My Portable "Desk" -- Version 2
Why?
While my handtop does very nicely for highly mobile applications, I also use it as my primary computing device. To that end I have my docking station set up in my home office with connections to wired ethernet, a large monitor, and a Bluetooth "connected" keyboard and mouse. However, there are also times when I want something like this setup in a remote location. Tearing it all down and then setting it all up again takes way too much time. That was the reason I created "My Portable 'Desk' -- Version 1."
However, that version was A/C powered only. I wanted something I could conceivably use in a car or plane and maybe even under it's own power. That's what prompted me to create Version 2, which you'll see below.
I still haven't found a way to squeeze all this into a laptop-sized device, but this generation gets a lot closer to that ideal.
Version 2 :
While I wanted a solution that would be more power-versitile, I did not want to go through a lot of "surgery," especially on relatively expensive items, in order to achieve it. For that reason, I decided not to open the UX docking cradle and use just the innards. That meant I needed something deep enough to accomodate the UX docking cradle. In addition it had to be wide enough to accomodate a workable keyboard and whatever display unit I chose. To keep the width down, I went with an 8.4 inch display unit and a USB keyboard (which is actually for the Samsung Q1). That allowed me to use a Pelican 1400 case as the enclosure.
The Pelican 1400 case is a rugged, water-tight case that is more commonly used for transporting cameras and accessories into environments where they might be damaged in a lesser container. It is fairly easy to buy locally by searching camera shops and electronics stores at least in the yellow and black varieties. If you order on-line, you can get a variety of designer colors. The case comes with foam inserts that work very well for shock-protecting equipment that is not in use, but also doesn't allow air flow for equipment that is. I kept the foam for protecting the contents during travel, but pull it out when the unit is in use.
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In addition to being rugged and water-tight for worry free toting, the case also sports two reinforced hole sets that will take a standard padlock or key lock. With the lock in place, the case cannot be opened without resorting to major industrial tools. With the addition of a titanium security strap (available at most large hardware stores and bicycle shops) you can lock the case to your hotel room bed-frame. Before you leave the room, you can lock the case onto the security strap and slide the case under the bed. Even if some less-than-reputable help discovers the case, they'll quickly discover that they can't make off with it. or its contents.
Another bonus of using the Pelican case is that the hinges require pressure to rotate. This allows me to set the top of the case, containing the screen at a perfect readable angle without any additonal hardware.
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The monitor, mounted on the lid is an 8.4 inch "flush mount" SVGA monitor that I ordered on-line from LCDTFT.com. This monitor is designed for use in cars and planes so it runs on 12volts DC. That was an important consideration in allowing me to streamline the power requirements for the whole assembly. (More on this in a moment.)
I also chose this monitor because it has an 800x600 pixel native resolution, rather than only 800x480. It also supports much greater resolution by "interpolating." I have used the screen in a virtual 1600x1200 resolution and found it very readable. The monitor is nearly double the size of the built-in monitor on the UX which fairly well eliminates the need for squinting to read very small text.
I used "Industrial Strength" Velcro® to mount all of the components onto the case. The main reason for using Velcro® instead of more permanent solutions was that I want to be able to remove my cradle for use elsewhere and I may want to re-use the monitor and other components (perhaps in my Portable Desk - Version 3 :) ) The cables are kept in place by some 3M self-sticking "wire keepers" that you can find at most hardware stores.
I did violate my "no surgery" rule at one point here. The monitor that I used has one cable for VGA in and another cable that contains the wires for power and two composite video inputs. Since I didn't need the additional composite inputs, I clipped off the end of the cable and stored the composite wires in case I do want them in the future. That left the power input wires which required 12 volts at about 1 amp. This is where things get really interesting.
I already owned an APC Universal Power Adapter, which I had bought for use with my UX because it runs off of AC (wall) power and DC (car and airplane) power. The folks at APC added a useful feature to their UPA: It also has a USB power-only jack that will allow you to charge devices that can be recharged with a USB cable. This USB power jack puts out 5 volts at a whopping 2 amps. Turning back to my electricity/electronics education, I remembered that you can use a DC-to-DC power converter to increase voltage at a cost in amperage. (Essentially power (volts x amps, or watts) remains constant.) So 5 volts at 2 amps can be converted to 12v at 833 milli-amps. Was it close enough? A quick call to tech support confirmed that the monitor would run on 750 mA.
Now I had to get a reliable DC-to-DC converter that could handle 2 amps input. I could find only one choice, at anywhere near a reasonable price; Dimension Engineering's AnyVolt, which I ordered from RobotShop.com. The AnyVolt will take any voltage from 4.2 to 28 volts and step it up or down to any voltage from 2.5 to 24 volts, using a small adjustment knob. It has a display that shows the output volts, accurate to one decimal place so you can be sure you're supplying the right voltage. It also has built-in current limiting so you won't accidentally fry your monitor. It even has nice screw terminals for attaching the power wires. It was also half the price of the nearest competition which didn't have all those nice features. The other small bit of surgery was to cut apart a USB cable I had lying around, isolate the two power lines from the cable and attach them to the input side of the AnyVolt. I plugged the USB cable into the USB power jack on the APC power adapter and set the output voltage of the AnyVolt to 12 volts. Then I attached the power wires from the monitor to the AnyVolt output and was gratified to see the monitor power on exactly as it should.
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You can see a patch of Velcro® in the picture above which is used to hold the UX cradle in place in the base. There were two additional pieces I needed to make it all work. The first was a "right angle" adapter for the VGA port on the cradle. The reason for needing this was that standard VGA cables have very long connectors. Without the right-angle adapter, the connector forced the cradle too far forward.
The other additional piece was a VGA "gender changer." This was needed because the short VGA cable from the monitor was long enough to reach the cradle, but it had a female connector, designed to connect to the male end of a standard VGA cable. I didn't see the need to take up extra space with even the shortest VGA cable, so I used a male-to-male VGA gender changer to mate the monitor cable to the cradle.
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You may also want to purchase right-angle or any-angle USB adapters for the USB ports in the rear of the cradle although I've found that there is generally enough clearance for most USB connectors. The Ethernet (wired network) connectors and Firewire connectors are even smaller and have more than enough clearance.
That covers all the preliminaries. Now lets look at the finished product:
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As you can see, there is a fair bit of space still left in the case. I use the extra space to hold a couple of small "tackle" containers (which, naturally, are Velcro-ed to the sides so they don't bump around in transit). You can get these at nearly any hardware store and most stores that carry camping or fishing supplies. You could also use some of that extra space to install a thin format DVD drive with a short USB connector to the cradle. Keep in mind that DVD burners will probably require an additional power supply.
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What's Next
There are only two things left that I might be able to do to make the "Portable Office" even more portable: First, I could make the whole unit smaller, closer to a laptop in size, but still without disecting the cradle. This would prevent you from being able to carry the UX inside the assembly while in transit, but you normally would be carrying it on your person anyway. Second, I could find a way to place rechargeable battery power in-between the power adapter and the computer/monitor. Then I'd have a unit that could be used for some time without the need for an AC or DC power supply. This battery would need to supply around 4 to 6 amps over several hours to be useful. At the moment, I'm fairly happy with what I have. I use the extra room in the case to carry additional odds and ends like USB cables and other adapters and I hardly ever miss using the larger display when I'm nowhere near a power supply. I probably won't pursue a version 3 unless either of those conditions change.
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