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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: anagrama on October 06, 2010, 10:24:40 PM

Title: Amiga 4000/40 Hep Needed - No Display
Post by: anagrama on October 06, 2010, 10:24:40 PM

Hi All
   
  I've just received an Amiga 4000/40 which doesn't produce any display.  When I switch it on it powers up fine and the hard drive starts  spinning but the signal turns to a black screen on the television and  that's it. I've unplugged the hard drive, removed the memory modules but  still the same thing happens. Ive also tried the obvious such as such as different cables, different tv/monitor but the same thing still happens.
   
  Does anybody have any advice or possible know what the problem could  be?
   
  Thanks

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Darrin on October 06, 2010, 10:43:56 PM

Do you get any colour flashes as the system boots?

How is your jumper set on the motherboard, PAL or NTSC?

If you put a floppy disk based game in the drive does it appear to load it?

Did you connect an Amiga monitor or use an adapter to connect a PC monitor or TV monitor?

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: mohican on October 07, 2010, 01:28:12 AM

Hi,

The oscillator's contact problem can show the same effect. Try to take out and put back into the socket.

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: mechy on October 07, 2010, 02:07:17 AM

Try reseating the A3640 board..
reseat the memory on the motherboard also.
did the machine have any battery leakage?

Mike

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Steady on October 07, 2010, 07:11:44 AM

@anagrama:

Sorry I can't help, but my A4000/40 also has this problem, though it works perfectly fine through a graphics card. Nothing comes out the RGB port and the sound is almost non-existant. I think it might be an issue with leaky capacitors but I don't know how to fix these things. I'd be interested to know if you get an answer that fixes this.

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Darrin on October 07, 2010, 01:44:32 PM

an Indivision 4000 might take care of the RGB problem.

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Cosmos Amiga on October 07, 2010, 02:29:59 PM

>Nothing comes out the RGB port

=> Ricoh


>and the sound is almost non-existant

=> Capacitors leaking

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Steady on October 08, 2010, 02:25:54 AM

Thanks Cosmos. Had no idea about the "Ricoh", which I guess is a chip. I'll investigate.

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Steady on October 08, 2010, 02:28:23 AM

@Cosmos

Is this Ricoh chip at U178 or a different one?

Title: Re: Amiga 4000/40 Hep Needed - No Display
Post by: Fingers on October 08, 2010, 02:36:31 AM

Did you check the fuse on the RGB port?

PZ.