开云体育

Hello Dean,
as I thought, that it would be too cumbersome to build the PA LPF as a Manhattan or ugly build, I designed a PCB for the PA LPF, that fits on top of the PA.
The schematic is taken over from the sBitx and includes

• the RX / TX PIN diode (1N4007/MRA4007) switching
• PA LPFs with PIN diode switching
• the SWR-bridge and the ATTiny85 for measuring the FWD and RFL power:

I used SMD components wherever possible. At the left end (antenna) I have allowed for either an SMA edge connector or a BNC connector.

This LPF filter board is mounted on top of the K9HZ RD16HHF1 PA.
It has the same width as the PA PCB and at the rear end the mounting holes are in the same distance as on the PA PCB, to allow a mechanical connection:


I am planning to use this combination of PA and LPF filters also in other transceivers like the T41-EP or the EdenDSP/TRX.
If I would make the LPF PCB as long as the PA PCB it should then even be possible to add a 6m LP filter.

BTW: I don't intend to share the KiCAD design or the gerbers, to avoid any impact to the official sBitx sales.?
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73, Joerg - DB2OO