Sherry Haibara
Well-known member
Hello!
As this is my first post here, let me say that I'm very delighted to have found such a wonderful community of people who still cares about our beloved, ancient Macs. I think it's a really helpful place, it has already saved me quite a lot of time!
Next, I'll move on to the problem that's puzzling me.
I recently bought a "working" (so it was said) Macintosh Plus with 4 mb of RAM, dated 1987. The system came in a somewhat disappointing shape, but I managed to clean it up to a good looking state.
I borrowed a keyboard, a mouse and a startup disk from a friend of mine who also has got a Mac Plus and I tried to power it on (I should note that it's an american 110V build, which I plugged in to the power outlet via a 220V -> 110V power adaptor).
I noticed immediately that something wasn't quite right - the screen buzzed and the Mac refused to boot, so I slapped gently on the side and it came up with the nice happy Mac; so I thought that there could be some loose connection somewhere.
I went on using it for about 15 minutes, enough to check that everything was working (I was trying to connect with the external HD drive) when suddenly the screen went black with a trembling spark in the middle and a very strange noise, like a "blip blip" that kept going on.
I immediately unplugged the power cord and let it rest for some minutes before plugging it back in - this time to see the screen completely black, and the very annoying "blip blip" sound coming from inside the machine.
I did some research on this forum, and there seems to be a few options about what might be happening here:
- blown up diode: the main suspect here seems to be the CR20 diode, which I read fails quite often in the american version of the plus
- dead capacitors somewhere, possibly in the power supply?
- cracked solders
I tend to see the last one as the more likely, since I read in this topic that another user seems to have had the same problem and fixed it with reflowing some loose connections. But I'm not quite sure yet, so I thought it would be wiser to hear your opinion on this matter.
It may help to know that the "blip blip" noise is not coming from the floppy drive, but is clearly an electrical sound coming from somewhere deep inside the case.
I still haven't opened the Mac (I don't have the right torx 15 screwdriver yet) so I don't know the status of the board, I'm trying to come up with a diagnosis to know where to look and what to pay attention to.
As an attachment to this post I uploaded a recording of the "blip" noise so that you can have a better idea of what's actually happening here.
Thanks in advance for all the help!
Cheers
Sherry Haibara
As this is my first post here, let me say that I'm very delighted to have found such a wonderful community of people who still cares about our beloved, ancient Macs. I think it's a really helpful place, it has already saved me quite a lot of time!
Next, I'll move on to the problem that's puzzling me.
I recently bought a "working" (so it was said) Macintosh Plus with 4 mb of RAM, dated 1987. The system came in a somewhat disappointing shape, but I managed to clean it up to a good looking state.
I borrowed a keyboard, a mouse and a startup disk from a friend of mine who also has got a Mac Plus and I tried to power it on (I should note that it's an american 110V build, which I plugged in to the power outlet via a 220V -> 110V power adaptor).
I noticed immediately that something wasn't quite right - the screen buzzed and the Mac refused to boot, so I slapped gently on the side and it came up with the nice happy Mac; so I thought that there could be some loose connection somewhere.
I went on using it for about 15 minutes, enough to check that everything was working (I was trying to connect with the external HD drive) when suddenly the screen went black with a trembling spark in the middle and a very strange noise, like a "blip blip" that kept going on.
I immediately unplugged the power cord and let it rest for some minutes before plugging it back in - this time to see the screen completely black, and the very annoying "blip blip" sound coming from inside the machine.
I did some research on this forum, and there seems to be a few options about what might be happening here:
- blown up diode: the main suspect here seems to be the CR20 diode, which I read fails quite often in the american version of the plus
- dead capacitors somewhere, possibly in the power supply?
- cracked solders
I tend to see the last one as the more likely, since I read in this topic that another user seems to have had the same problem and fixed it with reflowing some loose connections. But I'm not quite sure yet, so I thought it would be wiser to hear your opinion on this matter.
It may help to know that the "blip blip" noise is not coming from the floppy drive, but is clearly an electrical sound coming from somewhere deep inside the case.
I still haven't opened the Mac (I don't have the right torx 15 screwdriver yet) so I don't know the status of the board, I'm trying to come up with a diagnosis to know where to look and what to pay attention to.
As an attachment to this post I uploaded a recording of the "blip" noise so that you can have a better idea of what's actually happening here.
Thanks in advance for all the help!
Cheers
Sherry Haibara