Jump to content
IGNORED

ATR 8000 Repair


scitari

Recommended Posts

How do you know it's not powering on?  Have you tested voltages anywhere or are you just going by the light in the power switch?  Hard to be sure from the pic, but check the solder on the diodes next to the power connector block. Looks like there might be cracks.

 

Would love to get a dump of that EPROM  if you have the means.

Edited by JR>
  • Like 3
Link to comment
Share on other sites

28 minutes ago, JR> said:

How do you know it's not powering on?  Have you tested voltages anywhere or are you just going by the light in the power switch?  Hard to be sure from the pic, but check the solder on the diodes next to the power connector block. Looks like there might be cracks.

 

Would love to get a dump of that EPROM  if you have the means.

No light. No hum. I do plan to check all the contacts. Am curious if anyone has actually replaced a PSU in one of these. Thanks!

Link to comment
Share on other sites

8 minutes ago, scitari said:

No light. No hum. I do plan to check all the contacts. Am curious if anyone has actually replaced a PSU in one of these. Thanks!

The problem is probably limited to something between the wall outlet and transformer then.  Most of the "power supply" is built in to the motherboard.  There's really only the transformer, switch, power cord and socket that aren't part of the MB.

Link to comment
Share on other sites

The power supply circuit isn't unusual, other than the transformer not being external it is similar to the 1050 power supply circuit, the main difference is the use of a 14V center tap transformer(no voltage doubler circuit required for +12VDC). It has 2-7805 voltage regulators with, and 1-7812 without, heatsinks. The light color TO220 chip furthest from the transformer is a TIP30 used to generate -5V/-12V, most likely for the RS232 interface.

The power supply schematics I found at archive.org show an RFI filter, 3/4A fuse, switch and MOV between power and the transformer.

https://ia801604.us.archive.org/1/items/atr8000/ATR8K4.pdf

Manuals/rest of the schematics are there as well.

https://archive.org/details/atr8000

  • Like 3
Link to comment
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...