Mac SE FSHD black screen + loud noise

[billbucks060]

Hi,
I bought an old Mac SE FDHD (model 5011) which I'm trying to fix and bring back to life.
When I start the Mac, the screen remains black/off and there's a loud noise inside.

I opened the case and I took the following photos.
I removed the card attached to the screen and it look ok.

Any idea ?

https://imgur.com/r5PmN8a

https://imgur.com/dnrSayb

 

[DistantStar001]

The last time I saw something like that was on my Commodore PET. The stem of the CRT had been broken off just past the neck board.

View attachment PET Sparks.mov
If the sound you hear is similar to the sound in the video, it's likely be electrical arching inside the machine. Unfortunately, it means that you will need a new CRT. :-(

 

[thellmer]

If that is a blue glow inside the neck of the CRT then yes, your CRT is broken and arcing inside. Hard to tell if its actually a blue arc in the picture tube or just blue from the camera lighting though.

 

[LaPorta]

The CRT neck is visibly displaced laterally, so yes, it is done and you need another.

 

[billbucks060]

This is indeed the case, there's a blue glow inside the neck of the CRT with a sound similar to the video.
I can use this Mac for parts I'm afraid.

I got 2 old Mac SE, both have M5011 written at the back, the only difference being one has FHDH written on the front case.
With the FDHD CRT broken, is it worth trying to replace it with the one from the other Mac as it seems to have better specs, or just move RAM, floppy, and HD to the working Mac?

 

[billbucks060]

Hi,
I ended up building a new machine swaping the motherboard, adding some RAM to have a single good working Mac SE.
I will try to sell what remains from the other one for parts (CRT is dead).

 

[billbucks060]

Just a thought ; is it the CRT which is broken or could it be the card that is attached into the back of the CRT that needs fixing ?

 

[DistantStar001]

Sadly no. The neck card is low voltage. That kind of arching is caused when the CRT no longer keeps a vacuum.