Is there any marking on U10 IC?

I'd say it looks like a VGA capture card, or something similar. It doesnt look like a sound card to me...

Definitely not a VGA or capture card, the needed components just aren't there. It looks like an adlib clone with a nonstandard game port. The big chip is probably an OPL2.

any FCC ID sticker on the back?

I think its a Sound Blaster clone of some sort, its too complex to be merely an adlib clone, and I see IRQ jumpers down near the ISA connector.
I think the D-Sub connector is possibly a MIDI port.

I really don't think its a video or capture card of any description. On ISA video cards you usually see crystals to sync with the video frequencies and there's no video memory on it. Most of the chips on the board are just TTL logic chips or op-amps, not complex enough for a video adapter.

9235 is manufacture date, 35th week of 1992. But why 8-bit?

P.S. Maybe, FM radio? The plug on the top might be for antenna.

Or it can be oscilloscope main board. But maybe not...

Could you take more images? One straight from the top and back. And also looking at the connectors.

The card seems to contain building blocks for an Adlib clone (UA010=OPL2, UA011=DAC, LM324=op-amp, LM386=speaker amp, backpanel has volume pot and audio output connector).

It also has seems to have a joystick interface (NE558 and pinheader for external DA-15 joystick connector).

It definitely has something to do with video as well. Maybe it takes in DE-15 VGA and outputs composite PAL video on RCA (the crystal reads 4.433619 which is a PAL color subcarrier frequency).

Most definitely it is not a SoundBlaster clone just because it has interrupt jumpers. The original Adlib card also had provisions for jumper selectable IRQ, but the pinheader for jumper was not mounted, so no interrupt could be selected unless a pinheader was soldered and a jumper placed there. Here the pinheader is mounted but no jumper so no IRQ is selected.

I do not believe it has MIDI port, simply no component would do it, if U10 converts video.

Jepael wrote:

The card seems to contain building blocks for an Adlib clone (UA010=OPL2, UA011=DAC, LM324=op-amp, LM386=speaker amp, backpanel […]
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The card seems to contain building blocks for an Adlib clone (UA010=OPL2, UA011=DAC, LM324=op-amp, LM386=speaker amp, backpanel has volume pot and audio output connector).

It also has seems to have a joystick interface (NE558 and pinheader for external DA-15 joystick connector).

It definitely has something to do with video as well. Maybe it takes in DE-15 VGA and outputs composite PAL video on RCA (the crystal reads 4.433619 which is a PAL color subcarrier frequency).

Most definitely it is not a SoundBlaster clone just because it has interrupt jumpers. The original Adlib card also had provisions for jumper selectable IRQ, but the pinheader for jumper was not mounted, so no interrupt could be selected unless a pinheader was soldered and a jumper placed there. Here the pinheader is mounted but no jumper so no IRQ is selected.

I do not believe it has MIDI port, simply no component would do it, if U10 converts video.

that's actually a 9 pin connector. in the 8 bit world, a 9 pin connector was "usually" a CGA monitor connector. Serial ports tended to be 25 pins at the time. "tended"

I would wager a guess, it is an ad-lib clone but with a CGA -> composite video converter. In theory, its just a simple DAC to go from cga to composite. It would make sense, if you are converting a tv to a monitor, that you would also have sound.

stbunny wrote:

Is there any marking on U10 IC?

No markings. They were removed.

elfuego wrote:

I'd say it looks like a VGA capture card, or something similar. It doesnt look like a sound card to me...

Adlib is working in DOS games, so it's partially a sound card and it has a game port connector on top left, i have the cable.

Anonymous Coward wrote:

Definitely not a VGA or capture card, the needed components just aren't there. It looks like an adlib clone with a nonstandard game port. The big chip is probably an OPL2.

The port is VGA, and i have the cable too. I can connect it to a VGA card and it outputs normal image.

TheMAN wrote:

any FCC ID sticker on the back?

No sticker on the back unfortunately.

More pics tomorrow.

U10 might then be a Sony CXA1645 or similar RGB encoder chip to convert VGA into PAL composite video in this case - seems like this card packs a bunch of stuff to sort of turn a PC into a games console (sound, joysticks, TV output). Very interesting I must say!

One thing I can't explain is what does it do about the horizontal scan rate since standard TVs won't like anything over 15 kHz. I know there are some TSRs for reprogramming certain VGA cards into outputting 15 kHz video, my guess is that this card may have come with one of those. The fact that the crystal oscillator is for PAL color makes it even more strange because of PAL's 50 Hz frame rate.

You could use it and dump its BIOS.

I don't see anything resembling a ROM BIOS on the card.

Agree, definitely no ROM bios on that card.

And it seems the U10 might really be an CXA1645 (or clone) as suggested, based on pinout (pins 1 and 24 are ground, 6 is for colorburst crystal), but pics from the bottom side of the card are needed to verify this any further.

More pics as promised.

Some sort of MPEG decoder board?

I think we have a pretty good idea of what it is (adlib + game port + vga-->composite converter). The big question is what the purpose of it all is. For something supposedly made in 1992, why would it not have a DAC? It was suggested by another poster that it might be to convert a PC into an arcade machine. That's the only logical conclusion I've been able to come to as well.

The "9235" seems just a little bit too prominent.

Googling turns up something called a "Videk 9235" that is referred to as a video splitter, but provides no further details.