I love computer and gameconsoles of the 80s and 90s. So i try to repair and refurbish this maschines. This is my journey to learn more about retrocomputer, learn better english and develop my personality.
Dear Sir, I am very glad to come across your channel. I have a Sharp PC-4500 computer for ten years, which we used at our local club for programming stations in DOS. A few months ago, the power supply board inside the computer burned out. We replaced the burned-out elements, but the computer won't turn on. My question is..do you have a wiring schematic diagram of your or better PC-4500 computer? I would be extremely grateful. Best regards and thanks in advance
Thanks for your nice words. But i don’t have any schematics for this computer. The reason is I don’t found any of them. Maybe one of my subscribers can help.
@@tomscomputerchannel2925 You are best person because you reply comment for it i wil subscribe your channel and i have last question i have eprom bmw e34 Bosch m3.1 ecu and i want to program the file in eprom but when i read eprom with programmer not have any problem when take the file and edit it after that i want program write 81% and say to me error address and buf have any idea about this problem ? And if i erase the eprom can i add the new file without problem? So thanks stay best channel i wish to continue 👍
I think the Texas Instruments TI99/4A was a good computer, proper design and well manufactured. But if they would have chosen another microprocessor it could have stayed longer in business. Maybe it was fantastic, maybe it was okay, but most of all it was relatively unknown and therefore unloved. A stupid simple microprocessor like the 6502 has till this day a large group of enthusiasts that all come to the conclusion that their beloved 6502 is silly, old-fashioned and totally unwilling to do the work in a correct way, but they love it any way. If Texas Instruments would have made professional TI99 computers for their professional measuring equipment department then maybe they would still have been in business. Real mistakes were made with the TI99, like the pricing and the market the aimed at. Only a few would survive at the games market and Texas Instruments was not one of them.
My first computer.The speech sythesizer was amazing for its time. Best game on the TI994/a was Parsec, a sideways scrolling shooter I could still have fun playing today.
@@adammoss5284 i have found a emulator here, but i dont know much about emulate this machine. www.99er.net/emul.shtml You’re right the TI99/4a is 16 bit but not for all functions. Only internally it has a 16 bit bus.
Amazing how cheap everything has gotten since I last worked with windowed parts. Back then in the parallel port programmer days there were few affordable options for the casual hobbyist.
Fellow Sharp PC-4521 owner here. Mine is missing the HDD controller, which makes it impossible for me to connect any kind of hard drive to this laptop. I even tried parallel port SD card reader specifically designed for old DOS laptops to no avail. I want to ask you if its possible for you to take high quality photos or even better, scan both sides of the HDD controller card? Creating a clone of the HDD controller would help make all of those Sharp PC-4521's useful since then our only alternative for storage wouldn't be overpriced 5" external floppy disk drives. Thank you for the video and making more people aware of this laptop!
@cicalone70 no it’s not a problem with the video chip. It’s an issue from the camera I use. The lighting was not that good that my camera showed the correct colors on the screen.
Hello, could you give a picture of the front side of the FastRAM for the A600 from the clip! I have the same one but it's missing components and I want to restore it but I don't know what they are! Looks like yours!
Hi, what components are missing in your A600? A good way to finding missing components are the service manual. It’s available in the internet. There is also the value and type of the components. 😉
This C64 is an later model. It had this keyboard from factory. All other features from Aldi C64 are existing on it. It could be that commodore hat this keyboard available only.
Yeah, that’s right. I will see, how i can fix this. Also the sound is missing. I think some issues came from leaked caps. There are some inside. The rest i will see.
The performance of that cf card is rubbish.... If thats how poor it is, i would skip cf card altogether and just get a ide 2.5 drive (an old laptop drive) or sata adapter.
Hi Bob, sorry for answering that late. The Keyboard dongle ist needed. I forgot to order this pcb. The dongle are some bridges on the connector. I made this with wires.
I got a used PS2 and it stays on the menu. But after a couple of minutes it does eventually boot the disc. Not ideal though, but I'm glad it works at least
It seems, there could be a fault of the laser-unit. The Laser-unit is a common failure. It could be faulty capacitor maybe. It’s difficult to say without testing.
Have you tried to change the VIC-II chip? Or resolder the chip/socket for the VIC-II? I wonder if there is s bad connection/bad VIC chip. Sometimes it manages to read the character data and sometimes it doesn't
@@tomscomputerchannel2925 Fingers crossed! Also, an idea is to take the chip out, spray the socket with contact cleaner and replace the chip again. Could be a bad connection?
I washed the plastic. Then i applied this on the plastic, wrap this in plastic foil and then lay it in the sun. After a few hours the yellowing disappears.
If you want support me like and subscribe to my channel. And i'm now on Patreon you can support me here as well. www.patreon.com/tomscomputerchannel That will help the channel grow, for more exciting videos.
Have you thought about an accelerator upgrade? I have a Furia-020 in my machine, and though it is picky with CF cards, then it is working fine with a micro drive. Else there are the low budget PiStorm and then this new solution with 030 and 64mb Ram. But that is a tad expensive compared to Furia.
Ich verzinne eigentlich bei den Widerständen und Kondensatoren ein Pad. Da halte ich eine Seite des Bauelements drauf und schmelze es fest (ich sage bewusst nich „löten“ dazu, weil ich diese erste Lötstelle als minderwertig betrachte. Dann löte ich die andere (unverzinnte) Seite fest und löte danach noch einmal die erste Lötstelle. Bei ICs verzinne ich zwei, diagonal gegenüber liegende Pads klebe den ersten Pin fest, korrigiere möglicherweise die ausrichtung, schmelze das gegenüber liegende Pad fest und löte die Pins. Und löte die ersten zwei Pads richtig fest. Man benötigt nich so viel Lötzinn. Es sollte eher eine „Hohlkehle“ als eine Perle sein. 0.5mm Lötzinn ist für SMD ganz gut. Unter dem Microskop sieht man ja gut, wie das Zinn fließt.
@@tomscomputerchannel2925 Bei wem nicht? Bis zu IPC-Zertifizierung habe ich noch viel zu lernen 🙂 Früher hatte ich ja immer jemanden zum Prototypenbau.
Hey Guys, thank you for watching my videos. To support the channel like and subscribe i would appreciate it. Thats help the channel growing. You can also support me on Patreon if you want to. Here is the Link to Patreon: www.patreon.com/tomscomputerchannel
