Tuesday, December 24, 2013

Fastest USB Flashdrive

Well, I don't know if this is the fastest flash drive on the market right now, but from all the reviews I have read, it was consensus that the fastest thumbdrive you can buy right now is this Sandisk Extreme 64GB. I bought one and personally can tell you that this thing can read and write data much faster than all of my existing flash drives that have the USB2 interface. The Sandisk Extreme 64GB is at least 3 times faster with write speed of 80MB/sec and read of a whopping 135MB/sec. Of course, I plugged this drive into a USB3 port on a PCIe adapter card on my 5 year-old PC running Windows 8 64bit. USB-based data transfers can consume a lot of CPU cycles so you may not get these transfer speeds if your computer has a slower CPU. Incidentally, I use the copying of a 5GB file as a test. If you copy multiple smaller files, the average speed is undoubtedly slower, but I assume it is still faster then the USB2 drives.

You can grab one from Amazon here. I assume the 190 MB/s advertised rate on Amazon site is based on a test on a machine with beefier specs than mine.

http://tinyurl.com/m2nvjor

Monday, December 23, 2013

Free Way to Scan to PDF from Scanner


If you need to scan some paper documents and save the resulting files as PDFs without doing any more fancy post scan processing, then the best way I have found that is free is a combination of an image editing program and a "save-to-PDF" plug-in for it.

All versions of the Microsoft Windows come with a very barebone graphics manipulation program called Paint. If you find it too simplistic such as its inability to do layers or certain filters like Photoshop, then Paint.NET is for you. It's a small program by itself, but it needs Microsoft .NET Framework to run, so for those who do not like to have to install the framework, then they have to look elsewhere. Below is the official hardware and software requirements for Paint.NET.

http://www.getpaint.net

Minimum Requirements

Windows 7 (recommended), Windows Vista,  or Windows XP (SP2 or later)
.NET Framework 3.5 SP1
800MHz processor
512MB of RAM
1024 x 768 screen resolution
200+ MB hard drive space

I ran it on Windows 8 64bit, and it runs fine.

Moreover, if your goal is to tell Paint.NET to acquire an image from a scanner and then save the scanned image as a PDF, you need to get an plug-in for this program. It is called Im(age)PDF filetype.

You can download it here:
http://www.comsquare.ch/files/downloads/ImPDF.FileType%20v1.3.zip

Installing the plug-in is very simple. You would extract the zip folder and copy the two files "ImPDF.FileType.dll" and "ImPDF.Command.exe" into the "FileTypes" folder of your Paint.NET installation.  A typical location is "C:\Program Files\Paint.NET\FileTypes". When you launch Paint.NET after this, you will find an extra option under the Save As command. The rest of the process is pretty much self explanatory.

You can find more information about this plug-in at the Paint.NET forum where the author of the program is willing to take suggestions for improving the plug-in.
http://forums.getpaint.net/index.php?/topic/22863-imagepdf-filetype-plugin/

Tuesday, December 17, 2013

Actiontec MOCA : A Products Guide

I am a great fan of MOCA, the networking technology standard that uses the home's coax grid to carry network and Internet signal. Coax is the cable type that carries your cable TV. After being disappointed with the HomePlug technology that does the same using the home's electrical wiring grid, I am glad there is MOCA. I have yet encountered a major issue with MOCA with the exception of one time when it interferes with DVR. Given that most homes in the urban areas have cable TV, or at least coax cables running in the walls, the homes are ready for MOCA. All you need is the appropriate MOCA devices.

The MOCA specification is now version 2, ratified over 2 years ago. Yet, I have not seen any MOCA products certified for it. I am not sure what is the hold up. Amazingly given how well MOCA works, there are only few manufacturers of MOCA devices. Actiontec and D-Link are the only ones I know of. I do not use D-Link stuff because devices from Actiontec have worked so well.

You can setup an Actiontec MOCA relay using these various devices. Because you would need at least 2 MOCA devices to start, the best and cheapest way to get things going is getting this Actiontec Ethernet to Coax Adapter Kit ECB2500CK01 which consists of a pair of identical ECB2500C devices. If you need a third device, then you would just get one more device. Again, as a lone device, it's called ECB2500C.


This is what I use when I already have a router on hand. This ECB2500CK01 kit only acts as a relay of the signal within the coax wiring. They do not have routing, DHCP, nor wifi capability. They basically act like a glorified network cable. You can setup encryption on these devices so the data transmitted between them are encrypted in case someone with other MOCA devices within the same coax grid eavesdrops on the signal even by accident. Inter-devices encryption is done with a Windows utility that can be downloaded from the Actiontec website.

The ECB2500C only has 1 network jack, so if you want additional jacks, you would use one of these (click on the image for bigger view):

Actiontec ECB3500T Ethernet over Coax Network Adapter. Basically, the ECB3500T acts like an ECB2500C, but it has 3 additional network ports. I am not clear on whether the ports are gigabit or not. The ECB2500C's lone network port maxes out at 100mbps.
http://www.actiontec.com/products/datasheets/Trika_ECB3500T_DATASHEET.pdf

At this writing, Amazon also sells model ECB3500T01. I think this is the same as ECB3500T.

So what if you want the functionality of the ECB3500T, but with wifi included. Then you would get this:


WCB3000NK01 or WCB3000N (click on the image for bigger view)
The WCB3000NK01 is a kit that consists of an ECB2500C and a WCB3000N. The WCB3000N is basically a MOCA wireless access point.

http://www.actiontec.com/products/datasheets/wcb3000ndatasheet_finalwb.pdf

Below is a link to a review of another MOCA device made by Netgear. It's an old review on a product that seems to have been discontinued. As said, I am puzzled as to why this technology has not become popular.

http://tinyurl.com/netgear-moca-review

Further reading by someone who wrote a detailed piece on his experience with MOCA can be found here:
http://forums.anandtech.com/showthread.php?t=2239404






Sunday, December 15, 2013

Installing Windows 7 Without a DVD Drive.

I recently had to install Windows XP on an old Dell desktop. For some weird reason, even with different Windows XP CDs, while XP was installed fine, it could not get Windows updates. It was running IE 8 with Service Pack 3. As such, it should be up-to-date enough for Microsoft Windows Update to work, but it stubbornly would not. The Internet connection is fine. I even install .Net Framework 2 as recommended by some of the troubleshooting sites.

I finally gave up and decided to risk it with Windows 7 32bit. The problem was the computer does not have a DVD drive to run the Windows 7 installation DVD. I had a USB external DVD drive but the machine could not boot from an external optical drive. However, XP can read from it. Using this connection, I copied over all of the installation files from the Windows 7 DVD onto a second partition on the harddrive and simply run the installer file. It worked. The Dell now has Windows 7. Windows 7 offered me to do an upgrade from XP, but I told it start from scratch. It installed a fresh copy of Windows 7, saving the old files including XP itself, in a folder called Windows.old. I used Windows 7 built-in Disk Cleanup to remove this Windows.old folder.

The point of this experience is you do not need to install Windows 7 directly from the DVD disc. Yes, Windows 7 can do Windows Update just fine.

Saturday, December 14, 2013

Wifi Connection Is A Two-Way Communication


As more and more people have portable wireless devices like smart phones, tablets, and laptops, accessing to online information no longer is restricted to one or a few locations in the homes or offices where their bulky desktops are located. They would be in the breakroom and can check on the latest sport scores on their phones. They can be sitting on the toilet and not miss the latest text or email message. (Admit it, you have done that).

The problem is there might not be a reliable signal in these places. When setting up a wireless data network, people do not usually think about getting the wifi signal in the breakroom or bathroom. Therefore, they would initially install access points, also known as APs, that transmit the wifi signal that is reachable to only the "important" places. When they are in other locations however, they cannot seem to get Internet access via the wifi even when the devices say there is signal detected, even with a strong one. Here is why.

Wifi is a two-way communication. That is, the two devices on both ends of the connection must be able to reliably communicate with each other to maintain the connection. If the AP does not get a constant I-am-still-here feedback from the portable device, the AP assumes that the device no longer needs to associate with it. The AP will then break off the connection.

If your device's signal cannot reach the AP to maintain this association, the AP is useless. Therefore you need to place multiple APs in your location so the closest AP in the chain can relay the signal from your devices back to the gateway router which is the entry point for the incoming Internet. While there is some signal loss of the original signal from your portable devices when it finally reaches the gateway router, this incoming signal is still much better than if the portable device is transmitting the signal to the gateway router directly. A gateway router can also act as an AP. If it does, then it is the most upstream AP in the chain.

You can buy high-gain APs to increase wireless reception. Yes, they work well at pumping out stronger signal to the portable devices. However, using these high gain APs gives the illusion of better signal because as stated, if the AP does not get the acknowledgement signal from the devices, the association is lost. This is like listening to music on your car radio. The massive radio tower would push the music to your car, but your car radio does not need tell the radio tower what music to broadcast. Listening to the radio is a one-way mode of wireless communication. By contrast, with wifi, the portable devices need to transmit their signal to the APs requesting information such as Internet websites.

In short, do not buy into the hype from wifi AP makers about their high gain APs. You need to understand how wireless technology works in this context so you can buy and setup the right devices to get reliable wifi signal in the dead spots in the home or office.