Compaq Portable - Motherboard layout

[PhilipA]

I'm in the middle of replacing all the line filter tantalum caps on my Compaq Portable, the board is pretty heavily populated (barring a couple of unfitted ROM sockets along from the BIOS).

There's a little cluster of un-populated component locations up in the top corner by the speaker header, with some resistors and an item that has a standard 16-pin DIP layout marked K1. Anybody know what the purpose of this and the missing header J109 is?

Phil

 

[SomeGuy]

I've read that that was for a cassette interface, but was never actually used and the Compaq BIOS did not support it.

 

[PhilipA]

That makes sense.

I could see it working on a portable device, but it's also fairly pointless for one. However, the board would be well suited to adaptation as a desktop machine, so that's possibly why it's there and un-populated.

Phil