CarVac
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picky picky picky.... Yes, you are correct. However, the same principles apply. The nichrome igniters presented in this thread tend to require a fair bit of current. The Q2G2s don't. My point is that the homebrew varieties may not be reliable when used with modern altimeters due to their current requirements. I wouldn't hesitate to use a homebrew igniter to start a motor but I'm hesitant at this point to use one for deployment.
Also, the telemetrum has a software timer which assumes that the igniter will fire in less than 50ms and only supplies current to the igniter for this period of time. While you can adjust the timing by hacking the source, BDale has said that he's concerned about pulling the processor power supply rail low and/or heating of the PC board traces when using higher current devices. I'm not sure what the raven does as the source code is not open source.
The other main point of the thread regarding ballooning is quite interesting. I'm hoping tfish chimes in.
The Raven puts the outputs high for 1 second, and it's depending on version it's rated for very high currents. The Raven2 is 4 (main, apogee) and 9 (#3 and #4 ouptuts) amps, and the Raven3 is 9 and 20. That's enough for anything. You just need to keep the voltage across the altimeter itself low enough.