128 has a blinking red light when powered on

[JoeGUSA]

Hello,

I acquired my first Commodore 128 today. The unit worked before I brought it home, but I can't guarantee that the same power supply came home with me. After i connected the power supply to the 128, and the 128 to a monitor, all I get on the 128 is a blinking red power light on the 128. It does the same without the monitor connected.

Being that I'm new to the 128, I don't know what this light means. Perhaps a bad power supply, or something else. Any assistance would be greatly appreciated.

Thank you!

Joe

[LoneWolf33]

Hi,

The power LED is supplied directly from the +5V bus thru a 180 Ohm resistor in the factory setup.
Any flickering or unstable light emission of the LED indicates failure in the +5V supply.

[JoeGUSA]

Thank you!

It turns out that the power supply that I was given was for the Amiga 500 (I didn't notice, and neither did the seller. Honest mistake.). Wrong voltages on two of the pins. I'm going to test with a replacement Commodore 128 power supply and see what happens. Worst case, I can send the 128 unit off for repair.

Joe

[LoneWolf33]

Yes, the Amiga PSU puts out +12VDC and -12VDC where the C128 would expect 9VAC.

[JoeGUSA]

I received my new C-129 PSU, and my C-128 works fine!

Joe

[rbernardo]

Ah, you are fortunate!

Truly,

[JoeGUSA]

As it turns out, my C128 is in need of repair. To be honest, I don't know if I bought it that way due to very limited testing (booting it up before I bought it)), or connecting the wrong provided power supply (Amiga 500) to it when I got it home. I ran the MEMTEST-v1.10 on the system last night and received several different results for each time I ran it. Everything from all is good, to a memory chip (never the same number) being bad, to the colour chip being bad, and a mixture of the results. Before testing, I tried to run a program that worked fine in the VICE 128 emulator, but when I tried to run it on my C128 I would receive a syntax error in the code. I was never able to list the line it referenced. This is what prompted the testing. So I sent the motherboard off to Ray Carlsen this morning. I also sent him a copy of MEMTEST per his request. I'm hoping it can be fixed with available parts. I don't know what the cost to repair will be, but all I want is it to work properly.