I'm still on my quest to build a functioning GC myself, and have solved some problems (carrier gas from a PEM electrolyzer, or an inert welding gas, etc.),
And I've aquired the entire gas flow system from an N-P-FID option from a HP7910 GC.

I've been looking at detectors. Building a small FID within a Swagelok 4-way fitting could be a viable option, but then I've come across TCD's like this one:

It's a cheap module, that's basically a complete unit I could couple my column (packed, to be aquired) onto, and then use its recorder output for driving a chart plotter.

The thing is, the instrument sais "%H2" - does this imply it is ONLY suitable for hydrogen, or does it just mean it's calibrated for hydrogen? If it is the latter, It should still be usable as long as i have a calibration curve for each compound i'm trying to quantify, right?

Thanks for your interest,