PCB-assembly 1/2


Are you starting to assemble a kit bought not directly from schalltechnik_04.de? If yes, check every part again the list of parts.

Really! E.V.E.R.Y. Part!

If anything is wrong -> contact your seller!

If you’re not certain, if it is the correct part -> contact us.

It’s 10 mins invested, that will later safe you headaches.


With that out of the way, let’s start building. 🙂 First we start with the bare pcb and insert the first parts.

On the picture above you see the first step for soldering the JFETs (MMBF5457). One pad per JFET gets coated with solder. Now you take a JFET with tweezers and place and fix it on the corresponding place. Heat up the pad (you coated before) and pin (of the JFET) to get a joint.

ATTENTION: JETs are very sensitive for heat and ESD. This step is the most crucial step in the whole instruction. Take care and take your time.

The other pins of the JFETs can be soldered normally (heat up the pad, put solder to it, done).


Insert 1N4148 diode (1x) and solder it. Align correctly!

Sometimes the marking on the silkscreen isn’t very good to see.


Luckily the land has different shapes. The Cathode (the side with marking) comes in the hole with the square land. (see picture above)

Insert 12V-0,5W Zener-Diodes (4x) (BZX55C12) and solder them. Align correctly!


Insert 1N4007 diode (1x) and solder it. Align correctly!


Insert 100R resistor (1x) and solder it.


Insert 750R resistor (1x) and solder it.


Insert 820R resistor (1x) and solder it.


Insert 1k resistors (2x) and solder them.


Insert 1,8k resistors (2x) and solder them.