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Question About Changing Dreamcast Optics and Modem

Posted: Sat Feb 22, 2020 1:02 pm
by thedemon1238
Hello dreamcast players! :mrgreen:

I want to ask two questions about dreamcast hardware compatibility.

1. Can I use Dreamcast pal modem HKT-3030 (670-14116A) with japaness dreamcast console that don't have modem (HKT-3010)? For playing online.

2. Can I switch Dreamcast GD-ROM drives, from PAL dreamcast to japanese and vice versa? Will they work?

Re: Question About Changing Dreamcast Optics and Modem

Posted: Mon Feb 24, 2020 12:11 pm
by Alex_DC
I can answer question 2 with certainty; the drives are NOT region locked.

As for 1 - I have mixed and matched a lot of Dreamcast parts on my own machines, never had an issue with the modem causing the machine not to boot, BUT, I have never tried to take these Frankenstein Dreamcasts online.

Re: Question About Changing Dreamcast Optics and Modem

Posted: Tue Feb 25, 2020 11:49 am
by Caspian
I once placed a NTSC-US GD-ROM to a PAL Dreamcast and it worked fine.

Re: Question About Changing Dreamcast Optics and Modem

Posted: Wed Feb 26, 2020 6:52 am
by NightBreeze
Japanese modem works on my PAL Dreamcast (even online), so I don't see a reason why it shouldn't work the other way around. But remember, PAL modem requires 18V, not 9V like US/Japan modems.

Re: Question About Changing Dreamcast Optics and Modem

Posted: Wed Feb 26, 2020 8:28 am
by pipporamone
2. Can I switch Dreamcast GD-ROM drives, from PAL dreamcast to japanese and vice versa? Will they work?

Depends, they need to be same voltage 5v or 3.3v

Re: Question About Changing Dreamcast Optics and Modem

Posted: Wed Feb 26, 2020 12:45 pm
by megavolt85
pipporamone wrote:Depends, they need to be same voltage 5v or 3.3v
you are mistaken

Re: Question About Changing Dreamcast Optics and Modem

Posted: Thu Feb 27, 2020 5:33 am
by pipporamone
Early japanese units have a 5 volt GD-ROM (written on plate). it is not recommended to put that on a DC board with a 3.3 v GDROM (works but behaves strangely, tested)

You can indeed switch the lens (works, tested personally)

95% of Dreamcast i have seen have 3.3v GD Rom so these are interchangeable.

Modems:

NTSC-u have 56k 9v
90% of NTSC-J are 33k 9v (late model are 56k 9v).
PAL modems are 33k 18v.

if you go online i suggest to take a north american modem.

Hope this will clarify

Re: Question About Changing Dreamcast Optics and Modem

Posted: Thu Feb 27, 2020 6:45 am
by Anonymouse
pipporamone wrote:
if you go online i suggest to take a north american modem.

Hope this will clarify
I assume he will be using it with DreamPi so it doesn't matter which model he uses as the download/upload will be limited to 33.3Kbps anyways. Its only the line voltage that needs to be considered.

Re: Question About Changing Dreamcast Optics and Modem

Posted: Thu Feb 27, 2020 6:57 am
by pipporamone
Anonymouse wrote:
pipporamone wrote:
if you go online i suggest to take a north american modem.

Hope this will clarify
I assume he will be using it with DreamPi so it doesn't matter which model he uses as the download/upload will be limited to 33.3Kbps anyways. Its only the line voltage that needs to be considered.

That's true...only if you use alternative method (like standard dial-up) games like quake 3 will benefit with a 56k.

Re: Question About Changing Dreamcast Optics and Modem

Posted: Thu Feb 27, 2020 7:19 am
by megavolt85
pipporamone wrote:Early japanese units have a 5 volt GD-ROM (written on plate). it is not recommended to put that on a DC board with a 3.3 v GDROM (works but behaves strangely, tested)
5v GD-ROM fine work on 3v3 board, 3v3 GD-ROM fine work on 5v board

GD-ROM use ATA controller from PC CD-ROM and compatibily with both voltages