I have the "very old" kit version of the TT4 (prior to plus) which has a very limited 5v regulator.
With that limitation, I have not tried connecting very many sensors.
I did a second (remote) LM335Z directly across JP5 (already has 5V).
It has been a long time, so I don't remember exactly how I did it.
I think I removed R12 and replaced with a jumper to be the same as the existing LM335Z.
It might help if we know what sensors are you looking at?
Keep in mind, I believe they are limited to analog sensors with 0 - 5V range.? You can't use I2C or other 'smart sensors' unless you connected them to another board with DAC outputs.
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Rob KB8RCO
