HEISHA T30 30km wireless video transmitter is a joke or surprise?

Since T30 released, we received a lot of questions. Here are a few concrete examples.
Customer 1:
T30 radio link claims to achieve 30 km? 
At 5.8 GHz, the 30 km free space path loss is over 137 dB. With a TX power of 23 dBm, RX sensitivity of -80 dBm and antenna gains of 10 dBi (for both sides), your total link budget is 113 dB.  Such a budget could never achieve above 2 km range, and your data sheet shows "Line of sight range" = 1 km+. So where does 30 km come from? That is impossible unless with very large antennas and an antenna tracker.
Customer 2:
I am an engineer with more than 10 years in wireless communication industry. According to my theoretical calculation, your T30 is impossible can reach 30km transmission range with 200mW and 5.8GHz, but your company is unlikely launch fake product. Could you send one sample to test, if it is good, I will pay.

The answer from Heisha:
The equation below shows the path loss for a free space propagation application. It can also be used when calculating or estimating other paths as well. 
FSPL (dB)=20lg(d)+20lg(f)+32.44

       d = distance of the receiver from the transmitter (km)
        f = signal frequency (MHz)
 FSPL = Free space path loss
We calculate HEISHA T30 with this formulate: 
FSPL (dB) = 20*lg(30) + 20lg(5.8) + 32.44 =20*1.48 +20*0.76+32.44=77.24
Based on the parameter of T30, the transmitter power is 23dB and the receiving sensitivity is -70dB, so the sum 93dB is greater than the path loss 77.24dB between a transmitter and a receiver.

HEISHA T30 promotion
To let the customer reassurance, Heisha provides 10 sets T30 and T5 to try out, then pay when you are satisfied. Begin from 27th Feb 2020. First come first serve.
Send email to sales@heishatech.com