After replacing the RF modulator with the TSH7316, the video signal is the same, so the problem is not the RF modulator :-). I will continue investigating the issue. Maybe the problem is in the MOS8701 chip or the VIC-II chip.
I recently acquired a couple of Avid Ultra 320/LVD SCSI drives. These drives are used in the Avid DS Nitris system, which is a high-end video editing system. The drives are:
2 x 146GB Seagate Cheetah 15K.5 drives.
2 x 300GB IBM Ultrastar 10K300 drives.
The drives are in good condition, but they have been sitting in storage for a while. I decided to clean them before using them.
I have a Sun Sparcstation 5, it has installed NetBSD 9, that was the nearest OS that I could install on it. I wanted to try Linux on it, years ago I was able to install linux on a Ultra 1, from the network using a TFTP server and the process was fun. I learned a lot.
Recently I had read about T2sde, a distribution that supports a lot of architectures, including SPARC. I decided to give it a try. There a lot of packages available, and the process sounds easy, and the best the have one of the most recent versions of the Linux kernel. Amazing!
Time to fix the Sharp MZ-700, I have this computer for a while, and it was not working. I decided to fix it. I opened the computer and I found that the power supply was not working correctly. I decided to do the standard procedure, replaced suspects capacitors and voltage regulators. Here are some pictures of the process:
This machine was manufactured in 1982, and it was a very popular computer in Japan. It was used in schools and homes. It has a Z80 CPU, 16KB of RAM, and 16KB of ROM. It has a built-in tape recorder, and it can display 40x24 characters in 8 colors.
The C128 seems to be lossing the brightness signal in the Composite output, the video is fine but the colors are not as bright as they should be.
I’ve decided finally do the cable to connect the C128 rgbi output using composite video. The cable is a simple DB9 pin to phono RCA cable, ground to pin 1 and video signal to pin 7.
These tools are quick-and-dirty solutions, not meant for serious or long-term use. It also serves as a subtle reminder that they should be used cautiously due to their lack of security features :-)
I wanted to have two fast programs to communicate with my old computers, from my linux box, I have three old pcs and I’m using mtcp on them. mTcp includes an ftp client and a telnet client, of course, I could use any of the existing ftp servers or telnet ones, but I don´t want to have more services running, also I thought that would be an opportunity to learn something.
I’m currently working on implementing a CP/M for my small Z80 CPU. As a reminder, this involves a single Z80 CPU connected to a Raspberry Pi, with the latter emulating RAM, ROM, and IO devices.
I spent this weekend diving into the workings of CP/M disks. While there is a Unix tool available to create CP/M disk images , I’ve decided to create my own version using Python.
I’m restoring this wonderful IBM XT 5150, machine powered up, but there wasn’t os. Floppy drive was`t working, I tried to boot from a 720k floppy disk, but it was impossible. So looking for a solution, I found a ISA-PicoMem (https://github.com/FreddyVRetro/ISA-PicoMEM/tree/main) card, a wonderful card that allows you to boot from a SD card, add memory, and is able to connect to a network using wifi and ne2000 drivers, of course you need install mTCP.
I have a long history with computers, starting with a Sinclair Zx81 that I still own, followed by other models and others that I wished for, as time went by.
A while back, I found an old box with some old processors, x386, x486, a few Pentiums first generation and two Zilog Z80. Then I got a kind of retro-feeling in my mind and I watched some YouTube videos about them. One of them was the classic nop-test, I had fun with this for a whole afternoon.
