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uBITX AM BCI Filter (3.5mhz High Pass Filter)

Based on:http://vk3il.net/projects/broadcast-band-filter/

My PCB : https://easyeda.com/nikpolini/uBITX_3_5mMHZ_HPF-56119a38a46d434fa6d5e9f27e7bdba9

I am still developing/testing this board size and placement

Use T30-6 :

  • 1.622uF = 21 turns (0.4mm wire, 31cm length)
  • 1.461uF = 20 turns (0.4mm wire, 29cm length)

Use 1206 SMD NPO capacitors.

  • 2x 560pF
  • 2X1500pF/1.5nF

The plan:

9mm x 33mm

 

 

 

 Installation:

You need to cut the second trace from the PA side. They are in order:
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...)

I picked up GND from the 2 unused caps C216 and C210