Electronic hardware prototyping system. Solderless, robust and open source. Solves the typical problem of the circuit that works on a breadboard but stops working on a real-world setup. Easy to replicate and compatible with virtually every electronic module.
| From this! | To this! |
|---|---|
 |
 |
Read this in other languages: Español
The system is completely open source, all the files required to create your own system (schematics, PCB, templates, etc.) are available for download.
| 1.Component selection | 2.Position the components on the backplate |
|---|---|
 |
 |
| 3.Wire and program | 4.Attach backplate to the enclosure |
|---|---|
 |
 |
| 5.Close lid and install on the wall |
|---|
 |
The prototyping system is built around 3 key components:
- Backplates
- Electronic boards
- Waterproof enclosures
| Backplates | Electronic boards | Waterproof enclosures |
|---|---|---|
 |
 |
 |
Backplates are flat plates with a distance between holes of 10.16 mm. Backplates are classified as follows: backplates fixed to the enclosure and mechanical adapters for other kinds of modules. The backplates are made in PCB houses, however, they can be built with other materials and processes like laser cutting, CNC machining or homemade with drill and saw!. Source files for backplates
This kind of backplates is fixed to the enclosure, all compatible boards are placed on it. The fixing of the backplate to the enclosure is done with self-tapping screws
| Backplates - fixed to the enclosure |
|---|
 |
This kind of adapters are used to convert modules that have mounting holes, but not compatible with 10.16 mm
| Backplates - mechanical adapter | Backplates - mechanical adapter installed on panel |
|---|---|
 |
 |
The distance between holes of 10.16 mm was found after experimentation, using an universal PCB with 2.54 mm space between holes. The 3 mm of diameter was chosen because it is a very common hole diameter in electronic modules found online)
| Distance test between holes 5.08, 7.62 y 10.16mm | Distance test between holes 5.08, 7.62 y 10.16 mm with nuts |
|---|---|
 |
 |
10.16 mm of distance between holes is a good compromise between compactness and ease of attachment of accessories. Given that the distance of 10.16 mm is an integer multiple of 2.54 mm, these panels could be homebuilt with universal PCB
| Backplate made of universal PCB | Backplate made of plastic sheet and hand drilled |
|---|---|
 |
 |
| Different types of fixing elements for securing boards to backplate |
|---|
 |
To secure boards to backplate (leaving some gap to avoid shortcuts), there are many possibilities like:
This is a single piece element that allows to attach the boards to the backplate without tools, to detach them a pliers are required
| Nylon spacer on board | Board attached to the backplate | spacer from below |
|---|---|---|
 |
 |
 |
This element is composed of 3 pieces: spacer, screw and nut. A screwdriver is required for fastening and detachment
| Nylon spacer with screw on board | Board attached to the backplate | Nylon spacer with nut from below |
|---|---|---|
 |
 |
 |
This element is composed of 3 pieces: spacer, screw and nut. A screwdriver is required for fastening and detachment
| Metal spacer with screw on board | Board attached to the backplate | Metal spacer with nut from below |
|---|---|---|
 |
 |
 |
Electronic boards are classified as follows:screw terminal connectors, breakouts and active boards. Screw terminals are used as a means of interconnection between all of them, because they work pretty well for solid wire and stranded cable, in addition no crimping is needed. Another good point is that many wires can be attached to the same terminal, very helpful for connecting wire jumpers.
This type of board is used as a connection point to the external world, organizing in the same spot, sensor inputs, outputs and power sources. Helpful to provide multiple VCC and GND connection points using wire jumpers. They also have holes compatible with 10.16 mm pitch backplates. Source files for screw terminal connectors
| screw terminal connectors - Different types | screw terminal connectors - unified spot for cable ingress | screw terminal connectors - wire diversity |
|---|---|---|
 |
 |
 |
This type of board is used to convert DIL style electronic modules into screw terminals, they also have holes compatible with 10.16 mm pitch backplates. Source files for breakouts
| breakouts - Different types | breakouts - breakout for Arduino Nano | breakouts - module as a part of a project |
|---|---|---|
 |
 |
 |
This type of board has some electrical/electronic component soldered in to do a specific function. Source files for active boards
| electronic boards - Different types | electronic boards - AC/DC power supply | electronic boards - module as a part of a project |
|---|---|---|
 |
 |
 |
Same as homebuilt backplates, electronic boards also could be manufactured in a similar fashion, as long as screw terminals were used and mounting holes in increments of 10.16 mm were drilled
| homebuilt compatible electronic boards | hybrid project mixing industrial and homebuilt boards | hybrid project installed and working |
|---|---|---|
 |
 |
 |
The system is based on waterproof enclosures with the following characteristics:
- shall have mounting bosses for the PCB or backplate.
- must be able to be mounted on the wall without drilling the enclosure
The enclosures shall have mounting bosses where the backplate will be attached using self-tapping screws. Those holes usually came pre-drilled and should not break the enclosure
| mounting bosses for the PCB |
|---|
 |
The enclosures must have external mounting ears. There are other kind of boxes that have some holes in the back for mounting purposes, but those holes do not break in the enclosure. In this particular case, some additional accessories will be required.
| waterproof enclosures with several wall mounting methods |
|---|
 |
| waterproof enclosures with mounting ears fixed directly to the wall with screws |
|---|
 |
For enclosures with mounting holes in the back, some picture hanging accessories will be handy for mounting them.
| Accessories for wall hanging pictures, flat and Z-shaped |
|---|
 |
| flat hanging accessories | detail of flat hanging accessories | project using flat hanging accessories for mounting |
|---|---|---|
 |
 |
 |
| Z-shaped hanging accessories | detail of Z-shaped hanging accessories | project using Z-shaped hanging accessories for mounting |
|---|---|---|
 |
 |
|
To avoid moisture and dust infiltration in the enclosure at the cable entry point, this system uses two alternatives:
- Cable glands
- Panel mount connectors
Cable glands limit the amount of dust and moisture that can enter the enclosure at the cable entry point. Additionally, they provide strain support, avoiding internal disconnections. Cable glands were available in many sizes according to cable thickness. Usually they were used in permanent installations, because the enclosure has to be opened to disconnect the cables.
| Different types of cable glands | holes for cable glands installation | Power and signal cables through cable glands |
|---|---|---|
 |
 |
 |
Panel mount connectors limit the amount of dust and moisture that can enter the enclosure at the cable entry point. Additionally, they provide strain support, avoiding internal disconnections.Usually they were used when wires need to be disconnected frequently. Sometimes soldering or crimping is required.
| Sample of some types of panel mount connectors | USB-B and aviation panel mount connectors | Power and signal cables through panel mount connectors |
|---|---|---|
 |
 |
 |
| DESCRIPTION | LINK |
|---|---|
| Source files for backplates | Backplates |
| Source files for screw terminal connectors | Screw terminal connectors |
| Source files for breakouts | Breakout |
| Source files for active boards | Active boards |
| Complete finished examples using Misistemita | Galopago |
Misistemita is an open source project by Galopago