I am trying to get into diagnosing and fixing electronics. I was brought a brother intellifax 770 fax machine by someone which does not turn on. My first thought is something with the input power then. Open it to find a blown 125V4A fuse. Replace fuse, and it blows again immediately. What is my next step now in analysis? I was thinking to look for a broken rectifier or transformer if those even can break. Would i need to email the company for a schematic? Does that work? I realize these are many questions google can answer, but I value this website and wish to become more involved.

 

Instafail usually points to the power supply. In today's world, probably a high speed switching supply. First step is a schematic. Asking the manufacturer is a good option.
This might help:http://www.servicesoftware.com/sams.asp

 

Thank you very much. I had already emailed the manufacturer. The machine has to be at least 8 to 10 years old. Brand doesn't seem to be on list. I will wait for an email response as I have a fear of shorting the supply. For future reference, is there a better place to post for electronics repair than general chat?

 

You are in the right place for this website. Part of the process is waiting for a person that wants to try to fix a fax over the internet. Personally, I don't do fax machines. This site has people all over the planet and some of them are asleep right now.

 

Try disconnecting the power supply from the boards it is supplying voltage to.

If the fuse doesn't blow then the power supply is OK Next, begin reconnecting the boards (one at a time)till you find the board which is causing the problem.

 

First step would be to take clear close up pictures of the power supply & post, rather than guessing at what is being repaired.