A4TECH WWT-13 Trackball
Trackball with 2 scroll wheels.
home page http://www.a4tech.com/product.asp?cid=1&scid=1&id=79
Dimension: 6.1″(L)* 3.9″(W)* 1.9″(H)
Not Optical Mechanism
This trackball is pretty bad. It is not optical (nor laser). You can tell it's not optical because you don't see a camera (LED) window in the ball socket. If you open the thing, you see that the ball rolls two bars, and the bars have slotted wheels attached. It works like 1990's mechanical mouse with a ball under. [see How Mouse Works]
2 bad reviews.
Someone is asking about these trackballs on reddit:
review by by zyxxiforr
I had the second [wwt-13] one. A long, loooong time ago. The shape was generally quite comfortable, but the whole experience was awful. The trackball is not optical, it's mechanooptical (like the old ball mice), it's resolution was rubbish, I had to rotate the ball several times to get the cursor across a screen, the rollers wold get dirty constantly, it required cleaning every hour or so, and the ball was too light and had no inertia.
Even for late 90's it wasn't a good device and it certainly isn't good now. So, unless it's a new model that just looks exactly the same as the old one, not recommended.
The first one looks like it's optical, but make sure before you buy. In my experience, most A4tech products were OK for their price. (I had several of their mice and keyboards back in the day)
I have had both.
The first i still have. it uses a mechanical tracking system like many older trackballs. This results in more friction, and for such a tiny ball, it doesnt get enough momentum to roll nicely on the rubber rollers. the wheels suck. they dont click, and they dont have a descrete haptic feedback when spun. the middle button requires lifting your hand off the ball to use. the main buttons feel flimsy. on the plus side, it is ambidextrous, and in spite of its flaws, is still usable.
The second, i got rid of asap. its got enough buttons, and two wheels is pretty nice, you can set one to horizontal scroll. but with the wheel orientation as a vertical wheel, it doesnt really make sense. also, the wheels are not "clicky" in that they cannot be pressed, and they dont provide a haptic feedback when spun, they spin freely and withoput resistance, so it is hard to control how fast you scroll. the button placement is horrible. you have to use your pinky to hit the side buttons, and the upper one requires you to lift your hand off the mouse to reach. The ball is too small, and feels bad. The tracking is mechanical.
see also Best Trackballs, Xah's Pick
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