Let the meter and sensor come to room temperature and this is what you do to check that you’ve got a good power meter and sensor: 1) Check for any visible damage to the RF connectors of the sensor and the calibration connector on the power meter 2) Connect the sensor to the power meter with the sensor lead 3) Switch the power meter ON 4) Make sure that all power on tests are PASS 5) Let it warm up for 10 – 15 minutes 6) Press the PRESET key and then the CONFIRM soft key to clear all offsets 7) Connect the sensor RF connector to the Calibrate output of the Power Meter, tighten the connector nut by hand holding the sensor body still. DONT rotate the sensor to tighten the connector, you’ll damage it 8) The power meter will probably be reading around -20 dBm at this point 9) Press the CAL / ZERO key and then the REF CF softkey, the display shows 100% 10) Use the arrow keys to change the display to the CALIBRATION FACTOR printed at the top of the calibration chart on the sensor, then press the % softkey 11) The display changes back to reading the power in dBm and you will see the percentage you entered beside the REF CF softkey. 12) Press the ZERO softkey and wait for the power meter to zero the sensor 13) The display should now have dropped to less than -35 dBm, probably to -45 dBm or even less, don’t worry if it’s not stable, provided it stays below -35 dBm 14) Press the CAL softkey and let the power meter calibrate the sensor 15) The display will change back to less than -35 dBm when the calibration has finished 16) Leave for 5 minutes 17) The display should still be less than -35 dBm 18) Press the FREQ/CAL softkey and adjust the Cal Factor to the same value as the REF CF you entered earlier in step 9 19) Press the POWER REF soft key to switch the reference source ON and the reading should be 0.00 dBm or very close 20) Press the POWER REF soft key to switch the reference source OFF, the display should still be less than -35 dBm 21) Very gently wrap your hand around the plastic sensor body without touching any metal parts and the readings shouldn’t change 22) Move the sensor lead about and again it shouldn’t make the reading change, the usual problem areas are at the end of the strain relief If you do all the steps above then you’ve got a good power meter, sensor and lead. I hope that the above helps. We were all noobs once, and if you don’t know the answer then ask! Regards, Dave