Pin Confusion #u3s


KI7MWA
 

Page 15 of the U3S construction manual says: "To run the transmitter using the 5V supply, be sure to connect a wire between the +5V and PA pins. This is shown by the short red horizontal line in the diagram (below)."  But, in the diagram there are actually TWO short red horizontal lines, one between the second and third pins of the 4-pin header next to the capacitor labeled C1, and another between the second and third pins of the 11-pin header at the edge of the board, the pins labeled +5 and Heat.

With no jumpers installed, my DVM shows continuity between the +5 and Heat pins.  Is this correct? Or do I have a short somewhere?

With the Si5351 module removed I have NO continuity between the +5 and Heat pins.  Does this mean I have a short somewhere on the Si5351 module board?

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