The TC08 will woprk fine if not earthed providing you follow some simple precautions.
Try using the laptop on battery power. A switch mode PSU will cause cause grounding problems. Use shielded thermocouple cables with shielded junctions. You will need to ensure no electrical contact with the thermocouple junction and the measurement point. If you can't avoid this, you will need to provide a link from the TC08 to the measurement point. Although this is not advisable in an aircraft!
Noise from the aircraft can be a problem as the TC08 is programmed to reject either 50 or 60Hz mains frequency. A few simple precautions will protect you from interference.
Michael - Tech Support
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