Low power RF measurement is of vital interest
when you require a transmitter to be terminated into a 50 Ohms load
and simultaneously require a small rectified voltage for measurement
of RF Level.
This 10cm x 2.75cm double sided PTH board
contains 20 resistors in two banks each of 2K/0.25W to get 50 ohms at
around 10W of maximum power. It is expected to work upto about 500MHZ
with very low SWR.
At 50 ohms Terminated level, a diode rectifier
and an RF bypass capacitor develops DC voltage for further
measurement. A PM2 or more economical PM1
or even a simple Digital meter may be used for measurement of output
DC voltages.
For those looking for Direct RF 50 Ohms
Terminated measurement, diode D1 my be omitted along with associated capacitor/Resistor
and either connect HOT RF to measurement connector (J2) or use a
blocking capacitor (in place of Diode) of suitable value and connect
an RF measurement unit such as PM1 or PM2 to J2.
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