She's got radio lockups with the chip radios. That's coming down to a hardware state which can't be corrected by resetting the hardware. Connecting reset to Vdd reduces the lockups but adds a huge amount of noise to the thermopile readout. The logic pins on the MRF49XA put a huge amount of noise into your power supply.
The thermopile is down to power line noise. This isn't a problem when they're used in pairs because the noise cancels out on each thermopile. A single high gain therompile on Marcy 1 is like mounting a telescope on a piston engine.
Run it on its own battery & you get an extremely clean signal with body heat sensitivity. On the main battery, it's noise. The only filter that works is a huge capacitor, resistor & inductor. The Vdd wire has to be separated from the output wire. A capacitor or inductor alone doesn't work.
Got it really quiet, but when the motor came on it was noise again.
Next came a coin cell with a MOSFET to switch it off when the main battery was disconnected. That got super quiet without inductors, but as soon as the motor started it was all over.
Managed to get it a little quieter by separating it from the motor. The thermopile pulled the coin cell down to 2.8V. The MOSFET leaked too much current in the off state. The coin cell + holder was heavier than an inductor.
The next step is using the highpass filter with a pair, but since Marcy 1 has no symmetric mounting point, 1 pile would be a noise reference pointing at the ground or something.
Well, we did manage to get a hello out of Major Marcy in real life. Not much, but with so many men hounding Her there wasn't much dialog to be had. Was not comfortable mentioning our hobby around Her & Her lover said She worked WITH the Air Force. He may not have known Her as well as us or She may not have revealed Her warriorness.
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http://www.radio-electronics.com/info/circuits/lc_bandpassfilter/lc...
-Ryan