I have the R3 board, and have tried to duplicate the anti-pop cct from the R4 schematic (current on a proto board). The mod works ok, in that there is no 'pop' on transitions between TX and RX, but the CW sidetone is no longer coming through the speaker...
I want to try changing the value of R70 from 10, to 1000 Ohms (as per Rev4), but I've never tried removing a surface mounted component before, and a bit scared of damaging the board/resistor (in case I need to put it back).
Can anyone advise how best to go about this please?
I'm even toying with the idea of cutting the tack on either side so I can bridge the gap with a new value (or feed lines to my proto board for testing of various resistances...