BCI filter in the RX line

Nick Pullen VK4PLN has inserted his 3 stage BCI filter into the RX line.

Filter Details: https://groups.io/g/BITX20/wiki/uBITX-AM-BCI-Filter

Nick cut the trace either side of the new HPF board, exposed a bit of the trace and jumpered onto that.   You need to cut the second trace from the PA side (3rd trace down from the 45MHz roofing filter with the crystal).

Taken from the top trace to the bottom in the photo below, starting from the relay on the left and the PA circuit on top:

1: TX pwr to the PA circuits via R89
2: RX path (between K1 and K3 relays. (CUT AND INSERT HERE)
3: TX pwr to the LPF bank.
4: RX pwr to the receive circuit (R18,R38…)

Nick picked up GND from the 2 unused caps C216 and C210 as can be seen in Nick’s photo above.

Reference

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