10
Install L1 vertically as shown by its component outline. Pull the leads taut on the bottom of the board
and bend them slightly to hold the toroid in place. Use the magnifying glass again to verify that the part of
each lead that extends from the pad is tinned and shiny
. (If not, you will not be able to solder the lead
properly. Remove L1 and re-do lead preparation.)
Solder the leads of L1. When soldering, make sure that the solder binds well to the leads--an
indication that it was properly prepared. Trim the leads.
Wind and install L2 through L6 in the same manner as L1, using red enamel wire and the turns counts
listed below. (Remember that each pass
through
the core counts as one turn.) The turns spacing should be
adjusted so that the winding occupies about 80% of the core, as shown in Figure 4.
__ L2, 10 turns (8" [20 cm])
__ L3, 11 turns (9" [23 cm])
__ L4, 16 turns (12" [30 cm])
__ L5, 15 turns (11" [28 cm])
__ L6, 16 turns (12" [30 cm])
i
Do not use adhesives to secure toroids to the PC board. They will be supported by their leads.
T3 and T4 are toroidal
transformers
, with two windings (Figure 5). They use the same type of core as L1-
L6 (T37-6). They must be wound with the correct number of turns and the correct winding sense or you
may not be able to align the transceiver.
Figure 5
