EGV-40 CW QRP Transceiver
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When you turn the board over the cans may fall. Fit the can in place, hold it with one hand, and turn the
board over. Use the other hand for the soldering iron, and move the board towards the tin to solder the
can in place. If you have someone to help out, much better!
Toroids L10 y L11 for the LPF
L10 and L11 are identical. T37-2 cores (red toroids with OD 9.5 mm / 0,375 in) are used.
Cut 25 cm (10”) of 0.5 mm enameled wire and wind 16 turns on the red toroidal T37-2 core. Wind the
wire tightly on the core, avoiding loose turns, and spread the turns evenly around the core. They should
be uniformly spread around the circumference of the toroid. Leave pigtails of about 10 mm (0.4”).
Remove the enamel with a cutter to solder the toroids on the board.
The nominal value for L10 and L11 is 1.02 µH.
Counting turns: every time the wire passes through the toroid center hole counts as one turn.
Important: Wind the toroid exactly as shown in the pictures.
Toroidal transformer T5
T5 is an impedance matching transformer. A FT37-43 is used (black toroid with an OD of 9.5 mm /
0.375 in). It has a primary of 8 turns, going to “b” and “b1” holes in the PCB and one secondary of 1 turn
going to “a” and “a1” holes.