The following materials are important for assembly:
- Soldering paste for SMD soldering processes, with a soldering temperature of optimally approx. 140 ° C
- Syringe head for easier application of the solder paste on the pads. (Alternatively, it can also be covered with adhesive tape, which should not contain any paste)
- Components that need to be soldered
- Soldering iron
- Normal solder
- Ultrasonic cleaner or isopropyl alcohol
We use the adhesive tape method ourselves, or if there are several pieces to make, a stencil. The stencil is not cost-effective, but it leads to very good results and increases the speed of manufacture.
Apply the solder paste to the print. To do this, the rectangular pads (and only these) are coated with solder paste. Note that the layer should be incredibly thin, there is actually less here.
The SwinSIDc board with overlying stencil. The stencil is aligned so that the holes in the stencil are congruent with the pads on the SwinSIDc, so that a uniform silver surface can be seen.
Then you smear some solder paste on the stencil and spread this paste with an (old) credit card, so that all holes get some of the paste. Make sure that you do not paint over it several times, otherwise too much paste can be pressed on the pad or even under the stencil.
Here is a version that is applied a little too powerfully, the solder paste has easily got under the stencil.
Here is a perfectly successful version, the solder paste is correct and only on the solder pads on it, ready for assembly.
Place the components according to the assembly plan. Make sure that the ARM processor is correctly placed (pins and pads match, take your time and really place it very precisely!). Also check that the dot on the chip also matches the dot on the board.
The whole thing is now in the oven for 30 seconds at 140 ° C. Watch the board. It is normal for the components to move around a bit and align themselves neatly on the pads. However, it can also be the case that certain components float away, i.e. do not move onto the pad but straight away from the pad. This must then be corrected by hand. Please do not interrupt the baking process and do not try to change the times yourself. Also uses an accurate thermostat that shows the temperature to the degree.
If it is too little, it does not bake, if it is too much, the components burn!
In general, the boards manufactured by MARANI.TV are of the type FR-4: This material consists of glass fiber fabric impregnated with epoxy resin. Tg = 105 ° C
The correctly assembled board, right after the oven. Note the points on the oscillator and the ARM chip that they match the points on the board.
Let everything cool and check that there are no short circuits between the legs of the processor. If so, then wet the area with sufficient flux and rework with the soldering iron. It is best to use a magnifying glass for checking.
Use the THT (Through Hole) components, these are the two jumpers and the base. Solder one leg each with the solder and the soldering iron, align and, if it fits, solder the legal pins. Also be careful not to burn your fingers.
Clean the circuit board because excess flux does not look nice and can damage the circuit board in the long run, so remove it. Here, the flux can be carefully wiped away with paper, an ear stick or a lint-free cloth and a little isopropyl alcohol on the circuit board. For the more professional among us (we count ourselves among them :) the board is cleaned in an ultrasonic bath.
This is what the SwinSIDc looks like when it has been completely assembled. Pretty piece, isn't it?
The ARM processor can now be programmed. The ICSP is intended for this, which is not equipped. We simply insert a 2x3 pin header into the programming adapter and simply insert it without soldering into the holes of the ICSP from SwinSIDc and program it. Since the holes are plated through, the ARM can be easily programmed without loose contacts.
The programming adapter can be simply plugged on without soldering. It should be noted that pin 1 is the only rectangular pad on the ICSP and must therefore match pin 1 on the programming cable.
If everything is correct, there are no short circuits, then try it in the C64er. As soon as the C64er is switched on, the LED on the SwinSIDc should light up. If not: STOP, SWITCH OFF! You did something wrong. Pray that the C64er is still alive! Otherwise the SwinSIDc should greet you with a beep and is good!
Configuration of the SwinSIDc by the C64 program. Here you can screw some of the filters and configure the SwinSIDc according to your wishes.
Find, load and listen to games and demos with good sound!
A double SwinSID in a C64 Mk2 in full action