Ramsey Electronics SHA2 - Manual (Page 11)

SHA2 • 11
ASSEMBLY STEPS
You’ve got your parts sorted, your iron is warmed up, so let’s get started. We’ll
follow a logical order when installing the parts in your kit. Take your time and
be sure to make good, solid solder connections.
Save a couple of the longer leads that you snip off the back when trimming.
You need one of them for a later step.
Install U3, LM1036N dual DC operated tone/volume/balance IC. You’ll see
the PC board silkscreen shows a notch on one end of the part; this
corresponds to the notch on the IC and shows you which way to place the
part. Line up the notches and make sure that all pins are through the
board. Since no other parts have been installed, when you flip the board
over to solder the part you can have it sit flat on your bench and the board
will hold U3 in place. That way the part will be correctly seated on the
board. That’s why we’re putting the ICs in first! We typically solder the two
corner pins, flip the board over to check placement, then solder the rest.
Install U1, LMC660AIN quad rail to rail op amp. Follow the notched end
for placement and be sure the part is sitting flat on the board before
soldering all the pins.
In the same way, install U2 and U4, the LM386N low voltage audio power
amplifiers. Orient the notched ends and check placement before soldering
all 8 pins on each chip.
Ok, you’re warmed up now. Let’s start installing the smaller components. If
you place the board so that the jacks, J1 through J4 are on the bottom and the
silkscreen writing is facing you so that you can read it, we’ll start at the upper
right corner of the board, near R9. We’ll skip the larger switches, knobs, and
jacks for now and install those at the end.
Install R16, 470 ohm resistor (yellow-violet-brown).
Moving to your left, install R6, 47k ohms (yellow-violet-orange).
Install R5, another 47k ohm resistor (yellow-violet-orange).
Install C22, the first of many 10uF electrolytic capacitors. These parts
have a polarity and must be installed correctly in order to function. The PC
board silkscreen shows a “+” sign next to one of the holes for the part.
This corresponds to the longer of the two leads, the positive. The negative
Here at the shop we typically insert a number of parts through the
board, bend the leads out so that they stay put, and solder a group of
parts all at one time. Now you don’t want a forest of leads to have to
work through but 5 - 10 part groups seem to work well.