No -12v and -5V fluctuates.

5 posts / 0 new
Last post
Offline
Last seen: 1 week 3 days ago
Joined: Sep 4 2020 - 01:32
Posts: 7
No -12v and -5V fluctuates.
AttachmentSize
Image icon Aztec powersupply 19791.87 MB

I am working on an AppleII + power Suply that is universal. And I don't have -12v. I replaced all the electrolytic Caps in the secondary section with no joy. Hs anybody worked on this problem in the past. I have a schematic, not sure if it is the right schematic butit is for  Aztec and it is euro. It says IIe so it is a more modern design than mine as I don't have Riffa caps in there. 

Offline
Last seen: 6 days 1 hour ago
Joined: Sep 16 2009 - 18:34
Posts: 28
No -12v and -5V fluctuates.

I have never rebuilt a power supply, but I did send my Apple IIe power supply off for a rebuild with modern components. I used ReActiveMicro to rebuild it, and it works great. Here's a link to their power supply page on their website. Perhaps they can help with parts, and you can even contact Henry at ReActiveMicro for some pointers. His email replies take a day ot two at a minimum.

 

https://www.reactivemicro.com/product-category/power_supply/

 

Hope that helps in some way!

 

Joe

Offline
Last seen: 7 hours 1 min ago
Joined: Mar 31 2020 - 19:55
Posts: 532
gottj wrote:I have never
gottj wrote:

I have never rebuilt a power supply, but I did send my Apple IIe power supply off for a rebuild with modern components. I used ReActiveMicro to rebuild it, and it works great. Here's a link to their power supply page on their website. Perhaps they can help with parts, and you can even contact Henry at ReActiveMicro for some pointers. His email replies take a day ot two at a minimum.

 

+1 on the ReActive rebuild boards. 

Offline
Last seen: 7 hours 5 sec ago
Joined: Jun 16 2020 - 16:58
Posts: 166
Disclaimer: there are

Disclaimer: there are potentially lethal voltages in a PSU so I do not recommend you working on it and if you do you do so at your own risk.

 

When it comes to electronics I am a tinkerer but those PSUs are ery basic in construction and I believe the principle of operations is the same between them.

 

If you get +12V and +5V, you can assume the primary side is working. Did you try checking for shorts on the secondary side?

 

I found this, can you find your PSU in it? ftp://ftp.apple.asimov.net/pub/apple_II/documentation/hardware/schematics/Astec_Power_Supplies_Aug82.pdf

 

 

Online
Last seen: 8 min 50 sec ago
Joined: Jun 6 2020 - 10:50
Posts: 58
It may just be the picture,

It may just be the picture, but Z1 (presumably a zener diode) in the lower left of the picture looks a little crispy.  Does that part look OK in person?

 

Log in or register to post comments