Calculations, calculation, and nothing more than calculations.

Thanks Gregory! – FR-4 PCB’s dielectric constant ranges Er= 4.2 – 5.0 (assumed Er=4.8). Height of dielectric  =62mils. Thickness of the board = 1.25 oz/ft^2 (1.7mils). Useful link to calculate Z0 =http://www.ekswai.com/en_microstrip.htm . Smith’s calculator resources http://sss-mag.com/smith.html (very good Smith.exe by Prof. Fritz Dellsperger from Switzerland). As a result for MW7IC2425NR1 on reverse calculation impedance on input pin = (58.535 –j9.834) on output pad (5.180+j59.876) – error 20% based on Er error. Looks like will be require for MOSFET to narrow amount of channels from 128 to 32. That can give PAE around 40% - for clamed in spec consuming 25WT it will be 10WT of transmitted power (with harvesting on 3-rd week max = 4- 5WT it will require 6 minutes to harvest for transmitter, 4 minutes for control and 1 minute for transmit totaling == 60sx10K = 600K/min, or 10 minutes == 1 HR picture ,or 24 low resolutions frames, or 15min HR video will be transmitted during 16 hours).  On http://hamwaves.com/antennas/inductance.html for new design of antenna it is Zc=128om. For switches good HMC784MS8GE(10WT, isolation -32dB). Needs to re-trace PCB, order and test. That is best for today.

Dunno (still on Earth)

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