QRP Labs QCX 5W CW, Руководство по сборке

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QCX assembly Rev 1.08
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One method of removing the wire enamel is to scrape it off at the ends, either with sandpaper, or
carefully scratching with a knife or wire cutters. However, my favourite method is just to burn off
the enamel. For quite a number of years, the
type of enamel used on copper wire can be
burnt off using the temperature available from
an ordinary soldering iron, immersing the wire
in a blob of solder. (This was not the case, with
much older wire found in vintage valve/tube
equipment). You could also use a cigarette
lighter to burn off the enamel.
Insert the ends of the wires into the correct
holes of the PCB and pull it through tight, so
that the toroid sits up vertically on the PCB.
See photo, right.
Bend the wires over so that the toroid does not fall out while you are trying to solder the wires. Cut
off the excess wire using wirecutters, leaving only about 2mm protruding through the PCB on the
lower side. Now apply solder quite generously from the soldering iron. Hold the soldering iron to
the joint for a few seconds
– I usually count to 10 slowly – and the solder will surround the wire,
which will become hot enough to burn off the enamel. You can sometimes see a small puff of
smoke when the enamel burns off.
Carefully inspect the soldered joints with a magnifying glass to make sure that the wire is correctly
soldered. If it looks li
ke the solder hasn’t flowed nicely and adhered to the wire, then this is usually
a sign that the enamel probably hasn’t been burnt off.
If you have a DVM it is a good idea to check for DC electrical continuity (zero ohms
resistance) between the two ends of the wire.
If you do NOT have a DVM and if the radio
doesn’t work, then we can use the built-in test equipment later, to trace the fault.