Compaq Portable III RF Shield

[schenkzoola]

One of my many projects is a Compaq Portable III. I'm currently reassembling it after a thorough cleaning.

There is a cardboard RF shield around the video controller and the modem/ram expansion area. On my copy this has deteriorated due to moisture exposure.

Is this a piece that can be safely left out, or should I try to craft a replacement? It might be possible to fix this one up a bit with some careful cleaning and ironing.

I've attached a photo to show which shield I'm talking about.

Thanks!

 

[modem7]

Is this a piece that can be safely left out, ...

I think the shielding is present to:

1. To reduce interference between various parts of the computer; or
2. To reduce interference generated by the computer as a whole (e.g. meet an FCC RFI requirement); or
3. Both of the above.

Re point 1. I think that will be a 'suck it and see' thing. In the day, we would not be expecting customers to see if there is a problem, but things are different in a hobby environment.

Re point 2. Interference to TV/radio reception, etc? Probably less of an issue these days.

 

[schenkzoola]

Thanks for the reply modem7.

The shield looks like an afterthought, which makes me think it was installed for EMI/RFI reasons. In the US, commercially manufactured computers do require FCC emissions testing.

During the New Years break, I'm going to try to clean up, flatten, and reinstall the shield. If that fails, I'll just leave it out. I'll update this thread with my results.