A question about wifi antenna and software for an iPad was raised by Harry Morel. Jim Hamm got right on it, and he passes along the information to us.
"I use the Wi-Fire antenna occasionally on my Mac when I'm traveling and the wifi signal is weak. It helps to boost or capture more of the signal so your Mac can access the internet. And yes, your Mac will have a built-in wifi card to pick up the signal.
"You can do a Google search on how to turn on internet sharing on a Mac. Here's one link to look at. Here's another one. As I understand it the Mac must be connected to the internet by ethernet, then it can share its connection via wifi to another device, such as another Mac or the iPad.
"I've not used this internet sharing concept, so I won't be covering it in my iPad presentation. Perhaps someone else on this email distribution list might have some suggestions on internet sharing on a Mac.
"Here's another option to consider if you're traveling: if your iPad has 3G capability, and you're in a 3G area (not Prescott), and you don't have wifi available, and you're willing to spend $25, you can buy 3G from your carrier for a month. Then you can turn it off at the end of the month so you won't be billed another $25. The minimum time period is one month. Not the most desirable option, but if you need to have an internet connection while you're away from home, this is available.
"If you're talking about wifi in your house and your iPad won't connect to the signal, perhaps the signal is weak. You can check the signal strength by holding the option key on your Mac and clicking the wifi icon to see what the RSSI is. Down below is a meter to help you understand the results. If your signal is very weak, then you need to boost it.
"Here is another diagnostic tool to check both the wifi signal strength and noise level. If your wifi signal is good in your house and the noise level low, and your iPad won't connect to it, then perhaps there is something wrong with the iPad. It is covered by a one-year warranty from Apple, so a visit to an Apple store might be in order," and as always, Jim signs off with a grin. (Click to enlarge the screen shot.)
Will Li-Fi Take Over for Wi-Fi?
Fascinating conjecture here: Li-Fi might replace Wi-Fi. Jim Hamm located this site. A researcher says "There are around 14 billion light bulbs worldwide, they just need to be replaced with LED ones that transmit data." Jim comments, "An interesting concept."
Measure a WiFi Signal
Jim Hamm passes along some helpful info: "If, say, you're traveling with a Mac laptop and it shows it's receiving a WiFi signal, but you're unable to connect to the internet, what to do?
The first thing I do is check to see how strong is the WiFi signal I'm receiving. Hold the option key down and then click the WiFi icon. You will see a variety of data, including RSSI (Received Signal Strength Indication). What does this mean? Take a look at the following meter to get an idea: (Click to enlarge.)
Green is good, yellow is marginal in the above meter. The minuses reflect a loss or reduction in power. If I remember correctly, the meeting room at the Prescott Library, where we hold the PMUG meetings, has an RSSI of about a -70 and we usually can connect okay. As I'm typing this I'm close to the router and my RSSI is a -40. In my experience, if you show an RSSI of around -80 you probably won't be able to connect to the internet.
In addition to strength, another important element of a WiFi signal is the amount of noise (interference from microwave, cell phones, etc) present. If you're showing a good WiFi signal but are having difficulty connecting, or staying connected, to the internet, then possibly you've got noise interference. A spread of 15-20 dBm is desirable. For example, say the strength is -60 and the noise is -80, you're in good shape.
What can you do to improve RSSI? Move closer to the base station or router; walk around and change the location of your computer -- maybe you'll move from behind an obstruction; buy a WiFi booster. I've used several, and they do help.
I've got some friends that recently converted to a Mac and I thought this might be helpful for them. The same concept applies to PC users, but I don't recall (if I ever knew) how to measure RSSI on a PC."
WiFi Hotspots in Prescott
This list of WiFi hotspots in Prescott comes to us from David Passell. Double click on the screen shot to enlarge it.
Allen Laudenslager adds to this list Rooster's Cafe, across from Think4Ink on Montezuma. He says, "Free WiFi, great coffee, good food and outdoor seating if you prefer. Besides, all the people are just nice folks."
What Happens on WiFi & the Internet
"Interesting to read what can -- and seemingly does -- happen on WiFi and the Internet these days," Jim Hamm comments. "Two thoughts on the following article: first, people using unencrypted WiFi are just putting themselves at risk. Not too smart. Second, I find it hard to believe Google -- or any other enterprise, for that matter -- would put a program out on the street and not test, or know, what it was doing or capturing.
"Google said: 'Google's intention was only to record the identity and position of Wi-Fi hotspots in order to power a location service it operates, the company said. However, the software it used to record that information went much further, intercepting and storing data packets, too.'
"Now, I ask you, why didn't Google know that beforehand?" ... Jim
Make Your Own WiFi Hotspot
Here's a short video from CNET on how to turn your Mac or PC into a WiFi hotspot. Jim Hamm explains, "This can be useful if, say, you're traveling and in a hotel room with one ethernet connection and two computers. Instead of arguing as to who gets the ethernet first, just remember this tip. This has happened several times to Zee and I (not the arguing, just the circumstance. She gets the ethernet first...
"I also wonder if this wouldn't be a convenient way to transfer documents from one computer to another? For example, I occasionally want to move a document--say, an email or picture--from one of my Macs to the other. What I've been doing is just emailing it to myself. I don't subscribe to MobileMe, and I haven't tried Google Docs or DropBox yet either. This just might work."