DTK PKM-0033S motherboard restoration \ VOGONS

DTK PKM-0033S motherboard restoration

Topic actions

Post a reply

First post, by alexthekid

Posted on 2020-10-05, 19:54

alexthekid Offline

Rank Newbie

Rank: Newbie
Posts: 35
Joined: 2020-09-23, 09:05

Hi everyone,

I recently got a PKM-0033S motherboard.
It has a corrosion-by-leaked-battery problem.
I have already fixed all the corroded tracks but there are 2 damaged resistors near the battery R71 and R89 (the picture was taken before any repairs were done):

On R89 the resisistive layer is completely gone. On R71 it is gone on both edges. Measurement gives me open loop (>200MegOhms) for both resistors.

Can anbody here with a PKM-0033S give me the resistance values of R89 and R71?
Thank you 😀.

Reply 1 of 5, by alexthekid

Posted on 2020-10-08, 12:21

alexthekid Offline

Rank Newbie

Rank: Newbie
Posts: 35
Joined: 2020-09-23, 09:05

I figured R71 out myself 😀. R71 is 4.7kOhms. No luck on R89 yet. It seems that R89 is connected to the AT-power good signal, which turns from 0V to +5V as soon as the power is good ... so maybe R89 is just a pullup-resistor?

Reply 2 of 5, by ninjabuffy

Posted on 2021-08-02, 07:00

ninjabuffy Offline

Rank Newbie

Rank: Newbie
Posts: 3
Joined: 2021-08-02, 06:58

alexthekid wrote on 2020-10-08, 12:21:

I figured R71 out myself 😀. R71 is 4.7kOhms. No luck on R89 yet. It seems that R89 is connected to the AT-power good signal, which turns from 0V to +5V as soon as the power is good ... so maybe R89 is just a pullup-resistor?

Did you ever find out the value of R89? I have the same issue after the barrel battery leaked.

Reply 3 of 5, by watson

Posted on 2021-08-03, 13:13

watson Offline

Rank Member

Rank: Member
Posts: 100
Joined: 2018-01-05, 12:36

Here is a photo of the area I found in an online auction for the purpose of repairing my board.

R89 seems to be 000, i.e. a zero-ohm link.

My board is in much worse condition, the two Winbond chips are completely corroded (W83768F and W83787F), but the board still seems to work fine with an external floppy/IDE controller card.
Also, could you tell me the value of R28? It is missing on my board and it is partially obscured by the capacitor in the photo. I am not sure how much it actually matters, though.

Reply 4 of 5, by ninjabuffy

Posted on 2021-08-03, 17:44

ninjabuffy Offline

Rank Newbie

Rank: Newbie
Posts: 3
Joined: 2021-08-02, 06:58

Thanks! R28 seems to be 1K ohm.
These batteries are nasty, glad you got it to work using external I/O controller.

Attachments

Filename

IMG_20210803_193949~2.jpg

File size

193.02 KiB

Views

373 views

File license

Fair use/fair dealing exception

Reply 5 of 5, by ninjabuffy

Posted on 2021-08-04, 14:07

ninjabuffy Offline

Rank Newbie

Rank: Newbie
Posts: 3
Joined: 2021-08-02, 06:58

It is working now 😀

Go to top of page Go to top of page

Back to General Old Hardware

Main menu

Common searches