Frequency Central Stasis Leak Manual

Frequency central
Build documentation for:
Stasis Leak
Chorus/tap delay/plate reverb
Stasis Leak is a 6HP 48kHz DSP effects module, providing a choice of stereo chorus, stereo plate
reverb and tap tempo delay. Stasis Leak is based around a Belton ABE-FX sub board, which in turn is
based around a Coolaudio V1000 chip.
Dry lift jumper for if you want to use Stasis Leak in an effects loop.
Main PCB Pots ‘n’ sockets PCB
Stasis Leak features 3 PCBs:
•Main PCB
•Pots ‘n’ sockets PCB
•Belton ABE-FX, a fully populated SMD PCB which plugs into the Pots ‘n’ sockets PCB

Key to PCB screen print:
n: This signifies NPN BC547 transistor. Note the correct pinout as shown by the half circles. The PCB
shows the correct orientation for BC547. Other transistor types can be used (eg 2N3904), but please
observe the correct pinout.
Please observe correct polarity of the electrolytic caps, voltage regulators, transistor, ICs etc!
Bill of Materials
33R x 1
100R x 1
1K x 7
3K9 x 4
4K7 x 1
10K x 4
20K x 5
82K x 3
100K x 3
150K x 3
All resistors ¼ watt
metal film.
470pF x 4
100nF x 1
10uF x 5
47uF x 2
Belton ABE-FX*
TL084 x 2
BC547 x 1
78L09 x 1
9 volt regulator
1N4148 x 3
3mm red LED x 1
B100K x 2
B100K x 2
(or these)**
SPDT toggle x 1
on/off/on
Push Button
100K multi turn
trimmer
3.5mm socket x 6
Male 40 pin header
x 1
Female 40 pin header
x 1
Jumper For dry lift
10 pin box header
Little knob x 2
* You can buy this from me, or some other place.
** I prefer the Song Heui tall trimmers because they have a longer shaft and a white notch.
DRY LIFT
There’s a 3 pin header on the main PCB, so you can decide if you want the dry signal to appear at the
output, or just the wet signal.
Normal mode Dry Lift mode

Affixing the Belton ABE-FX
The Belton plugs in to the Pots ‘n’sockets PCB. We recommend using a header to mount the Belton
(see photo on last page of this build doc). This makes the module a little deeper than directly
soldering the Belton without a header. But it saves you from the grief of de-soldering it if you make
an error. Make sure you mount it the correct way around (see photo on the last page of this build
doc).
Main PCB:
Populate the Main PCB as shown on the silkscreen, starting with the lowest profile components, so:
•Resistors, diodes
•IC sockets
•Non-electrolytic capacitors, transistors, trimmers
•Dry lift 3 pin header: note that this sticks out of the front of the PCB.
•Power header
•Electrolytic capacitors, trimmer
Finally, cut 3 male header strips to the correct lengths (11, 11, 6) and solder to the PCB so that the
long legs stick out of the rear of the PCB.

Pots ‘n’ sockets PCB
Populate the Panel PCB as shown on the silkscreen in this order:
•Resistors and diode
•Transistor
•Don’t do the LED yet!
•The upper 2 potentiometers, the switch and the sockets. Use the panel to make everything
line up nicely. You may want to do the sockets 3 at a time, makes it easier to solder their
ground connections.
•The 2 lower potentiometers
•Cut 4 female header strips to the correct lengths (13, 11, 11, 6) and solder to the PCB so that
the black parts stick out of the rear of the PCB.
•Pop the LED through its pads on the PCB –don’t solder it yet! Put the panel back together
with the panel PCB, push the LED through the panel, making sure that it sits right, now
solder it in place.
•Mount all of the panel components using their appropriate washers and nuts.
Plug the Main PCB into the Panel PCB…you’re done!

Tracking/calibration procedure
The trimmer adjusts the voltage offset of both Left and Right outputs. We want the offset to be as
close to 0V as possible.
With Stasis Leak powered up, take a patch lead from the Left output. Using crocodile clips, hook up
the tip to the red probe of your DMM, and the sleeve to the black probe of your DMM. Adjust the
trimmer until the voltage measurement is 0V or thereabouts. It can take a little time for the voltage
to settle –be patient.
Now repeats the process, but this time using the Right output, which should already be close to 0V.
Double check back to the Left output. Then you’re good to go go go go go go go go go go go
RDH 20/11/19
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