Jump to content

Recommended Posts

I'm considering buying a BBC model B and I've seen a few with blown PSUs (common problem).  My question is, assuming the machine was ok to start with, what are the chances of it being ok if the PSU is fixed?  Will 90% survive or will there be a good chance that the PSU has taken some other components with it?

 

 

Share this post


Link to post
Share on other sites

After doing some more searching I found an article saying the caps are for noise surpression and probably won't cause any problems after a pop but obviously should be replaced.  If anyone has a different view on the subject I'd be happy if you posted.

Share this post


Link to post
Share on other sites

My bbc b blew when powered up for the first time in 20 years, no damage occurred to the bbc and I bought a cap kit to fix up the PSu. It’s been running for hours on end for the last 4 or 5 years now. 
 

 

  • Like 1

Share this post


Link to post
Share on other sites

I believe there are a couple ways a BBC PSU can blow. Some just emit the filter smoke without affecting functionality, some won't power on. I've repaired one and replaced one out of the four I've owned in recent years. There doesn't seem to be a case of overvoltage so the motherboard should be fine even if the PSU died.

  • Like 1

Share this post


Link to post
Share on other sites

I just picked up a really nice looking BBC B for £40 (+£10 postage) which was working ok for 10mins before psu blew.  Ordered a cap kit for £4 so I if my soldering is up to the task I think I got a nice buy :)

 

 

Share this post


Link to post
Share on other sites

I believe the hardest is to desolder the blown components cleanly. Installing the new ones and securing with solder is obviously an easier task.

Share this post


Link to post
Share on other sites
Posted (edited)

I finally got round to doing this.  Having never soldered before I was a bit worried but it was fairly simple process.  Desoldering was a bit awkward, probably due to a low iron temp (RMC kept his low in the vid I watched) but soldering the new caps was simple enough.

 

The hardest part was dismantling the psu and getting the board out of it, removing the power switch took me forever lol

 

Anyway, it's working fine now and looking great.  I also got a data recorder with it (and a wordwise rom was installed) that I don't need so I'll flip that on ebay, with the stupid prices some of those go for I could end up with a free computer :)

 

Thought I'd show u a pic, all I've done is give it a quick wipe with windolene and gave the keyboard a little brush - the guy selling it obviously didn't know about the common psu problem and probably thought it was a gonna.

 

20210702_130911.jpg

Edited by Preppie
  • Like 2

Share this post


Link to post
Share on other sites

Hard to say, probably took me a couple of hours but it's the first time I've done anything like this so I was being extra careful.  If I was to do it again I could do it in 30mins I guess.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...