Ramsey Electronics LPA1, Инструкция по эксплуатации

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LPA1
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There are three other parts of this circuit. One simply turns on and supplies
power to the circuit. The second, supplies power to the MAV3 amplifier. The
third biases Q2 for proper operation.
Ramsey “Learn-as-you-build” Power Booster Assembly Strategy
Since the LPA1 runs at very high frequencies, it is extremely important that
you follow the instructions provided. Incorrectly installed components, exces-
sively long component leads, and bad solder joints may mean that your kit
won’t work. For reasons like this it is advisable to follow the step-by-step in-
structions in the manual and not jump ahead.
Be sure to read through all of the steps, and check the boxes as you go along
to be sure that you didn't miss any important steps. Before you switch on the
power in a hurry to see results, check all transistors, the MAV3 amplifier, D1
and C3 for proper orientation. Also check the board for any possible solder
shorts, or cold solder joints. All of these mistakes could have detrimental ef-
fects on your kit - not to mention your ego!
Throughout the construction of the kit, we will try to explain the various com-
ponents and their function in the circuit. Who ever said that you can’t learn
something while you are having fun? If your kit has problems, we have also
included a step by step troubleshooting section to guide you through them.
Please remember that most problems occur out of bad soldering technique
and improperly placed components. A clear head and a meter are all that you
probably need to solve the problem. Since it is virtually impossible for our
technicians to “troubleshoot” step by step over the phone, please follow the
troubleshooting guide provided in your manual.
Kit building tips:
Use a good soldering technique - let your soldering iron tip gently heat both
the wires and pads simultaneously. Apply the solder to the wire and the pad
when the pad is hot enough to melt the solder. The finished joint should look
like a drop of water on paper, somewhat soaked in. If the pads have not
heated up sufficiently, melted solder (heated by the iron itself) will form a cold
solder joint and will not conduct. These appear to be dull beads of solder, and
can be fixed easily be applying heat to the pad and wire. Mount all parts on
the top side of the board. This is the side with no traces or pads.
Part installation - when parts are installed, the part is placed flat to the board,
and the leads are bent on the backside of the board to prevent the part from
falling out before soldering. The part is then soldered securely to the board,
and the remaining lead length is clipped off. Please keep in mind that it is ex-
tremely vital to place the parts as close to the board as possible. This is nec-
essary for proper operation over the wide frequency range of the amplifier.