Junior bus
About the Junior bus PCB
Junior bus is an open source PCB design by laurent-fr, published on GitHub under the CC-BY-NC-4.0 license. It is a 2-layer board measuring 116.8 × 100 mm, with 13 components from 9 distinct parts.
It belongs with the retro computing designs in this gallery.
From the project
A replica of the Junior Computer (a KIM-1 clone) published by Elektor in the 80's
The Junior Computer is a 6502 SBC made by Elektor in 1980. It looks a lot like a KIM-1.
This is a replica PCB I made with KiCAD.
The best source of information for this computer is Elektor Magazine from 80's , but you can find a lot on this website : http://retro.hansotten.nl/6502-sbc/elektuur-junior/
This board is not a 100% accurate replica, because I have added directly on the PCB a few updates published later by Elektor : a fix for memory decoding needed for the expansion board the main decoupling capacitor C2 was on wrong side of S25 (activate display) which could reset the computer *…
Junior bus bill of materials (BOM)
13 components, 9 distinct parts — part numbers from the project's BOM.
| Qty | Part | Footprint | Refs |
|---|---|---|---|
| 1 | CONN_01X03_SOCKET C64AB | DIN-41612-AB-small-pads | J1 |
| 3 | CONN_01X03_SOCKET C64AC | DI41612-AC-F | J2, J3, J4 |
| 1 | C64AC | DI41612-AC-F | J5 |
| 1 | C64AC | DI41612-AC-F | J6 |
| 1 | C64AB Conn_01x01_Pin | PIN | J7 |
| 3 | Conn_01x01_Pin | PIN | J8, J9, J13 |
| 1 | DB25_FEMALE Conn_01x01_Pin | PIN | J10 |
| 1 | CONN_01X20_MALE Conn_01x01_Pin | PIN | J11 |
| 1 | CONN_01X03_MALE Conn_01x01_Pin | PIN | J12 |
Junior bus design files
The KiCad project lives in the laurent-fr/junior_computer_replica repository on GitHub; these links point at the commit this page was built from.
Junior bus: common questions
How big is the Junior bus PCB?
The Junior bus measures 116.8 × 100 mm, has 2 copper layers and is 1.6 mm thick.
How many components are on the Junior bus?
13 components, from 9 distinct parts, with part numbers taken from the project's own BOM. The full bill of materials is listed on this page.
Where can I download the Junior bus design files?
From the laurent-fr/junior_computer_replica repository on GitHub, which has the KiCad layout, the schematic and the BOM; the links under Design files point to each one.
Can I use the Junior bus design in my own project?
It is published under CC-BY-NC-4.0, which limits how it may be reused; read the license before building on it.
More boards in junior_computer_replica
Junior interface
217.2 × 113 mm116 parts2LCC-BY-NC-4.013
Junior computer
217.2 × 113 mm80 parts2LCC-BY-NC-4.013
Junior computer - Copie
204.5 × 104.1 mm77 parts2LCC-BY-NC-4.013
Junior universal memory
160 × 100 mm38 parts2LCC-BY-NC-4.013
Junior interface conn
91.4 × 19.7 mm9 parts2LCC-BY-NC-4.013
Junior computer display
77.5 × 31.8 mm7 parts2LCC-BY-NC-4.013
Ram adapter
34.3 × 33 mm5 parts2LCC-BY-NC-4.013
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