connected to it. And it can use a different channel at significantly lower power. Additionally, a repeater would need to establish a new link to the hotspot for every device connecting, whereas a downstream router system would only establish a single link, thus further cutting down on hotspot traffic. A downstream router is pennies in cost as compared to a true repeater device.
Of course, even considering a repeater device or downstream router is much more difficult for a USB based device and would require a computer to be on all the time. My comparison suggested that a USB device is suitable for a one-to-one connection scenario and ethernet was easier at making a connection available to multiple users simultaneously.
__________________
Mike L
|
|
|
23-08-2010, 12:52
|
#527
|
Registered User
Join Date: Jul 2010
Location: North Port, FL
Boat: Yamaha AR192
Posts: 297
|
Quote:
Originally Posted by captainmark55
|
Did you ever ASK how he boosted it? 10 dbi is a hell of a boost..let alone a biquad with 35 dbi. Do a google search on biquad wifi antenna's and look at some of th eREPUTABLE wireless hobbiest sites..with engineers on there...with THEIR designs and see what they say is a realistic dbi gain for a biquad.
Quote:
Originally Posted by captainmark55
all i know is that it works great, i dont know about the technical details, for the money it was worth a try and it suits me fine!
|
Well, then if thats all that matters..your happy and he's happy...great end of story
|
|
|
23-08-2010, 13:13
|
#528
|
Eternal Member
Join Date: May 2003
Location: Ft. Lauderdale, FL
Boat: Vancouver 36 cutter????
Posts: 620
|
I've been using a PepWave SURF-400 [ Pepwave Surf ] unit for more than a year and have had zero problems with it. The software installs easily and the display give a good indication of the signal strength.
The model I use is rated at 400mw output and needs 7W@12V to make it work. The unit's not waterproof but I ran a cable to a 9db antenna and have had no problems with the setup. It's been my experience that the stronger the signal the faster the connection and the Surf-400 seems to see a lot more wifi signals than most. The only downside that I can see is that it's 802.11b/g but not /n.
I looked at USB and POE (Power over Ethernet) models but the power output of those units wasn't as high as the Surf-400 and I wondered about loading the USB/Ethernet heavily. It's been my experience that a high gain antenna and moderate power can give a considerable range boost, making connections more consistent.
Since the Surf runs on 12V there's no problem with wall warts going bad or the need for an inverter.
__________________
Capt. Douglas Abbott
USCG/MCA IV/M.I./C.I. 500-ton Oceans
|
|
|
23-08-2010, 13:49
|
#529
|
Registered User
Join Date: Jul 2010
Location: North Port, FL
Boat: Yamaha AR192
Posts: 297
|
Quote:
Originally Posted by capt_douglas
I've been using a PepWave SURF-400 [ Pepwave Surf ] unit for more than a year and have had zero problems with it. The software installs easily and the display give a good indication of the signal strength.
The model I use is rated at 400mw output and needs 7W@12V to make it work. The unit's not waterproof but I ran a cable to a 9db antenna and have had no problems with the setup. It's been my experience that the stronger the signal the faster the connection and the Surf-400 seems to see a lot more wifi signals than most. The only downside that I can see is that it's 802.11b/g but not /n.
|
Cpt Douglas, I clicked on the buy now from your pepwave site and the unit you bought is $149.00 U.S. Just so yo know, you can buy a Alfa AWUS036H (tested adn very well known good unit...rated at 1000mW (1 Watt) for less than $30.00 (I paid $27.00 for mine...and yes..it has the hologram and is a true OEM unit). Don't worry about 802 g..long time before it is main stream and will provide improvement. matter of fact, the same ALFA with the different chipset for "n" is WORSE for b/g !
Quote:
Originally Posted by capt_douglas
It's been my experience that a high gain antenna and moderate power can give a considerable range boost, making connections more consistent.
|
Your absolutely right..and the MORE power with equal or BETTER sensitivity on the receiving end is even BETTER!
|
|
|
23-08-2010, 15:54
|
#530
|
Eternal Member
Join Date: May 2003
Location: Ft. Lauderdale, FL
Boat: Vancouver 36 cutter????
Posts: 620
|
@ArmyChief - it never ceases to amaze me that I'm a luddite when it comes to finding a great deal. Thanks for the link. The price is great and the 1W rating should do a better job of allowing me to connect a bit further offshore. Good info!
It appears that the USB will provide 500mA @5V or about 2.5W. Does anyone know if that's per port or total for all ports?
__________________
Capt. Douglas Abbott
USCG/MCA IV/M.I./C.I. 500-ton Oceans
|
|
|
23-08-2010, 16:34
|
#531
|
Marine Service Provider
Join Date: Jan 2010
Location: Toronto
Boat: Beneteau First 40
Posts: 78
|
That's per port max. Not all laptops will deliver that rate. You may also notice that your laptops battery depletion rate will increase.
__________________
Mike L
|
|
|
24-08-2010, 05:08
|
#532
|
Marine Service Provider
Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
|
Quote:
Originally Posted by mlahrkamp
That's per port max. Not all laptops will deliver that rate. You may also notice that your laptops battery depletion rate will increase.
|
The USB 2.0 Spec is 500mA at 5V per port. Correct. Also keep in mind that none of the WiFi systems (USB or Ethernet) on the market draw their max power output all the time (hardly ever in fact).
If you have an older laptop, it may only be USB 1.0, and not deliver that power level, but USB 2.0 has been in use since 2002, so there are not many 1.0 laptops around anymore. New laptops are now starting to appear with USB 3.0, which delivers 900mA at 5V per port.
Everything needs electricity, USB uses it from your laptop, Ethernet uses it from your boat. With USB, if you have a newer laptop, you can go hours and hours of using WiFi with no external power source with no issue.
When using Ethernet you may also notice that your boat's battery depletion rate will increase too.
The amount of electricity any of these devices uses is negligible, either to your laptop or your boat, so lets not discuss/argue about WiFi power draw. If you want to talk electricity, lets talk fridge systems.
Mark
|
|
|
24-08-2010, 05:22
|
#533
|
Registered User
Join Date: Jul 2010
Location: North Port, FL
Boat: Yamaha AR192
Posts: 297
|
Quote:
Originally Posted by kiltym
Everything needs electricity, USB uses it from your laptop, Ethernet uses it from your boat. With USB, if you have a newer laptop, you can go hours and hours of using WiFi with no external power source with no issue.
Mark
|
What I like about this statement. If you have no solar panels on your boat, yo ucan purchase something like this (cost and size to be determined by your needs and wallet)
Global Solar P3-62 Watt Folding Panel
Surf forever without using your boat resources. By the way, we use these in the military and they work great.
You could even buy a backpack, stick your laptop, long-range wifi, foldable solar panel assembly in teh pack and go ashore (public populated or that deserted island) and surf all day!
Doug
|
|
|
24-08-2010, 05:54
|
#534
|
Marine Service Provider
Join Date: Jan 2010
Location: Toronto
Boat: Beneteau First 40
Posts: 78
|
Power draw
Quote:
Originally Posted by kiltym
The amount any of these devices is negligible, being a commercial vendor Mike, you should know this.
|
Consider this:
Assuming 2.5W needed by a device.
At 5V that's 500mA. My laptop has a 4ah bat. If my laptop last for 2 hour normally, it would be reduced to about 96 minutes. That's a 20% impact.
At 12.5V that's 200mA. My boat carries 420ah so that is negligible. Solar panels and wind generator easily carry this. I can simply leave this on and connected all day.
__________________
Mike L
|
|
|
24-08-2010, 05:59
|
#535
|
Registered User
Join Date: Jul 2010
Location: North Port, FL
Boat: Yamaha AR192
Posts: 297
|
"My dog's bigger than your dog....."..LOL <G>
|
|
|
24-08-2010, 08:36
|
#536
|
Marine Service Provider
Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
|
Quote:
Originally Posted by mlahrkamp
Consider this:
Assuming 2.5W needed by a device.
At 5V that's 500mA. My laptop has a 4ah bat. If my laptop last for 2 hour normally, it would be reduced to about 96 minutes. That's a 20% impact.
At 12.5V that's 200mA. My boat carries 420ah so that is negligible. Solar panels and wind generator easily carry this. I can simply leave this on and connected all day.
|
Yes Mike, and, when I plug my netbook into my boats 12V system (via a 12V plug), and use the internet, I only consume the power needed by my computer and none for the WiFi system. You do agree it works this way too, right?
And to your statement also, you have the option to use no boat electricity with USB, but you don't have that option with Ethernet based systems. Exactly what I am doing right now as a matter of fact.
With an Ethernet based system, I have my computer on, and a draw on the internet system also, therefore using more electricity.
I'm done with this discussion. They all use electricity, and very little of it. We can go back and forth all day about this and its not getting anyone anywhere.
Mark
|
|
|
24-08-2010, 08:47
|
#537
|
Registered User
Join Date: Dec 2008
Location: NOT on Long Island - Look elsewhere! :-)
Boat: Beneteau 50
Posts: 451
|
Quote:
Originally Posted by captainmark55
|
Actually, the listing says it has 12db of gain:
23 DB GAIN from USB adapter
=
35 dB GAIN
You could have gotten an omni-directional 12db antenna that you'd never have to point. Just mount it up on the mast and forget about it. I have one that I haven't mounted yet -- I tested a 12db versus a 9 db antenna over the weekend, no write up yet, soon though. It was amazing hitting dozens of wifi signals.
Regards,
Brad
__________________
Email address is: b-cf "at" hallmont "dot" com
2000 Beneteau 505 "Summer Boost"
|
|
|
24-08-2010, 19:27
|
#538
|
Marine Service Provider
Join Date: Jan 2010
Location: Toronto
Boat: Beneteau First 40
Posts: 78
|
Quote:
Originally Posted by kiltym
Yes Mike, and, when I plug my netbook into my boats 12V system (via a 12V plug), and use the internet, I only consume the power needed by my computer and none for the WiFi system. You do agree it works this way too, right?
And to your statement also, you have the option to use no boat electricity with USB, but you don't have that option with Ethernet based systems. Exactly what I am doing right now as a matter of fact.
With an Ethernet based system, I have my computer on, and a draw on the internet system also, therefore using more electricity.
|
They do all use electricity, but drawing from the laptop will have to be replenished at some point. Are you suggesting that using power for a Wi-Fi device (whether external or internal) from your laptop is somehow free?
Your last sentence is wrong in that the amount of power being consumed by an ethernet based system would be the same or less (not more). This is because while a USB based external device or internal radio draws from the laptop battery, it ultimately comes from the recharging source (boat's 12V). This may require an inverter and a power brick (converter) with their associated inefficiencies. The Ubiquiti ethernet based devices can draw directly without the need for inverters/converters. And one could turn off the laptop's built in Wi-Fi thereby saving laptop battery power.
We each have what we consider is our own best (preferred) device (system). I am curious though how a USB based device would allow an iPhone, iPad or smartphone to connect since they do not have USB ports? The simple ethernet based solution is a wireless router that rebroadcasts the received Wi-Fi to them. Leaving an ethernet based system on all day with only a few mA draw provides instant access for iPhones, iPads, smartphones, crackberries, etc. or other newer portable devices that do not have traditional ports (USB or Ethernet).
__________________
Mike L
|
|
|
24-08-2010, 19:31
|
#539
|
Marine Service Provider
Join Date: Jan 2010
Location: Toronto
Boat: Beneteau First 40
Posts: 78
|
Quote:
Originally Posted by bene505
You could have gotten an omni-directional 12db antenna that you'd never have to point.
|
Hi Brad,
Out of curiosity, how big (tall) is your 12db antenna?
__________________
Mike L
|
|
|
25-08-2010, 04:42
|
#540
|
Marine Service Provider
Join Date: Oct 2009
Location: In the U.S.
Boat: FP Tobago 35 [sold]
Posts: 426
|
Quote:
Originally Posted by mlahrkamp
They do all use electricity, but drawing from the laptop will have to be replenished at some point. Are you suggesting that using power for a Wi-Fi device (whether external or internal) from your laptop is somehow free?
|
Basically free, yes. Perhaps the laptop is replenished off the boat, onshore? If not, the DC-DC 12V laptop adapters are pretty efficient (certainly much more than an inverter), and the amount of draw on a 12V system through a laptop, with, or without a USB WiFi device plugged in, is the same. Go ahead, try it yourself. Perhaps this is due to inefficiencies in the laptop charging/power systems, but you have to deal with this as its part of the laptop. The additional draw to a laptop (while plugged into an external power source) with a USB WiFi device plugged in is 0 (or so close it does not show up on my ammeter which goes to 100mA).
Quote:
Originally Posted by mlahrkamp
Your last sentence is wrong in that the amount of power being consumed by an ethernet based system would be the same or less (not more). This is because while a USB based external device or internal radio draws from the laptop battery, it ultimately comes from the recharging source (boat's 12V). This may require an inverter and a power brick (converter) with their associated inefficiencies. The Ubiquiti ethernet based devices can draw directly without the need for inverters/converters. And one could turn off the laptop's built in Wi-Fi thereby saving laptop battery power.
|
OK. I think we need to focus on one option or the other. Either the laptop is plugged into a 12V source, or its running off its own battery. Please do not try to merge the two concepts, they are different.
As I said above, if the computer is drawing off a 12V power source, please go ahead, plug in a USB device, turn off your WiFi card, do whatever you want. The draw will be the same. Its the way laptops are, for good or bad.
If its running off the laptop's battery, then there is no draw on the boat battery bank. Where and how this battery is recharged, may be on the boat, may be off the boat. But, when running off its own battery, its draw on the boat is 0.
If you are on a boat, and using a computer to be online, the draw with the USB adapter is less than Ethernet.
If you are on a boat, and using an iPhone to get online, the draw with a USB adapter is more than Ethernet as a computer will be on also (However, perhaps 2 people are online anyway, so its a wash). I would argue against leaving your product on all day long however, because if you want to discuss 300mA draws, I assume you would think that every little bit matters, and to be efficient on your boat, if your not using something, you turn it off.
I happen to spend more time on my computer than my iTouch, so for me, from a pure electricity standpoint, make out better with USB.
Agreed (probably not )? Can we please stop arguing about 300mA of power now?
Quote:
Originally Posted by mlahrkamp
We each have what we consider is our own best (preferred) device (system). I am curious though how a USB based device would allow an iPhone, iPad or smartphone to connect since they do not have USB ports?
|
The same way the product you sell does it Mike. Last I checked, iPhones, etc don't have Ethernet ports either.....
You set up a local access point. Your preferred method, and what you sell, is another piece of hardware, more wiring, and more management.
With USB, a software based Access Point can be set up on the computer where the USB WiFi device is attached, with no more wiring, no more electricity (assuming someone is using a computer anyway), and the best part, its FREE (I know us cruisers like that word lots ).
Mark
|
|
|
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Rate This Thread |
Linear Mode
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Advertise Here
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
Vendor Spotlight |
|
|
|
|
|