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Reading Ceramic Disc Capacitor Values
Ceramic Disc capacitors will typically have
the actual value and voltage rating printed on
them.
Reading Diodes
The diode(s) included with the kit are
directional and it is very important that
they are installed correctly according to the
circuit. Pay close attention to the orientation
of the silver band that is around the outside
of the diode. Depending on the direction they
are going will determine how they conduct
or rectify the AC voltages. For example, in
the case of the Princeton Reverb, the band
on the diode is facing towards the incoming
AC voltage, meaning it is going to block the
positive cycle of the AC voltage but rectify
the negative cycle giving the negative DC
voltages needed for a xed bias amplier.
SECTION 6:
SOLDERING BASICS
Before you start slinging solder in your kit
or if you have never soldered before, take
a moment to read over this section about
soldering.
When assembling your amp kit, whether
it’s putting components on the eyelet board,
wiring up the tube sockets or connecting
wires to the potentiometers, the rst thing you
want is a good solid mechanical connection.
So for example if you are connecting a wire
to a pin on a tube socket or on the back of
a potentiometer, you do NOT want to set
the wire on the pin or let it oat loosely and
throw a bunch of solder on there. Solder is
not a great conductor, specially some of the
newer lead-free solder, think of it as more of
a semi-conductive glue. So what you want
is a solid physical connection between the
components that you are connecting together.
For example, when soldering to a tube
socket, you would want to create a hook with
the wire or component lead, hook it through
the pin, then use a pair of needle nose pliers
to pinch the hook together around the pin.
Now the wire has a solid connection to the
pin, so even if solder were to fail, in theory
you have the components connected together.
After you have created the mechanical
“bond”, then you can add a little solder to
help solidify the joint.
Working with eyelet boards
When installing components onto the
eyelet boards, you want the component to
lay or sit down onto the board, feeding the
leads into the eyelets and them bending
them underneath the board. Once all the
components are installed on the board and
the connecting wires are attached as well,
then start soldering the joints. After they have
been soldered, be sure to clip the excess leads
that are underneath the boards so that they do
1
0
p
F
not short against other components.
PRO TIP: There is an exception to laying a
component down on the eyelet board and
that would be higher wattage resistors are
in the power supply OR if the amplier
is running the power tubes in a cathode
biased conguration. These components
are dropping voltages across them during
operation, which results in excess heat, and
needs to oat a little above the board to
dissipate the heat.
Soldering a connection
When soldering a connection on an eyelet,
tube socket or potentiometer, make sure that
you are heating the component lead as well as
the pin or eyelet. Then slowly ow the solder
into the connection. The solder should liquify
and spread over the connection. It should
only take about 2-3 seconds for the
connecting component leads to become hot
enough to ow solder. If it takes longer,
double check the temperature of your
soldering iron and make sure the tip of the
iron is clean. A quick way to tell if you iron is
hot enough and clean is to take a little solder
and touch it to the tip. The solder should melt
almost instantly and stay on the tip, NOT
bead up and fall off.
PRO TIP: It doesn’t take a lot of solder to make
a good connection. Again think of the solder
as semi-conductive glue that holds your
connections together.
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