QRP Labs QCX 5W CW, Руководство по сборке

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QCX assembly Rev 1.08
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14) Finally, cut and un-twist the loop which you created first, which was between the 30
th
and
31
st
turns of the toroid winding. Push the wire which came over the toroid body, into hole
7. Now you have three turns of wire, which make up “secondary 2”, between holes 7 and
8.
15) The last wire came from under the toroid body when you cut the loop; this wire is the
other end of the 30 turns “secondary 3” winding, so insert it into hole 2. It is already near
to hole 2 and you don’t need to push it under the toroid body as you did in previous
steps.
Take a moment now to review the situation. You should be able to identify the four
windings of T1, and squeeze them together neatly as in the photo, to verify that each end
of the 3-turn windings goes into the correct holes.
16) Under the PCB, you should have three pairs of twisted wires, and one pair (that you
installed last), un-twisted.
17) Now you can solder the eight connections under the PCB. I recommend doing one pair of
wires at a time; this way, the other wires will hold the toroid in place and stop it falling out.
Start with the two un-twisted wires. Pull each wire tight, bend it over at about 45-degrees,
and cut it 1-2mm away from the PCB surface. Having bent the wire prevents it from
falling out. Now solder the wire. Remember to hold the soldering iron to the joint for 10
seconds or so, to allow the enamel insulation to burn off.
Repeat for all the other wires, one pair at a time, until all eight are soldered. If you have a
DVM, check for DC continuity (zero ohms resistance) across each winding. If you do not
get the expected continuity, then it means either
a) you have not managed to scrape or burn away the enamel insulation properly so there
is no electrical connection AND/OR
b) you put the wires into incorrect holes AND/OR
c) your expectation is wrong because you have not identified which pad on the PCB is
labelled 1-8 in the diagram.