QRPproject DL-QRP-AG, Руководство пользователя

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Version: 13. September 2004
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The next part is a higher effect version in a TO220 casing. This is
kept at 10 Volts by an external circuit. NOTE: The casing of this
regulator is NOT at ground potential, so it must be mounted
isolated. The picture shows the TO220 casing. In the placement
diagram, the parts is shown from above. The fat, black line shows
the metal strip, and show the mounting direction. In the kit you
find a heat sink for this part.
[ ] IC15 LT1086CT TO220 E1
The following fuse holder consists of two parts. To make them fit
later on, it makes sense to mount the fuse during soldering.
[ ] SI-1 Fuse holder F1
[ ] Fuse 2,5A F1
Finally we mount the soldering pins. Press the short end of the pin through
the hole in the pc board with a pair of pliers. No violence, but some pressu-
re is needed. Solder to the down side of the pc board.
[ ] PIN50 + 12V G1
[ ] PIN51 Ground G/H1
[ ] PIN46 E1
[ ] PIN45 E/F1
[ ] PIN47 E1
[ ] PIN18 C5
To connect the external power, you will
need a coaxial power connector and proper
wires. In the bag with peripheral parts, you
will find the connector . Solder two wires of
about 10 cm to the connector.
To avoid later damage, it makes sense to
use a red wire for the plus, and a black wire
for the minus pole.
[ ] Connect pin 47 of the pc board with pin 18 with a short piece of wire
and two [Steckhülsen - please change!], to supply the upper part of the
board with +10 Volts.
[ ] Connect pin 45 and 46 with a short piece of wire and two of the
plugs provided for the pins. Here you will mount a switch later on.
Testing Section 1
1. Visual inspection.
As a first test, inspect every section with a loupe to find shorts. Take this
test seriously. Even a master solderer makes shorts with bent leads or small
blobs of solder. Or even unsoldered soldering spots! Parts are overlooked
more often than you think. Also check the values of all parts: Right part in
right place? Electrolytic capacitors correctly polarized? Diodes?
2. Resistance test
Measure the resistance from plus to minus at the pc board (pin 50 and 51).
This should be larger than 50 kOhms.
Allways use the black lead of your ohm-meter conncted to ground. Be aware
the measurement not to be stable if there are electrolytic caps in the
measuring path. The will be loaded causing a wandering restistance value.
The resistance test is done to find shorts. Shorts will be shown by the
meter by a clear ZERO Ohm resistance.
3. Smoke test
If Speaky passed the resistance test, try applying voltage to the pc board.
Put between 10 and 15 Volts between pin 50 (PLUS) and pin 51 (GROUND).
Use a laboratory supply with a current limiter, or put a 100 mA fuse in line.
Is is good sense to use a regulated power supply with a current limiter.
Reduce the current limiter to its lowest before connecting!
Allwarys turn the power supply on before turning on the device
under test. ALLWAYS! Many power supplies have an initial
voltage peak, large enough to kill your apparaturs!
Having connected the Speaky to the power supply, keep an eye on the
current level and another eye on the pc board. Smoke is a definite sign of
malfunction, as is a current of more than 20 mA.
4. Funkctional test: