The pcb layout
The component print
The picture shows the component print of the PCB. Of course you can't use it for anything except for an overview. Please download the pdf-file instead if you want to see the details.
The printed circuit board is made for two channels. It's possible to do this pcb by yourself. Just make the layout as the schematics. As you can see I have done it. The pcb have groundplane on the upper side (not shown in pictures) which is essential in order to get good results. I haven't made it easy for switching pickup. I gather you will use only one type and also trim for this type.
The solder side
The picture shows the solder side of the PCB. Of course you can't use it for anything except for an overview. Please download the pdf-file instead if you want to see the details.
Almost everyone of the traces are on the solder side. The groundplane is very covering, only a few traces on the component side.
The component side
The picture shows the component side of the PCB. Of course you can't use it for anything except for an overview. Please download the pdf-file instead if you want to see the details.
Almost everyone of the traces are on the solder side as you can see. The groundplane is very covering, only a few traces on this side.
The component side of the real pcb
The picture shows the component side of the PCB, the real one.
The solder side of the real pcb
The picture shows the solder side of the PCB, the real one.
As you can see the pcb exists in the real world. The first prototype of the new pcb is built. I'm quite pleased. If you are interested in building my amp with the amazing performance , don't hesitate to get in contact with me. Since I wrote this for the first time many new QSXM2 amps have seen the day of light.
The extremely small BC847BS and BC857BS
I have equipped the pcb with option for BC847BS/857BS matched pair. This device is very small but it's not impossible solder by hand. See picture below. You can also see the footprints for SMD devices, above Q23.
A SOT363 adapter
This tiny device is two matched ordinary BC847 (=BC547) in one package and they are also isolated from each other.....and....they are cheap! I have only made 5 pieces of this pcb but do I see some interest I will manufacture this little adapter. It fits an ordinary DIL-6 socket and can be a cheap replacement for MAT02 or 03.