Giving just the right amount of electrical power to your Commodore 64’s is vital to ensure a stable operation. Voltage drops may give rise to stability issues while too much voltage will undoubtedly fry the delicate chips on the old C64 motherboards. The latter is … Read more
It’s finally time to show what has been clutting up my workbench for way too long! Back in 2015 I got my hands on two C64 Reloaded boards (link) and installed them inside cases from the Kickstarter campaign (link). I also entered the Phase5 Indiegogo … Read more
…and a yellow longboard have been added to my collection of Commodore 64 motherboards. The yellow Assy 250425 Revision B longboard is in really great shape. It has a MOS 8500 MPU which is quite unusual for the long boards. Normally they have MOS 6510 … Read more
During the last couple of weeks I’ve received 8 (!) broken Commodore 64 machines that were in need of repair. The repair logs of three of them have already been described here (link), while the latter five had issues ranging from faulty Serial Ports (link, link, link), … Read more
I just got this stack of broken and badly discolored Commodore 64C’s from a friend. The cases were made in China, Hong Kong and Germany… The first board is an Assy 250469 Rev. A board that had a broken keyboard – some of the keys … Read more
The most common cause of a black screen on the old Commodore 64 long boards (link) is a broken Programmed Logic Array (PLA) chip located at position U17. Based on different input signals, the PLA creates chip select signals and controls which chip is to … Read more
The semi analog SID chip (Sound Interface Device) is an electronic music synthesizer and its distinctive sounds are easily recognized by any Commodore 64 owner. Back in the days, most SID tunes ended up in games or demos to basically support the graphics on the … Read more
Turning the Commodore 64 off and on every time it needs to be reset, may eventually cause the power switch to malfunction or even put unnecessary stress on the fragile chips. Because of this, people have been installing reset switches for years using a momentary … Read more