SWR Meter

This version of SWR meter was initially designed for SSB 6.1 transceiver kit.

Schema

This SWR has a classic balanced schema for measuring power of forward and reflected waves.

SWR Meter Scheme

Balancing is set by trimmer capacitor C3

Details

Ref Qnty Value Description
C1 1 220pF Unpolarized capacitor
C2, C4 2 105 Unpolarized capacitor
C3 1 3-10pF Trimmable capacitor
D1, D2 2 1N34 Diode
J1 1 Antenna coaxial connector, SO239
J2 1 RX coaxial connector, SMA female
J3 1 TX coaxial connector, SMA female
J4 1 Conn_02x01 Generic connector.
J9 1 Conn_01x03 Generic connector, single row, 01x03
K1 1 JQC-3F(T73) PCB Relay
L1 1 470uH Inductor
R1 1 182 Resistor
R2, R7 2 683 Resistor
R3, R4, R5, R6 4 68R Resistor
T1 1 1:10:10 Transformer, single turn primary, split by 10 turns secondary

Board

3D Model Front PCB Back PCB
SWR Meter 3D

It has a slightly unusual design and mounted on the back wall of transceiver. I used sandwich from the TRX wall, one-sided PCB boards which serves as isolator and SWR meter board. SWR meter board has a hole for SO 239 connector and relay to switch between reception and transmission. Also I installed SMA connectors to connect the main transceiver board and amplifier with filters. I used T50-6 carbonyl iron ring transformer and a loop made from central core of 50 ohm coax cable.

I plan to shield the board when I will finish tuning. This little loop picks up the noise from power supply really well therefore I have to shield it.

Download KiCad project

Video

Checkout my design of Band Switch.

Comments:

You can left first comment.

For commenting you should proceed to enter or register on the site.