Posts from — May 2012
As I’ve mentioned before, I’m planning on getting a keyboard with mechanical Cherry keys.Â I had a challenge: how to figure out color to get?Â For example, the Leopard keyboard is available with Brown, Blue, Black, Red, Clear, or White keys.Â (The Cherry color refers to the stem color, as you can see above, which indicates the feel of the key.)
Since I don’t feel like ordering and returning a whole bunch of keyboards, I added the readily available colors to my most recent connector order; Mouser and Digikey sell the individual switches for $1.00-$1.50.
Even without a key cap, I can tell my order of preference:
- It’s Blue for me.Â I really love the feel of the blue button; it has a great tactile break-over feel, with a satisfying but not too loud click.
- The White is OK; it has some break-over, and is quieter than the blue.
- I’ll pass on the Black for typing; it has a linear response, and just feels “blah” for typing.
So now I’m comfortable with a choice of Cherry Blues, for less than the cost of returning a keyboard.
Update 7/2/2012: when I wrote this, I couldn’t find the geekhack.org Cherry key switch guide.Â Apparently, it’s gone, butÂ Overclock.net has some good info on mechanical keyboards, including the various flavors of Cherry switches.
May 31, 2012 No Comments
OK, it’s not some fancy collectable Parker pen – if I ever own a collectible pen it’ll be by accident.Â Instead it’s a classic but not too fancy Parker Jotter body with a Retro 1951 refill.
I’ve had this Parker pen for a long time — probably since high school, way back when Parker was actually cool and innovative (OK, I’m dating myself….).Â It’s still a nice, classic, functional, but not flashy pen body.
The Retro 1951 refill is actually a Schmidt EasyFlow 9000; Retro 1951 simply had the best deal on Amazon.Â I’ve been wanting to try the EasyFlow 9000 for a while, but don’t care for the style or price of the Retro 1951 pens.Â Solution?Â I tacked on a set of refills to my latest Amazon order.
The EasyFlow is good; it’s much better than a standard ballpoint refill, but won’t make me give up gel pens.Â I’d say it’s close to the feel and performance of a Uni Jetstream or Zebra Surari, but not quite as good.Â The line is thicker, and based on my initial use, there is more globbing.
However, I’m still happy with the combination; it’s a great pocket pen: rugged metal body with a smooth writing, write-anywhere refill.
7/2/2012 Notes: this classic all-metal Jotter is still sold today, and still looks great.Â However, I don’t find the grip comfortable for sustained writing — theÂ barrel is too small and smooth.
May 29, 2012 No Comments
I’ve been using my G-Blanc frequently, partly out of necessity. The G-Blanc is a Pilot G-2 body (a charcoal G-2 Limited Edition in my case) with a chopped Mont Blanc roller ball refill.
I really like the G-2 Limited Edition body: it’s reasonably priced for a metal pen (~$10), with a comfortable grip, cool colors, and a nice metallic feel. In fact, I’ll probably pick up another in a month or two.
Although I love micro tip gel pens, I’ve come to appreciate a good roller ball refill.Â The Fine Mont Blanc refill is not fine by my standards, but it’s fine enough, and does have a great feel – smooth and flowing, but controlled.Â I’ve noticed the line width does vary substantially with the paper type; the line is considerably narrower on Rhodia paper.
The Mont Blanc refill does have a big problem: it dries out quickly.Â If I don’t use it for a while, it does not write well at well, with very spotty ink flow.Â After quite a bit of use, I’ve been able to get it back to good flow — and have been using it often since then so I won’t have to repeat this exercise.
This is a big problem for me, since I like to switch pens around (I’m trying to evaluate all the pens I’ve bought in the last couple of years), and don’t spend most of my time writing.Â I think I’ll try taking the refill out and capping it when I don’t plan on using the Mont Blanc refill for a while.
Since a standard 4 3/8″ roller ball fits in the G-2 Limited, I’ve been trying out a fine blue German made bluRAFIA refill (similar to the Schmidt 888) in the G-2.Â Compared to the Mont Blanc, it’s a lot cheaper, and a little wetter, with a wider line, and a longer drying time.Â It also globs more.Â Still, overall the blueRAFIA is good overall.Â The Mont Blanc definitely writes better, but especially with the drying problem, I’m not sure I’ll buy another.
Side note: a chopped Mont Blanc refill should fit in many roller pens, basically anywhere a Schmidt 888 fits.
Update 7/2/2012: it’s a lot of fun to play with compatible refills.Â I currently have 3 G2 Limiteds (Charcoal, Champagne, and Blue) fitted with bluRAFIA blue fine, Uniball Signo 0.5mm blue gel , and G-2 0.7mm or Mont Blanc refills.Â The Signo and bluRAFIA refills fit without any hacking.
May 24, 2012 No Comments
I’ve been going through my eclectic electric motor collection, and I’ve had a lot of problems finding accurate information on many of the motors. Â I love manufacturers that still provide datasheets for out of production products, especially when they make it easy to find.
My Electro-Craft E-3618-E-F00AN motors are a great example; even using my best google-fu I couldn’t find any data online, just people trying to sell them or repair them.Â I finally hit paydirt when I went looking for, and found, an old paper Electro-Craft catalog from 1993.Â Sometimes having packrats around is good….
May 8, 2012 1 Comment
Although I use commercial motion control equipment, I enjoy learning about the fundamentals of servo motor control.Â I’m currently going through the posts in TI’s Motor Control blog; they have a high signal to marketing ratio, and include a lot of non-obvious tips, like the best time to measure current.
The posts include a number of simulations which are helpful in understanding the different control topologies.Â However, there is still no substitute for spinning actual motors.
Commercial controllers are great at getting you up and running quickly, but don’t let you play with different control techniques.Â For learning, motion control development kits are the way to go.
My dev kit is TI’s DRV8312-C2 kit with a F28035 DSP, DRV8312 brushless DC driver chip, and servo motor (unfortunately TI didn’t include a dual shaft model, but I have plenty of servo motors with encoders).Â TI’s ControlSuite software provides a variety of control methods.
May 3, 2012 No Comments
At the Design West 2012 / Embedded Systems Conference I had the opportunity to try out a unique technology: Microchip Technology’s mTouch metal over cap buttons.Â This technology provides the capability to fairly easily create affordable custom non-contact metal buttons.
Since this technology uses capacitive sensing, the buttons are non-contact and should have a long life.Â However, they’re still very short stroke and thus provide very little mechanical feedback.Â Microchip’s demo used LED point lights to provide feedback.Â Microchip’s demo kit currently isn’t available for sale, but they said it was coming sometime, probably for less than $100.
You could use this technology to make ESD-safe buttons.Â However, since the metal needs to bend a bit, it won’t be as rugged as the more expensive anti-vandal buttons.
I’ll probably buy the demo kit when it comes out, because it’s a cool gadget…
May 1, 2012 No Comments