12/17/12

XT Racing GPX Pro Review

Note, this is a review of the first generation GPX Pro, not the current GPX Pro4/8 units- however, much of this review should apply to both units.

Overall, I’m in love with the GPX Pro- it’s a great cost effective solution for capturing and analyzing data while you are driving or riding (all my tests were done on my SV650 race bike). The unit is easy to install, use and surprisingly easy to read, even in strong sunlight- probably due to it’s use of a grey-scale LCD display rather then a color display that is used on laptops and iPads. The software “GPX Studio”, is also easy to use and has tons of great information, but unfortunately Windows only (no plans on a OSX or Linux port, but it works great under VMWare/Parallels). I really learn a lot by looking at my brake markers and corner speed.
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10/23/12

2012 Season in Review

It’s been a few weeks now so I’ve had time to digest the 2012 AFM season.

Things definitely started on the wrong foot with the first race of the season being cancelled due to weather conditions. That left six races for the season- four at Thunderhill and two at Sonoma Raceway (aka Infineon, aka Sears Point). I had worked a fair bit on my fitness and mental preparation in the offseason and it definitely showed in my riding- I was much more consistent and my practice times were finally only a second or two off of my race times which really helped me with bike setup and consistency and confidence in my races.
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07/3/12

2012 AFM Round 4

I don’t really have the time to write up a full race report, but I really wanted to send out a few thank you’s to everyone who helped me out at the last AFM round:

Dave, Jim and Nickie at Catalyst Reaction for completely redoing my suspension and working with me over the three days to dial in my suspension and geometry. After struggling with setup at the last Thill round where I felt we were just chasing our tail in circles trying to find something that worked, I was both worried and excited coming to Sears for the first time in nearly a year with a completely different setup. Turns out I was right to be excited- we made an amazing amount of progress in a relatively short period of time out on track and I went faster in practice then I ever had before and then faster again still in my races.

K.C. Gager of BRG Racing for helping me wrench on my bike, talk strategy and mentoring me at and away from the track. I can’t really begin to say how lucky and honored I am to have a sponsor like you who invests so much time and effort into my race program.

Matt Lai for bringing me a rear axle Saturday morning after mine decided it had lived a good life and no longer wanted to be apart of my race program. Thanks Matt!

Frank Shermon for letting me strip the radiator off his bike Saturday evening after my bike started overheating.

Ernie Montague for bringing me yet another radiator Sunday when Frank’s turned out to have problems of it’s own.

Chris Maguire and crew at Pirelli…. actually I didn’t buy tires from Chris this round or anything like that that. I ended up just using the same tires I raced on last round for Friday’s trackday, Saturday practice and my three races on Sunday. Put my personal best lap time at Sears on the last lap of the last race on tires with 4 days on them. :teeth

06/27/12

Cassandra + Hector + JRuby == Awesome

So a few months ago I started looking into using Cassandra for a project. Not being fluent in Java or Python which have excellent client libraries for interfacing to Cassandra (Hector and Pycassa respectfully), I looked into the Perl and Ruby clients.

At the time, none of the native Perl or Ruby clients weren’t nearly as powerful, feature rich or as actively maintained as Hector/Pycassa. I started hacking on the Perl client, but a) realized it was going to need a lot of work and b) I really wanted to use Ruby on Rails as the front end for my application I started looking into using Hector with JRuby. Continue reading

04/9/12

Need help with tcpreplay? Read this!

I’ve noticed a certain pattern come up more and more recently and so I’d just like to make a public statement about asking for help with using tcpreplay:

Occasionally people are testing some kind of top secret device with tcpreplay and can’t tell me how it works or what it does or share their pcap file (because it has some kind of exploit or something like that I guess), but expect me to help them figure out why it can’t “see” the traffic tcpreplay sends. That’s a lot like asking your car mechanic to fix your car, but you won’t let them look at it because you’ve modified the engine to run on tap water and don’t want the mechanic to figure out your secret. As you might imagine, this is both very frustrating and a huge waste of my time.

Simply put, if you see the traffic in Wireshark or tcpdump, but your device under test can’t see it, then it’s most likely either a) bug in your product, b) you’ve miss-configured tcpreplay or c) you’ve got a bad pcap. You’ve pretty much ruled out a bug in tcpreplay at that point. Hence if you want help with determining if it’s A, B or C you’re going to have to give me your pcap, tell me what your product does and some basics about how it works under the hood. Honestly, I wouldn’t consider any of this at the company secrets level unless you’re hacking directly in kernel-space and are completely avoiding the well known socket API’s, but that’s your call.

Anyways, if you’re unable to tell the whole world on this mailing list the above, then your other option is to hire me as a consultant (for a price) at which point I’d be happy to sign an NDA to keep your secrets and we can work off list. Other then that, your best bet is to try and figure it out on your own, but please don’t ask me or the list for help to your problem.

Thanks,
Aaron

01/18/12

Calibrating Thermistors for the Arduino

This is my first post about my current geek project: building a wireless thermometer/alarm/data logger for my Weber smoker. Until now, I’ve been using a Maverick/RediCheck wireless unit which is merely OK. The wireless signal tends to be really flaky and it has only one temp probe. There are multi-probe units available, they’re still missing other features I’d be interested in such as logging the data for generating graphs, measuring ambient temperature outside and setting multiple alarms (for both the food and smoker temperature too high/low).

For my food and smoker temp measuring needs, I picked up 3 food safe probes from Thermoworks for $8/ea. Unfortunately, the probes come with no technical documentation and my email to the company requesting information was ignored. Contrary to my initial thoughts, these probes are not the same as those sold by Maverick or Amwei. I was however able to determine they are NTC thermistors and some searches turned up a way to convert the resistor readings into actual temperatures. Continue reading