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Bias tee modification of HiLetgo RF amplifiers

Hi folks, There are some inexpensive RF amplifiers available in the hobby market by various names. They may be called LNAs, if you consider 3 dB noise figure as low noise. I purchased two of them from Amazon from a seller called HiLetgo. However documentation is sparse and the design is not all that great. People have had frustrating experiences with this type of LNA. Information regarding power supply to this board is practically non-existent, with voltage suggestions ranging from 5V to 12V ! Some even obtained the "magic smoke". Nonetheless they are reasonably cheap and therefore modifications can be done to make them useful. Let us now take a closer look at the board. Figure 1. The amplifier without any modification. Fig.1 shows the board without any modification. There are two SMA connectors and provision to externally power the board. The active element is an MMIC, with N02 as the marking. Other users have identified the MMIC as INA-02184 from HP. It seems to m...