Problem with HP 25

[krazyk]

Woo Hoo

After carefully dissassembly, the blue green corrosion from the battery pack was easily visible on the keyboard assembly PCB. I then applied the DeOxit 100% RED solution to all of the large VIA holes under each button using the foam coated toothpick they supply in their kit. I then used a resistor lead with a small L shaped kink in one end and ran that around each of the VIAs to encourage the DeOxit to do its work and to mechanically scratch away the corrosion under the inacessible key bubbles.Be careful though and do not push too hard, just gentle abrasion.

It is obvious why 4 and 5 were the worst effected as they are the closest to the NiCad battery pack terminals. It had also attacked some of the RAM and ACT legs but that was easily rubbed away.

   

I waited for a few hours and then reassembled the HP 25 which is a little annoyingly difficult for the first time.

   

4 and 5 needed a LOT of excercising but eventually they started reacting to my enormous relief. I hope the Deoxit may continue to work over the next day or 2 as the 4 in particular needs a FIRM click to register.

This has been very satisfying and the build quality of this device is fantastic. They dont make them like they used to thats for sure. I can see why you guys love resurrecting as many of these 1970s HP units.

Hmmmmm....... now to find another unit....... :-)