Hi, The black lead can be put on the screening of the expansion port or the screening of the RF modulator. Regarding the A/V cable do you need the four pin (+screening) S-Video ending or SCART ending is also good? I guess you can find DIN to SCART cable more easily on ebay. There's a third way: lumi...

Hi, On the '84 brown breadbox which output was connected to the TV: modulator (RF) or the A/V (Baseband)? If you have sound when the TV is connected to the A/V output of the C64, but no sound when using the modulator output, then it's probably a modulator problem. If no sound on both A/V and modulat...

Hi Olivier, Do you need ASCII or binary file? Because they're two different kind of data types: numeric and text. For example ASCII representation of the fisrt three character pattern from the ROM would look similar to the attached picture, where the leftmost pixel in a line is the MSB. These patter...

Hi,

Power supply could cause this (as well), if it's not capable to maintain +5VDC, as the load conditions are changing.
Failure of the BASIC (and maybe the KERNAL) ROM might be confirmed, if the machine boots up from a cartridge.
Defective RAM chip(s) may also prevent the machine from boot.

I'm guessing you didn't liked "TypeWriter" program posted in the other thread ,
or it just didn't worked ?

Interesting site.
I liked the C128 Graphics Booster and the 80 column modification articles.
I also like the idea of preserving old schematics.

I kind of like to have older electronics working, appreciate them for what they were in thier day. +1 Surprisingly many electronic and electromechanic devices from the late '70s and early '80s are still working today, even if they were very complex at the time (meaning lot of discrete components we...

Hi, Glad to hear the good news ! IMHO this board isn't a wrong place for your post. I think the 8050 unit just too rare, especially now. A self test is performed during the stratup of the drive unit, and the result is displayed as LED (all three) flashes. If the LEDs are staying on, that could indic...

Hi, I wrote a small "typewriter" program, it was tested on VICE (since my MPS803 printer was given away). The program starts with a blank screen and accepts text line by line. You can use the backspace key to correct typos within the actual line. Return key will send the contents of the li...

Hi,

The problem may be related to the 1st CIA (Complex Interface Adapter) chip, which is responsible for
the processing of the keyboard matrix and the joystick signals.
Is the cursor stays in place during typing?
...or could you share a video with us about the phenomenon?

Hi, There are two way to do this. If your TV has an unused tuner input (for cable and/or terrestrial frequencies, satellite is not good), then you can connect the RF cable (included to the C64) between the modulator output and the TV's tuner input. Turn on your C64, then perform a channel search on ...

Hi,

You can disable the screen if you put $0B value into the register $D011.
By setting the register value to $1B you can restore the screen.

I hope this is might help.

Update: I've checked the schematics diagrams found on this site, and the horizontal and vertical sync signals (generated by the CRT controller IC) are passed separately to the CRT display (non composite signal). So it is relatively easy to track the vertical deflection control signal's path from the...

Hi, There might be problem with the vertical deflection in the CRT display, some possible reasons: - the driver circuit of the vertical deflection is defective - failure of the vertical deflection coil (short circuit or discontinuity) - no vertical sync is generated or the VSYNC pulses are not reach...

Hello Steve,

Thank you for the reply.
I've also checked the site you've suggested, and I think it will be very helpful.

Regards,
George