Icom IC-R7100 Discriminator tap Turn the radio off. Disconnect the power source. Remove the top cover. Disconnect the grey coax cable in the corner and remove the power supply carefully. On the main PCB, locate jumper W100. Close to it is resistor R228 found. The top of this one is where the unfiltered audio tap should be connected. Solder a 10K resistor in series with a shielded audio cable to a suitable connector which you mount on the back panel. There are some discriminator tap info available on the net which describes the top of R230 as the tap point. This is very wrong as R230 is a part of a lowpass filter. Data signals will be distorted with decoding errors as a result.