Hi, welcome to the forums! 😀

The schematic at Wikipedia is very basic (on purpose).
Maybe adding one or two capacitors (aka condensers) will make the signal softer and cleaner.
Don't worry, the values aren't that important here.

Here's an example how to place them in your circuit (pin20=gnd):
https://www.msx.org/wiki/Covox

Also have a look at the Covox thread.
While it's not a generic thread about Covox, it contains some valuable information.

By the way, I'm using a Compaq, too. It's a Contura 400. 😁

Best regards, Jo22

kemi242 wrote:

Hi all! […]
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Hi all!

I have just finished building a Covox plug (I have used the schematics provided on Wikipedia). I have double checked the circuit, it looks fine according to the schematics, however it produces a crap ton of static hiss with everything I tried. I have tried some games, and Inertia Player. Could be something wrong with my circuit, or is there a specific BIOS setting for the parallel port?
BTW, I'm using a Compaq Armada M700 laptop.
Thank you!

Hi and welcome.

If you could take a sharp high-res photo (or maybe more) of your plug so I can take a look at it?
Preferably ones that shows all data and ground connections and resistors.
(I left my crystal ball at the polisher's so I can't work without a photo... 😀 )

Cheers!

Hello All,

I've just finished building the version suggested by Jo22. It works pretty fine, I'm very surprised how good it sounds, because I couldn't get the right resistor values. Maybe I messed something up with the first try.

Thanks for the help.