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Atari 2600 JR Pal Composite Video Mod

July 6th, 2025 No comments
Atari 2600 JR Pal Composite Video Mod

Atari 2600 JR PAL Composite Video Mod for my friend Charlie.

As you can see from the photos i used the RF output hole by removing the female connector and printing with the a 3D printer an adapter that fits perfectly where inside there is a 3.5mm JACK for the composite VIDEO and AUDIO output.

The cable that starts from the female JACK is completely shielded up to the PCB of the Composite Video mod.

Gallery of the work done:

Consoles Modding; XStation,GDemu,DreamPSU,PS1PSU,Battery…

July 3rd, 2025 No comments
Consoles Modding XStation,GDemu,DreamPSU,PS1PSU,Battery,Case,Joypad

Consoles Modding: XStation,GDemu,DreamPSU,PS1PSU,Battery,Case,Joypad

I wanted to share with you some photos of the modding work i made on these two consoles.

Sony PSX #1:

  • Console Sony PSX PAL SCPH-1002 PU8 Late.
  • XStation.
  • PS1PSU.

Sony PSX #2:

  • Console Sony PSX PAL SCPH-1002 PU8 Early.
  • XStation.

Sega Dreamcast #1:

  • Console Sega Dreamcast PAL VA1
  • Original GDemu.
  • DreamPSU.
  • Battery Holder.
  • ML2032 Battery.
  • Black Case.
  • Black Joypad Cable.
  • Black Joypad (Painted)

Sega Dreamcast #2:

  • Console Sega Dreamcast PAL VA1
  • Clone GDemu.
  • DreamPSU.
  • Battery Holder.
  • ML2032 Battery.

Both consoles with 3D Printed SD Card Adapter.

SKS64 Switchless Kernal Switcher C64

July 1st, 2025 No comments
SKS64 Switchless Kernal Switcher C64

A kernal ROM adapter and switcher for C64/C64C/1541/1541C/1541-II

The Switchless Kernal Switcher (SKS64) switch kernals with the RESTORE key on the C64. Automatically switch the kernal in the disk drive using the reset signal. The color of the RGB power LED indicates the current kernal.

The project recommends using the W27C512 EEPROMs but in the lab i have only the SST27SF512 available which are compatible pinouts.

Gallery:

source: https://github.com/bwack/C64-Switchless-Multi-Kernal-27C256-adapter

Nintendo NES (Mattel) PAL with NESRGB v2.0 (CLONE)

June 29th, 2025 No comments
Nintendo NES (Mattel) PAL with NESRGB v2.0 (CLONE)

I wanted to try the 1:1 clone of the RGB mod (NESRGB v2.0) of the authentic Australian kit for the Nintendo NES, this clone differs from the LAVA RGB for a simple reason, this clone is perfectly identical to the original, therefore also compatible with Nintendo NES PAL by Mattel as well as NTSC.

Almost perfect clone if it were not for some obscure reason instead of using the low profile male header strip with good quality round pins they used the square ones, therefore the problems that arise are the following:

  • The socket that must be used must be one of the classic ones with slats that as we know very well ‘tear’ if you insert a male header strip with pins that are too thick, therefore it must be pressed very well and hopefully you will never have to remove the modification again.
  • The pins of the male header strip on the PCB side are too long, so when you insert it into its socket and try to close everything, IT DOESN’T CLOSE! because the RGB mod hits the case, what to do? cut all the pins to the right height and above all all of the same height to ensure that the male header strip can fit flush into the socket.
  • The socket for the PPU seems to be of good quality but it isn’t, they are super cheap rounded precision sockets, if you insert the PPU and then for some reason you have to remove it 99% of the time it will take some of the socket’s bushings with it, so even in this case don’t experiment and go for sure.
  • The metal part on the PCB side can no longer be assembled because it hits the video output connector of the NESRGB, the solution would have been to solder the wires directly on the PCB and put away the connector, absolutely no!

I soldered all the signals on an 8-pin MINI DIN and not with the one supplied as standard with the KIT. The mini din is placed with a ring that i printed with the 3D Printer.

Signals available on the MINI DIN:

  • R G B
  • SYNC Y (LUMINANCE)
  • COMPOSITE VIDEO
  • AUDIO
  • +5V FAST BLANKING SCART
  • CHROMINANCE
  • GROUND

As i was advised by several sources, the SYNC signal for the RGB was not taken from the COMPOSITE VIDEO which carries more information
than could be needed with a substantial loss of Video quality but directly from the LUMINANCE (Y) signal of the SVIDEO signal.

I soldered the PALETTE switch directly on the modulator, you can change three different palettes (Natural, Improved, Garish) from the RF CHANNEL change slot (looking at the photos you can understand better)

The image quality is absolutely incredible, unfortunately the photos do not do it justice, tested with SONY CRT monitors and with OSSC on HDMI IPS LCD monitors.

Gallery:

Source:

Authentic Australian kit: https://etim.net.au/shop/shop.php?crn=203
Clone kit: https://it.aliexpress.com/item/1005008691701911.html

The return of the Hybrid Sid Player Firmware update v2.10

June 16th, 2025 No comments

The return of the Hybrid Sid Player by xAD/Nightfall

Based on the Project and Hardware Schematic by Markus Gritsch released in the years 2011-2015 on the forum dangerousprototypes. Thanks Markus.

Changelog:

v2.10 – 16/6/2025

Added:

  • Added the info of the video mode on the OLED (PAL – NTSC – Both – Unk), the info is alternated with the VB: CIA or VBI.

Updated:

  • Improved the verification of the Socket number for the FPGASid in the configuration file and error reporting on the display if it is incorrect.
    •     FPGASid Socket Error
    •     Check the config.in
    •     FPGASid Disabled
  • The default SID Socket (DEFAULT_SID_SOCKET) in case the Auto Switching mode is used will always be the Socket where the FPGASid has been installed.

Fixed:

  • Playing the song “Acrouzet_-_Your_Indecision.sid” i found a bug, the Player did not choose the right Timing for NTSC and consequently the playback of the song was too slow. The problem was that this song uses VBI with NTSC timing, usually you can find CIA songs with NTSC timing. It was a bug in the player that it couldn’t get the correct information from the SID header.

All in 1 RGB MOD (VideoPac,Intellivision,A2600) Inty Version

April 7th, 2025 No comments
All in 1 RGB MOD (VideoPac-Intellivision-A2600) Inty Version

This RGB mod by Yannick Erb was made to work with three different consoles:

  • VideoPac including BG Color Fix
  • Intellivision only model with LM1886N
  • Atari 2600

I wanted to try this RGB mod even though i am the man who created the ZOE RGB way back in 2013 for Intellivision but on my Intellivision i still had the rough prototype of the mod installed and since i no longer time to assemble a new ZOE RGB interface for Intellivision i have decided to try this one by Yannick which is basically identical to my interface.

I configured the RGB mod to work with Intellivision, there are some jumpers to configure, everything worked at first try the image is clear and stable thanks also to a small trick that this mod includes, a capacitor on the SYNC line that makes the image more stable in some situations.

I also took advantage of completely removing the RF modulator (absolutely useless) and in the hole of the antenna plug i fixed a DIN connector for the RGB / Audio output and SCART Switching, i also replaced the flat of the power cable of the intellivision motherboard because it had completely disintegrated.

Below you will find the usual photo gallery and the download of the GERBER + the files needed to assemble the PCB by JLCPCB.

Gallery:

 

This is the right way for the Scart Switching with source of 12v.

Download: GERBER + Files needed to assemble the PCB by JLCPCB (369)

Project Homepage: https://oshwlab.com/yannick.erb/Intellivision-Secam-to-RGB_copy

November 1st, 2024 Comments off

November 1st, 2024 Comments off

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October 9th, 2024 Comments off

TMS9918A/29A VDP emulation using a Raspberry Pi Pico

August 22nd, 2024 No comments

This interesting project by Troy Schrapel emulates the TMS9918A/29A VDP with a Raspberry Pi Pico.

I wanted to assemble and personally test the PICO9918 with the TI-99/4A using both the VGA output and the SCART (RGB) output and i must say that it surprised me a lot, the image is stable and the software works without any problems.

This VDP emulation has nothing to envy to the F18A implementation although the F18A has some graphics enhancements, improvements that however must be used by new homebrew software for TI-99.

Later i will do other tests with ColecoVision and MSX, i also thank Andrea Ottaviani for helping and beta testing for Troy Schrapel implementation of the SCART (RGB) output which was not foreseen in the first versions of the firmware.

I also point out that the VRAM used by the VDP is integrated into the emulation, so it is not needed,i did tests and removed part of the 4116 VRAM RAM of the TI-99/4A and everything worked regularly, so if you have a TI-99/4A, ColecoVision or other that has the classic corrupted graphics problems (VRAM), the PICO9918 will definitely solve the problem without having to replace one or more non-working RAM.

Brief description of the images that you can see in the gallery:

  • Test with VGA monitor and with scanlines emulation enabled.
  • Test with TV/monitor SCART RGB, in this case i also had to connect the 5v to the scart socket for RGB switching. The 5v go to pin 8 and then via a 150ohm resistor to pin 16, this TV/monitor without this configuration doesn’t display the RGB image correctly.

These are the computer and consoles that use this VDP:

  • ColecoVision
  • CreatiVision Memotech MTX
  • MSX1 Computer
  • NABU Personal Computer
  • Sega SG-1000/SC-3000
  • Spectravideo SV-318/SV-328
  • Sord M5
  • Tatung Einstein
  • Texas Instruments TI-99/4A
  • Casio PV-2000
  • ColecoVision ADAM Computer
  • Hanimex Pencil II
  • Tomy Tutor
  • Toshiba Pasopia-IQ MSX1 Computer
  • Yamaha CX5M MSX1 Computer
  • Telegames Personal Arcade
  • Powertran Cortex

How much did i spend for each PIC9918 ?

  • 2 x Strip Round 40 Gold Pin : €1.15
  • 1 x RP2040 Pi Core Black : €2.69
  • 1 x JLCPCB Assembled (SMD components) PCB : €7.65

More or less for each single PICO9918 complete with all components you will spend €11.49.

The price of each component also includes the cost of shipping and customs clearance.

NOTE: I forgot to write that the composite SYNC for the scart can be taken from one of the two SYNC (H/V) VGA.

Gallery:

Download: Pico9918 (VGA/SCART) Firmware v0.4.0 (PCB v0.3) (496)

source: wikipedia github

Philips Monitor VS0060-80 (CM8833/1084) PSU Repair

July 28th, 2024 No comments
Philips Monitor VS0060-80 (CM8833/1084) PSU Repair

Philips Monitor (Black) VG0060-80 Power Stage Repair, the Monitor turned off unexpectedly without any suspicious noise.

This power stage is practically identical to other monitor models, for example: Philips CM8833 and Commodore 1084, but surely there will be others that mount the same power stage.

Repair:

After removing the PCB of the power stage i took the opportunity to replace also the power switch that no longer worked properly i also replaced the exploded fuse but obviously nothing worked.

The fault was due to the TS132 transistor completely short-circuited, the diagram says that a BU806 is installed but instead a 2SC3795B is installed.

Replaced, still nothing works, i tried with the tester but i don’t find any voltage, even the 300v +/- on the capacitor C112 at this point in addition to the diode bridge (D107/D108/D109/D110) there was only the 47 Ohm 7W resistor R103 to try and in fact it was interrupted, i replaced it with a 5W one, i didn’t have a 7W one in the lab.

I used the old trick of the 100W bulb in series, in my case instead of the fuse to avoid destroying other components.

Everything worked perfectly, the bulb turned on for a minimum amount of time and then turned off and the output voltages of the power stage are all present (125v/15.8v/25.5v).

Gallery:

Download: Philips VS0060-80/CM8833/1084 Schematics (403)

A8PicoCart Flash Multicart for Atari 8-bit (XL-XE)

July 21st, 2024 No comments
A8PicoCart Flash Multicart for Atari 8-bit (XL-XE)

The A8PicoCart is a very cheap multi-cart for the Atari 8-bit (XL/XE) which you can make at home with only basic soldering skills.

The cartridge supports the following file formats: ROM/CAR/XEX and a limited support for ATR files.

Instruction manual, firmware, gerber & STL files and other documentation can be found on Robin Hedwards github page.

You can see a short video i made click here.

Gallery:

Midi Roland MT32 Audio Glitch Repair

July 21st, 2024 No comments
Midi Roland MT32 Audio Glitch Repair

This is a short story of the Roland MT32 Midi repair.

The MT32 MIDI interface had an annoying audio problem (you can listen to the audio files attached to this post).

It seemed like the classic problem of exhausted electrolytic capacitors, but instead it was due to the ROM ROLAND R15449121 (TC534000P) position IC37.

To replace the original ROM it would have been enough to use an OTP Eprom 27C040 which however i didn’t have in the laboratory so i used a FLASHROM AM29F040 by modifying some connections.

The filename of the file used to program the FLASHROM is “r15449121.ic37.bin” which you can find in the archive attached to this post.

Below is the documentation how to adapt the AM29F040 instead of a 27C040.

  • Atmel AT27C040 – 4Mb (512K x 8) OTP, EPROM (32-pin Package)
  • Amd AM29F040 – 4Mb (512K x 8) FLASHROM (32-pin Package)

Tie 29F040 WE (PIN 31) and connect to VCC (PIN 32)
Tie 29F040 A18 (PIN 1) and connect to PIN 31 on Socket or PCB

Monkey Island Audio difference before and after repair:

Gallery:

Download: Roland MT32 (various OS and extra ROMs) (398)

source: Synth Eprom Dumps

Easy way to make a RGB cable for CBS ColecoVision

June 17th, 2024 No comments
Easy way to make a RGB cable for CBS ColecoVision

I wanted to remake the RGB connections of my CBS ColecoVision console a bit and design a new diagram for connecting the RGB video output.

This console was sold with an external modulator (CBS Electronics Adaptateur Antenne 7466 – 6F) that converted the signal from RGB to RF and it seems a Scart cable was not provided for direct connection to the television.

The original ColecoVision D-SUB DB15 to Scart cable that i have doesn’t have the correct pinout but it works perfectly with another ColecoVision always with RGB output but with an internal encoder that converts the Y (B-Y) (R-Y) to RGB signals (PAL Secam Converter A).

This fact is really curious, apparently there are more versions with RGB output as well as RF.

I decided to remove the old RGB cable that i soldered internally about 15 years ago and replace it with an RGB cable connected to the Coleco native connector.

The problem with doing this operation has always been the D-SUB DB15 connector which must be of a certain size, otherwise it won’t fit.

Brilliantly solved using a SNK NeoGeo Joypad extension cable, where we have a DB15 D-SUB connector pre-cast in the plastic where all 15 pins are used (in theory only 14 are needed for the NeoGeo Joypad, but all 15 are connected)

I cut the cable from the neogeo joypad male connector side and soldered the wires to a Scart connector and for the Fast Switching signal before connecting it to pin 16 of the scart i used a 100ohm resistor in series, i did not use the Function Switching signal.

One more thing, the Audio signal from the console native RGB connector is very low, so i made a jumper (see photo) to bypass a resistor and a ceramic capacitor, therefore i took the audio directly from PIN 7 of the SN76489 (Sound Generator).

Of course everything works perfectly.

Gallery of work done: