Frequency Central Stasis Leak Manual

Frequency central
Build documentation for:
Stasis Leak
Chorus/tap delay/plate reverb
Stasis Leak is a 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.
Main PCB Sockets PCB
Stasis Leak features 3 PCBs:
•Main PCB
•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 3
Belton ABE-FX*
TL084 x 2
BC547 x 1
78L09 x 1
9 volt regulator
1N4148 x 3
5mm red LED x 1
B100K x 4
SPDT toggle x 1
on/off/on
Push Button
100K multi turn
trimmer
6.3mm socket x 7
Male 40 pin header
x 1
Female 40 pin header
x 1
DOTCOM 6 pin
header
* 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.
Affixing the Belton ABE-FX
The Belton plugs in to the Main 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 front first, as shown on the silkscreen, starting with the lowest profile
components, so:
•Resistors, diodes
•IC sockets
•Non-electrolytic capacitors, transistor and voltage regulator
•Panel mount components (pots, switches, LED) –it can be useful to use the panel to make
sue of nice fit.
Now populate the rear of the Main PCB:
•Header for Belton (cut to size)
•Header for Sockets PCB (cut to size)
•Power header
•Electrolytic capacitors, trimmer
Mount the PCB to the panel with the various washers and nuts.

Sockets PCB
•Place all sockets on the PCB, then place the panel over them. This will assure that the
sockets are correctly positioned. Flip the whole lot over and solder the sockets into place.
•Cut the male header to size and place the long end into the female header of the Main PCB
•Present the populated sockets PCB to the panel, making sure the male header passes
through the PCB pads.
•Make sure everything fit’s nice and snug and solder the header into place.
..…you’re done! Next page for calibration…..

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 repeat 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 05/12/19
https://www.frequencycentral.co.uk/