Tech / Repair Archive

Commodore SID chip variation videos

If you’ve been watching my streams or VODs recently on Twitch, you’ll have seen that I’ve got back into Commodore 64 stuff.  Since I only stream real hardware like the hideous poser that I am, I got

TourVision – V1 system discovered!

A contact of mine in Spain came across a strange motherboard while searching for carts for me – while it’s of limited usefulness due to the limited number of V1 cartridges and functionality, it answered many lingering

Using MAME to assist with repairing Nova 2001

If you’ve seen my recent new arrivals post, you may have noticed a broken Nova 2001 PCB.  I’d had a quick look at it when it arrived  and managed to at least capture the error message, but

Nichibutsu Mahjong visual glitches

I’ve seen this on three different boards now, and it turns out that certain families of Nichibutsu Mahjong hardware can have problems with colour bleeding and minor visual glitches.  For example Club 90’s and The Lady Hunter

Teenage Mutant Ninja/Hero Turtles RAM fault

This one is a simple fix but I thought I’d use it to demonstrate a technique for making minor track repairs.  I received a TMHT PCB today which on testing showed this mess: While the screen is

TourVision picture problems

As discussed in other articles, the TourVision system is just a PC engine automation platform & interface.  The RGB output of PC Engine consoles is rather low, especially compared to JAMMA standards, and as such the motherboard

TourVision – busting open the BIOS data

This is a followup to my previous article on the TourVision system here: http://blog.system11.org/?p=1785 I was playing around with the system recently, and I noticed that Dragon Spirit wouldn’t run.  It would boot, but just sat there

Mutant Night bootleg sound restoration

Mutant Night is a pretty rare game, even with it being poorly known, weird and somewhat unpopular it’s still hard to find a real one.  Thankfully bootlegs exist and some are almost perfect clones. Unfortunately there’s a

28 pin 1mbit MASK ROMs & Life Force

From time to time, you’ll come across ‘problem’ parts – like the Jaleco ROMs in my last post.  Another long standing pain in the neck are 28 pin 1mbit mask devices used primarily by Konami and Namco.

Reading HN62312 and HN62304 chips

I recently ended up buying a Jaleco Lord Of King (Astyanax) PCB, which also came with a P-47 ROM board – or maybe it was the other way around.  When I looked at it and my existing