Shared Projects by skum

A through hole circuit of the TurboPad for the NEC PC Engine (or TurboGrafx 16). This version is fixed and tested.

Based on the schematics found here: http://www.webalice.it/cicciopetito/

An example of the 47k resistor array used is this 4611X-1LF-47K from Mouser but any SIL-11 47k array should do. Switch for the turbo should be whatever SP3T or DP3T you can find.

Inspiration for usage here

RGB SCART breakout board which wires the RGB and sync/composite to solder pads (or pins if you prefer). It has pads for putting in resistors and capacitors which are common when RGB modding CRT sets. Resistor values will differ depending on the set, but for many JVC pro monitors the capacitors C1-C4 will be 0.1uF and while R5, R6, R7, R8 will be terminating 75Ohm resistors. R1-R4 will then be whatever line resistors needed if voltage should be divided, or 0 Ohm. The sync line can be jumped by bridging JP1, which is often comes handy if sync/composite injected directly at the input terminal. If mono is needed, R10 and R9 can be populated with 470 Ohm resistors, and R11 with 20K to mix stereo. All passive components are SMD 0805 size. The SCART plug is a K-SCARTX-024 from Kycon (available at Mouser at least). The board has two RCA plugs (RCJ-02 from Mouser) which supplies direct stereo audio from the SCART. It is switched with SW1 which is a standard DPDT toggle switch.

Completely untested! Based on this: http://www.webalice.it/cicciopetito/archivio/Avenue_Pad_3_Schematic.png

NOTE A mistake has been found, as the four “pre-count” legs on the HC163 are not tied to GND as they should. So if you made this board, you need to put a small wire between these and GND.

If you need to fix it, put a wire like shown on this crappy picture here:

A fixed version of the PCB here: https://oshpark.com/shared_projects/8Hmi1L9I

Based on the schematics found here: http://www.webalice.it/cicciopetito/

A RGB and audio amp for your PC Engine and friends (Core Grafx, Turbo Grafx and whatnot). Mega Drive 2 compatible video plug, RGB SCART cable should have 75Ohm resistors (and preferably also 220uF caps) which the cables should have already. Audio is also amplified a little to get higher volume, as it is a bit low from the expansion port.

• U1 3x23 Pin 2.54mm pitch header. Samtec SSQ-123-02-T-T-RA, SSW-123-02-T-T-RA (or -F-T-RA versions). As such only the left 2x3 pins and the right 3x3 pins are connected, thus any combination of plugs that covers those are adequate. 3xSSW-102-02-T-T-RA should thus also be good, or 2xSSW-103-02-T-T-RA. Note that Samtecs portfolio is huge, and there are many combinations of plugs that will work as long as they have 2.54 mm/0.100" pitch, are triple row and right angle.
• U3 MINI-DIN-9PIN (I used MDC-209 from tme.eu, but MD-90S from Mouser should be just as good)
• C1,C2,C3,C4 0.1uF 0805 MLCC SMD capacitor
• J1 1x02 Pin 2.54mm pitch connector (not necessary if you dont wanna disable the filter)
• R1,R3,R4,R5,R6,R11,R12 10K 0805 SMD resistor
• U2 THS7374 video amp
• C6,C7 2.2uF 0805 MLCC SMD capacitor
• C10,C11 1uF 0805 MLCC SMD capacitor
• R7,R8 1M 0805 SMD resistor
• R9,R10 2K7 0805 SMD resistor
• U4 TS922A opamp SOIC-8
• C5 10uF 0805 MLCC SMD capacitor
• C8,C9 10nF Film capacitor THT L7.2mm, W2.5mm, P5.00mm
• C12,C13 10uF electrolytic SMD capacitor 5x5.3
• R2 75R 0805 SMD resistor

Capacitors should be rated for 16V or higher (lower should also work, no voltages should exceed the 5V).

I recommend to 3D print one of these brackets to provide a mechanical stabilization of the card when used in PC Engine or Core Grafx: https://www.thingiverse.com/thing:3245238

I don’t have a TG16 to measure the port and make a similar for that.

Revision B of this whose sole purpose is the two notches in the side to allow for a small 3D printable case. You can find the case here

Small changes in the routing also, should make no real difference.