[Order] Buffered Sync busboard

This buffered sync busboard is designed for connecting several Cadet / DIY modules that use the 14 pin sync bus. You need a Cadet Sync generator or Visual Cortex as sync source.

There is one 14pin sync input and nine sync outputs.
The busboard has two C-sync outputs for LZX modules that use RCA connections.
One of these RCA outputs has a vertical RCA socket, the other one has solderpads.
This board needs to be powered and has one 16pin power header.
For more custom systems there are also 2 "screw terminal" type connectors.
Size: 19.7 x 4.1 cm

PCB: 18,- euro
Full kit: 40,- euro
Build unit: 50,- euro
14pin sync cables (5 pieces): 10 euro

Shipping worldwide:
PCB: 5,- euro
Kit: 9,- euro (without tracking) / 25,- euro (with tracking)

PM me for details!
You can also buy it at my Etsy shop

Original design thread: https://community.lzxindustries.net/t/sync-busboard-design-for-cadet-diy-systems/602
This project was made possible by the kind help of L.Larsen and users of the LZX community forum. Special thanks goes to user Agawell for his help testing the RCA sync output.
M.Verhallen / Reverselandfill.org 2019


It was a pleasure, Martijn



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Sync Busboard BOM
r1 3k 1
r2, r10 130k 2
r3, r11 18k 2
r4, r8 75r 2
r5, r6, r7, r9 499r 4
c3 330nF 1
c4, c6, c7, c9 100nF 6
c1, c5 10uF 2
c2, c8 100uF 2
d1, d2 1n4001 2
LED1 3mm led yellow
14pin DIL 2
8pin DIL 1
u1 LM6172 1
IC2 78l05 1
u3, u4 74HC14n 2
sync in, sync out 14pin 10
power in 16pin 1
X1 RCA vertical lumberg

Sync Busboard Buildguide
See here for downloads:

Start your build with the resistors.
R1: 3k (this sets the brightness of the LED)
R2, R10: 130k
R3, R11: 18k
R4, R8: 75r
R5, R6, R7, R9: 499r

D1, D2: 1n4001 (These are for the reverse power protection)
LED: a yellow LED. (If you have another color, adjust R1 for brightness. 10K for red)

IC’s & sockets:
U1: 8pin socket + LM6172 (C-sync output buffer
IC2: 78L05 (the 5v regulator)
U3, U4: 16pin socket + 74HC14N (the buffers for the sync signal)

Put all the headers in, flip the board and lay the pcb on a flat surface.
Solder 2 pins of each header. Now flip the board and check if all headers are aligned correctly.
Correct by reheating the soldered pads. Now solder all pins.
Sync in & sync out: 14pin shrouded headers
Power in: 16pin shrouded header

Start with the smaller ones!
C3: 330nF
C4, C6, C7, C9: 100nF
C1, C10: 10uF
C2, C8: 100uF

RCA output:
Solder the vertical RCA socket at the X1 location. Make sure it is aligned correctly!

The sync busboard needs power.
Plug a 16 pin powercable from your eurorack busboard to the sync busboard "power in" header.
Turn on the power supply. The yellow led should light up.
Turn off the powersupply.

Connect a Sync source module (Cadet Sync generator or a Visual Cortext) to the "Sync in"header.
Connect a module that needs sync (VCO, Ramps, Video input) to the 14pin "sync output" header.
Turn of the power supply and test if the VCO is synced.

The RCA (C-Sync) output can be connected to LZX modules that use this kind of sync method.

If you have a Visual Cortex and a Cadet sync generator , use the Visual Cortex as master.

kit prices are added in the top post

Summer Sale!

pcb: 15,- euro
kit: 35,- euro

Do you still have these? Don’t see them in your Etsy shop. Interested in a kit if you do.

My own stock is all gone :slight_smile:
RawVoltage has my kits:

Thanks for the link. Unfortunately, won’t ship to the US, probably due to Covid

I have one build unit left. PM me if you want it


Sweet, ty! I will PM.

Does anyone have a reverselandfill Buffered Sync Board for sale or trade?

I have a few :slight_smile:

2x syncbus in stock. available as built busboard, kit or pcb.

Thonk & RawVoltage have the rest (about 15x, kits and pcb’s)


Great! I’ll DM you.

I wonder… How hard would it be to modify the Cadet Sync Gen to add the RCA sync output jack? (Sorry if this has already been discussed in the forum)

modding: you can do that the same way as with the syncbus - see the schematic .
@bentoncbainbridge I’ll PM you!

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