BF-22 SALLEN KEY FILTER V3.3 - ASSEMBLY GUIDE – REV. NOV 17
FRONT PANEL COMPONENTS MOUNTING TIPS:
Now we will proceed to mount the jacks, potentiometers, switches and LEDs. This part of the
assembly is CRITICAL. Please take your time and read the following instructions carefully.
These components must
NOT
be soldered until they are placed on the PCB and fully attached
to the front panel.
There are two reasons for this:
•
The height of the panel components are not all the same. Because of this, if not
attached properly before soldering, they will not stay properly seated against the panel.
This might cause mechanical stress reducing their life expectancy and in the worst case
cause them to break.
•
The second reason is that it is very difficult to align the components to the holes if the
panel is not positioned prior to soldering. In the case of the LEDs, they are almost
impossible to set to the correct height without reference to the front panel.
OPEN MINI-JACKS BAG
MINI-JACKS
Place all the mini-jacks onto the PCB ensuring they are on the silkscreen side, but
don't
solder yet
.
Caution:
the switch nut and the jack nuts look the same, but they are not equally sized and
will not fit in each others' thread, so make sure to keep them separate!
POTENTIOMETER
Now place the potentiometer on the PCB. Do not place them all the way down, leave them loose but...
don't solder them yet!
Qty Type
Name on PCB
8
Single (3pin) 100K
CUTOFF_A, CUTOFF_ATT_A, CUTOFF_ATT_B, CUTOFF_B,
RES_INIT_A, RES_INIT_B, VOL_IN_1, VOL_IN_2
TOGGLE SWITCHES
Place the toggle switches onto the PCB where the silkscreen indicates but
don't solder
them
until they are secured to the front panel.
Remove both nuts and the tabbed washer. Keep the knurled washer on the switch. You will
need only one nut for securing the switch to the front panel.
Qty Type
Name on PCB
3
Single two position
LINK, LO-HI_SELECT_1, LO-HI_SELECT_2
LEDs
Place the LEDs onto the PCB minding, their polarity, but
don't solder them
until the front
panel is in place. This is the only way to solder them in the right position.
The long leg is the positive and the short the negative. On the PCB the square pad indicates
the negative side and there is a + symbol to indicate the positive.
Qty Name on PCB
2
LED1, LED2
6
