ozQRP MDT Construction Manual page 30

Low Pass Filter Coil L3
Take a 300mm length of 0.4mm
enamelled copper wire and wind on 14
turns on a T50-2 toroid. Spread the turns
to cover about 80% of the circumference.
Note the direction of winding as this
makes for a neater alignment on the PCB.
Scrape the enamel off the ends of the
wires and tin with solder before installing.
Low Pass Filter Coil L4
Take a 280mm length of 0.4mm
enamelled copper wire and wind on 11
turns on a T50-2 toroid. Spread the turns
to cover about 80% of the circumference.
Note the direction of winding as this
makes for a neater alignment on the PCB.
Scrape the enamel off the ends of the
wires and tin with solder before installing.
MDT Construction Manual – Issue 2 Page 30