sudden dive

[erhard52]

Again, you do not understand how power measurements work.  Every 6dB doubles the effective range.  What you see is NOT a factor of 6.3.  8dB is a factor of 8/6dB, which is a factor of 1.33333.  However, your measurement is subjective to the antenna angle, distance, and the environment.  This is why a direct connection is used during FCC testing.

100mW = 20dBm
200mW = 23dBm
400mW = 26dBm

What you are missing here is the receiver sensitivity.  Spektrum receivers typically report a sensitivity of -92dBi.  We know from testing built-in antennas in the past (we had a 3 channel receiver we sold that used a similar antenna) that the sensitivity is typically a bit lower.  So we expect the AR410 sensitivity to be -89dBi to maybe -91dBi.  The Nano receiver has a sensitivity of  -102dBi.  That is a difference of 10 to 12dBi.  So, somewhere between 3.333 to 4 times the range when using the exact same transmitter output power.

remember my main objective is to compare the RF output power to the nominal one

my word document link  is all about DIRECT connection measurements - please check it out