Aug 27, 2014

Aug - 13 2014 | By

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Both Glenn & Paul were in the studio for today's show

Podcasts of recent Zentech shows are here.


Glenn thanked those who've become contributing members of KVMR. If you'd like to become a member, please visit KVMR.

Paul mentioned that he bought a 31-bit driver kit for $11. It "contains every possible tiny, miniscule, peculiar undoing screw type bits". <More about screw heads below>

In the past couple of years, MacBook Air models have been coming out with Solid State Drives (SSD). Apple made a proprietary format that's about twice the length of a chewing gum stick with about 15 to 20 gold pins on the end, in a PCI Express format. The back of the MacBook Air has a slot that takes a 128 or 256 gig SSD. So, the drive can be replaced though they cost more per gig than traditional drives.

But there have been problems with the SSD in the early MacBook Air models — they become unreliable and Apple has issued a recall. "If you have weird things going on with your MacBook Air" do a search for the words: MacBook Air recall. With no moving parts, SSDs are extremely reliable, but when they go wrong, they go seriously wrong and with no warning.

The electronics on these drives tries to evenly distribute usage over the entire drive so no single area gets written to more than other areas. The memory in the drives can be written to a limited number of times — 20,000 times, Paul thought — before they go bad. He thought that would be about 10 years of typical usage. Cosmic radiation wares out silicon chips and solid state devices, he added. This was discovered at the beginning of the space age when crafts were sent into space where radiation is more intense.

Paul asked Glenn about his "green finger lights". Glenn said he got them at either Ebay or Amazon around the July 4th. They're composed of LED lights, which are actually very bright, Glenn said.

Paul talked about the safety of laser pointers. People have ended up in the hospital after shining them in their eyes. The red lasers are not as dangerous as people once thought but there are now high intensity blue & white LEDs. Though their wattage may not be especially high, their beams tend to be concentrated in one direction. Paul couldn't see for a couple of hours after looking at one that was only 5 watts. Adding to the problem is the lack of warnings on many models.

Paul went on to say LED lights use less energy for the light they put out than compact fluorescent because less energy ends up as heat. They last longer — 50,000 to 100,000 hours. And the spectrum is more pleasing.

He related a story about the highways department in Alaska replacing high-pressure mercury street lamps between Fairbanks and Anchorage with LED lamps. They had a problem when winter came and the LED lamps froze over. Unlike mercury & sodium lamps, which generate some heat, the LED lamps run too cool to keep the ice off. Heaters had to be added.

Glenn said that the city of Davis is replacing their lights with LEDs in a test area and asking people for their opinions. Some people don't like them because they're too bright and interfere with sleep.

Glenn mentioned a friend with an iPhone 5S with a power button that was intermittent. They found out this is a known problem with some iPhones. He didn't know if a recall has been issued. If yours is under warranty or you have Apple Care, Apple will replace or repair it for free. If it's not under warranty, try begging & pleading with Apple; there's fair chance they'll repair it for free — after all, it's their problem. Paul suggested doing a search with the words: iPhone 5S power button recall.

Paul said there is technology to block cell phone signals during public performances and in movie theaters. It works by sending out a transmission at the frequencies the phone use — a jamming signal. It doesn't harm the cell phone. The phone still shows it has reception but it won't ring. Blocking is not commonly done because of possible legal liability — as in the case of doctor needing to receive an emergency call.

Glenn got a new vehicle recently, a 2012 Prius C. It's the smallest in the Prius line. It's very basic — no power seats, windows and doors. He found that it will happily accept his 64gig flash drive whereas the 2010 model will not. He speculated that the 2010 model could only take up to 32gig memory.

Paul talked about regenerative braking in electric cars. The electric motor also acts as generator when going downhill or applying brakes. The energy derived from slowing the vehicle is used to charge the batteries.

There is a hacker community for hybrid cars, Paul said. Some hybrid cars aren't supposed to be charged from house current. <The gas engine of the car runs a generator to charge the batteries, as I recall> If I understood Paul correctly, the generator only charges the batteries up to 2/3 full. The hackers look for ways to fully charge the batteries using household current.

Earlier, Glenn searched for hacking tips for his Prius and didn't find much. The one interesting thing he found was making the car go up to 45mph in electric-only mode (not using the gas engine). Normally one can go only so fast before the engine will "decide" to kick in. Glenn would like to remain in electric-only mode at his discretion.

Glenn said the Prius C gets the best mileage of Prius models. He got 46 mpg on his 1st tank of gas and 48 mpg on the second full tank. He found the onboard electronics kept track of the mileage very accurately and he'll no longer need to keep written records and manually calculating the mileage.

Paul gave the algorithm to calculate the mileage. Every time you fill up with gas you reset the odometer (or write down the miles). Then if you go 100 miles and you fill up again, the number of gallons you put in corresponds that 100 miles. Then divide 100 by the number of the gallons. Keeping track of your mileage can give an indication of engine problems. If the mileage suddenly goes down, there may be a problem.

Steve called. He had sent the guys some screen shots of the messages he's getting on his computer. He has a wireless connection at home. When he goes to a website he gets the message "Can't display that page. Do you want to fix the problem?". When he clicks "yes" and closes the troubleshooter it goes to the desired website. <I guess the problem is that it keeps happening.>
– Try a different browser like Firefox or Chrome.
– Steve thought it might be because TV uses the internet connection too and there might not be enough bandwidth. Paul said it may slow things down but shouldn't keep a website from loading.
– The machine may be losing connection to the internet and the problem is not with the browser. When he clicked "fix the problem" the machine then connected to the internet.
– Try other machines or wireless devices simultaneously.
– Try SpeedTest. There are apps called SpeedTest for both the Android & iPhone.
– Unplug everything. That includes the computer. Shut down the computer first, then unplug the computer, unplug everything that uses the internet, wait 2 minutes. Then reverse the order — turn on the internet and, finally, the computer.

Steve also asked if this show will be podcast. Glenn said he won't have a chance to do that until next week. <When available, it will be here>

Paul emphasized the value of screen shots for trouble shooting. If there isn't an easy way to do it on the device itself, take a picture of the screen with a camera. The PC has the print screen button ("prt scr" on my keyboard) which takes the image of the screen and puts it in the clipboard (as if you did a 'cut' in a cut-and-paste operation). You then run a graphics program like Paint or even Microsoft Word and paste it in (control + V).

Paul offered a tip for zooming in & out when using Firefox & some other browsers. You can zoom by holding down the Control key and working the scroll wheel on the mouse.

Paul was working on 2 MacBook Airs — one from 2010 & the other from 2012. He was trying to remove the back panel to get at the battery — the Macs don't have a removable battery. He was having a problem getting the screws out and decided to google: macbook air floor panel. He found that in 2010 Apple started using a never-seen-before screw head called a pentalobe. It took a while but the Chinese are now producing the pentalobe driver.
<Wikipedia: screw types>

John from Citrus Heights called. He's a student at American River College in the area of design technology. The school's website is set up to work best with the Firefox browser. He also uses Google Docs & Gmail, which is best accessed with Chrome, he claims. At work he uses Outlook.
– Paul thinks that Internet Explorer should only be used as a last resort and shouldn't be used at all by those still using Windows XP. IE has a long history of being unpatched in a timely manner.
– Glenn has been using Firefox for Google Docs with success. He's tried Chrome but doesn't like the interface, probably because he's not used to it.
– Paul likes Chrome but he's concerned that Google gathers info about you when you use it.

Finally, Paul mentioned the latest in car radios. You can get a more than adequate car stereo for about $25. It has no moving parts — no CD or cassette player. You can plug a USB music player into it. It has an auxiliary port if you want to plug in an iPod. It has Bluetooth & an AM/FM radio. Besides the power button, all controls are thru the touch screen

Last update 11:07 PM 8/27/2014

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