Mercury Champ 600, Руководство пользователя

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30 Fender Champion “600” •
Mercury Upgrade Kit
This project and its documentation is the result of technical investigations made by the engineering staff of Mercury Magnetics . The disclosure of the information herein may pertain to proprietary rights and
the furnishing of these documents does not constitute an expresed or implied license to use such materials.
such as PVC tubing or a dowel rod. Make sure
enough of the copper wire is exposed to act as a
contact point.
Step 5 : Attach the alligator clip to one of the
capacitor’s leads. Be sure the amplifier is
completely powered off before doing so.
Step 6 : Touch the bare wire end of the PVC tube
or dowel rod to the other lead of the capacitor. It
is very important to not touch any of the exposed
leads or wires at this time. Hold the bare wire on the
lead for at least several seconds to fully discharge
the capacitor.
Step 7: Test the capacitor with a multimeter to be
sure all voltage has been safely removed.
Discharging Capacitors
in a Guitar Tube Amp
Take pride in how safe you can be.
You can’t play guitar or build amps if you’re dead.
You may have heard various horror stories about
things inside amps that can store a charge that can
kill you. Well, it’s true! However, those dangerous
voltages can be easily drained in just a few
minutes, so take your time and don’t rush.
It is absolutely vital that we drain the filter capacitors
in the DC power supply before working on any
guitar amplifier. These often hold a charge of
several hundred volts, which is potentially deadly.
Capacitors can hold their charge for a long time,
even with the power off and the amp unplugged. It’s
very important that we learn to properly “drain” this
residual voltage so that we may safely work on the
inside of our amplifiers.
What You’ll Need:
1. Safety glasses. Always use safety glasses. If
you wire a capacitor in backwards there is a very
good chance that it will explode in your face.
If you haven’t given the capacitors a couple of days
to discharge – or if you just want to be cautious –
you can use a short length of insulated wire with
alligator clips on the ends to discharge them. First,
make certain that the amp is unplugged. Attach
one alligator clip to a capacitor’s positive (+) lead,
then touch the other clip to the amp chassis several
times. Repeat the procedure for each capacitor
marked with a voltage (VDC) rating higher than 25.
The time spent on this precaution can spare you
from a numbing electric shock that you’ll remember
long after the amp is back together.
How to Discharge a Power
Capacitor in Tube Amp
by Kevin Krause
eHow contributing writer
To be able to properly test and troubleshoot your
tube amplifier with a multimeter it is important to
discharge the capacitors located in the amp’s power
section to avoid false readings. Capacitors act as
short-term batteries, storing a charge that can be
called on by other components. This charge will
remain in the capacitor even after the amp has
been powered off, and can produce misleading
voltage readings along circuit paths. Because of the
high level of the stored power in the capacitor, safe
discharging is a must.
Things you’ll need:
1. High wattage resistor
2. Alligator clip
3. Copper wire
4. PVC tube or dowel rod
5. Soldering iron
6. Solder
7. Multimeter
Instructions
Level of difficulty: Moderate
Step 1 : Strip about 1/4 inch of insulation off each
end of a 2-foot length of insulated copper wire, and
solder one end of the wire to one of the leads of
a high wattage resistor. The resistance required
can be determined by adding 5 to 50 ohms per
volt of the capacitor’s rating. For instance, a 100V
capacitor would require a resistor rated anywhere
from 500 to 5k ohms.
Step 2 : Attach the other end of the wire to an
alligator clip.
Step 3 : Solder the free lead of the resistor to a
short piece of bare copper wire.
Step 4 : Tape the resistor and bare copper wire to
one end of a length of non-conductive material,
Filter Capacitor Discharge Tool