QCX assembly Rev 1.08
45
3.52
Wind and install toroid L4
L4 is type T37-2. It is a small ring with red paint on one side. Each time the wire passes through
the hole in the middle of the toroid, this counts as one turn. The number of turns depends on the
band of your kit, refer to the following table. Inductance values are approximate and will depend on
variations in the core, and how tightly you wind the turns. Do not worry about these variations
which are not critical in this case.
Band
Value
Turns
80m
2.3uH
24
60m
2.3uH
24
40m
1.0uH
16
30m
0.78uH
14
20m
0.40uH
10
17m
0.32uH
9
Try to keep the wire quite tight (but not so tight that you break the wire). Try to spread the turns
evenly around the toroid. Leave about 2cm or 3cm of wire at the ends.
The wire is coated with an enamel insulating paint and it is
CRITICAL to remove this enamel at
the soldered joints otherwise there will be no electrical connection through the toroid!
This
is the number 1 cause of problems with QRP Labs kit construction: failure to remove the
wire enamel.
Содержание QCX 5W CW
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