Adding Additional Analog Inputs on a Kantronics TNC

I just posted a how-to article describing adding additional analog inputs to a Kantronics TNC. Out ham radio club was installing a new APRS repeater, and had asked if there was any way of monitoring multiple analog values (specifically, two battery banks, the presence or absence of AC mains, and a temperature reading). I spent some time studying the schematics and doing some research on the web. I was unable to find any specific how-to articles other than vague references to using additional CPU pins. After building and testing the circuit, I decided to post an article describing the process for anyone interested in doing the same thing.

Lego Announces Next-Gen Mindstorms

Lego recently announced their next-generation follow-up to their popular Mindstorms robotics kits. The next generation is called Mindstorms NXT. It appears that Lego has listened to the requests of the Mindstorms community and incorporated several neat features. The most outstanding feature in my mind is bluetooth connectivity. The implications of a bunch of NXT robots able to communicate via bluetooth is incredibly exciting.

There are a few drawbacks, however. First, Lego has announced that there is no electrical compatibility with first-generation Mindstorms. Secondly, Lego has gone with a modified RJ11-style jack for connecting motors and sensors to the main unit. I’m sure that these connectors dragging around a big tub of Lego will soon find the listtle plastic tabs breaking off. Unfortunately, the offset-tab is not the MMJ style used by DEC. Lego has decided to offset the tab in the opposite direction. I have spent quite some time trying to source these connectors, but as yet I haven’t come up with anything.

Lego has announced a beta test program, with 100 lucky testers getting the opportunity to acquire a kit six months before release. In the questionnaire that went with the beta application, it looks like Lego is specifically looking for beta testers to blog about the product, develop models for uploading to Lego’s website, and to develop third party software and hardware for the NXT. If this is the case, and based on their previous history of releasing the developer’s kit, perhaps there’s some hope of a third party developing an interface device between classic Mindstorms and Mindstorms NXT.

My beta application is in. I can’t wait until the release.