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Re: Small audio mod?

Posted: 19 Jun 2021 10:08
by exxos
I suggest you desolder the cap to see where the tracks go then you can see if there is anywhere to solder to..

Re: Small audio mod?

Posted: 19 Jun 2021 13:34
by DoG
Darklord wrote: 18 Jun 2021 21:42...
Can someone more experienced please draw an arrow pointing directly
(and exactly) to the one I'm supposed to solder the + wire from an RCA
jack to?
I think this info will suffice for you? Pink/Purple is the audio out on the monitor port and thus + on the audio jack. Ground can be taken from whatever but I pointed out one next to the audio out for you.

EDIT: I watched your photos again and you seem to have less ground vias then my board so I added some more blue dots on the pics below to indicate where to pick that up.



MegaST audio out motherboard.jpg
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MegaST audio out motherboard back.jpg
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Re: Small audio mod?

Posted: 19 Jun 2021 14:49
by Darklord
Thanks! I think I'm going to go with Pin one on the monitor
socket - it looks easiest to do. Late last night I had found
a post from the early 2000's where a guy described Pin 1
close enough that even I could find it. Your post confirms
it.

As far as the ground goes, I had already run a line (with
an eyelet) to the P/S mounting leg, attaching it via the
screw that holds the P/S frame to the motherboard.
That should be okay, right?

Thanks again! :)

PS Really nice job on the pictures.

Re: Small audio mod?

Posted: 19 Jun 2021 18:08
by Darklord
Finally, with lots of help, I've got this installed. Even though it's mono,
it's a huge improvement over the monitor speaker. I've got a pair of
cheap Altec-Lansing speakers set up with it and it still sounds soooo
much better.

Thanks to everyone who pitched in, appreciated! :)

Mega ST4 Audio Mod01.jpg
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Mega ST4 Audio Mod02.jpg
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Mega ST4 Audio Mod03.jpg
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Mega ST4 Audio Mod04.jpg
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Re: Small audio mod?

Posted: 20 Jun 2021 09:49
by sporniket
nicely done. Good solderless trick for the wire to ground.

Re: Small audio mod?

Posted: 20 Jun 2021 22:42
by Darklord
Thanks! I'm really pleased with the results. Even the cheap speakers
I hung off of it sound great with some classic MODs cranked up.

I've been cranking:

Axel-F
Stardust
Xenophobe
Quantum
Cortouchka
Guitarious
Thrash
Crazy Train

Etc, etc,... :)

Thanks again to everyone involved and all the help, appreciated!