So I am not at all sure what i was doing wrong then but the measurement went flawlessly, no jumping around this time. (I do not remember if i changed the fobs, today was a long repeater maintenance day)
- 3.2V PTT to UV82 GND ----- 3.3V PTT to Fob
- -18mV to -30mV with UV82 GND ----- -2.2V to -2.35V with fob gnd
- -180mV to -220mV approx UV82 GND ----- -2.6V to -2.7V fob gnd
The probes were not removed while taking readings so negative values were as they appeared on the multimeter.
Sorry i missed your response about low, high and float as it seems it was very close to when I posted. Thank you @N8EI for the information.
@Mike Thank you for the post. I skimmed through it. Will mark it to read later and respond if I can.