VOGONS


First post, by henryVK

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Okay, dear Vogons,
several things are going on with my Siemens PCD-4ND that I would love to hear some opinions on.

The laptop has an ISA ESS1688 and a tiny 0.4W speaker and no external volume knob or wheel. The last two facts have bothered me somewhat ever since I got it, so I've been thinking about replacing the speaker. It sound quite tinny, especially with increasing volume, which may be simply due to its size and output or, not unlikely given its age, a damaged membrane.

I've been wondering what would happen if I replaced the speaker with a slightly larger one, say, 1-2W. Could this work, or is the sound cards amplifier (and the laptops ac-unit) likely to be incapable of dealing with higher output speakers? It would also be incredibly practical to install ("case mod") a volume control of some sort. However, I understand that it is somewhat unorthodox to just put a pot between speaker and amp. Is this feasible at all?

Now, the simple workaround here would of course be just to hook up external speakers to the headphone jack and use those instead, however, the headphone jack also has an issue, in that it is giving out really loud static. I've cleaned the jack with isopropyl but dirt doesn't seem to have been the problem. I have yet to disassemble the sound unit and check the soldering/shielding, which I guess that's the next obvious thing to check, unless someone can point me to another potential solution for this issue.

Anyway, I would be grateful for any and all advice, even if it is not to mess with this one 😀
I do like the machine as it's lightweight and perfect for playing 486-era stuff on the couch.

Best regards
Henry

Reply 1 of 2, by henryVK

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Okay, so I was unable to remove the Sound Module for now. It wouldn't budge and probably requires further disassembly. It's pretty clear, however, that the jacks are soldered right to the board, so no unshielded cables, and the solder looks insuspicious. I'm guessing that the problem could be either the jack itself or down the signal path.

Reply 2 of 2, by henryVK

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Well, good news. I replaced the old speaker with a similar one, for now. The old one was 0.4W, the new one is 0.5W. I'm still wondering if a better speaker would work, or if the increased draw would fry the board.

What I did to improve matters is to encase the little speaker in a styrofoam "housing" to keep it from vibrating against the case and creating that "tinny" sound. I'll add a trimmer style pot to adjust the volume, and if that pans out, I'll make a little slot for it in the laptop case.

Thankfully the Siemens engineers designed the PCD-4ND with the speaker right underneath the keyboard cover which pops open after removing the screen assembly (3 screws) and 10 or so screws. Very convenient and tidy!