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Need help determining best portable+CGA+808x for modern air travel

Trixter

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This post is a little weird -- bear with me.

I'm going to a demoparty in June where I plan to enter a demo running on an 808x with CGA, output to a projector so everyone can see it large. I did the same thing last year, achieved by shipping a PCjr via the USPS back and forth to the partyplace, but this year's entry needs a sound card so I can't do the PCjr again; I'm considering what other options exist for bringing a portable/luggable with me on the plane. I have a 5155, but according to United's new baggage size rules, it's dimensions are too large to bring on the plane (it might fit as-is but I would be wrapping it in bubble wrap. I also have two Panasonic Sr. Partners but they are very fragile and temperamental so I won't want to bring those. Even though it's a 286, I would love to bring my Compaq Portable III, but it doesn't have composite CGA output, only TTL RGB (not sure how I'd hook that up to a projector).

I'm not beyond trying to acquire something new that would be appropriate, but it has to accept two ISA cards, one for a Sound Blaster and another for an XTIDE variant. Doesn't need a built-in monitor, although if it does, it doesn't have to be a glass CRT. Any ideas, or should I resign myself to shipping a system back and forth again? Is it possible to convert CGA's TTL RGBI to something (composite, etc.) a projector can display?
 
Does it have to be an 8088-class machine, or can it be a 286/386 class machine?

If the latter, you might want to look around for some Dolch luggables, built for industrial use, typically as network sniffers. They're usually pretty expensive on eBay (desireable for their Cherry switch keyboards), but they can be had in the ~$150 range (or less if you're lucky). They can accommodate most ISA cards without trouble, so you should be able to pop a CGA card in there without problems. They're also smaller than the Compaq III and will likely work as carry-ons

I can get you dimensions of mine if you want. It's a Dolch PAC-64, IIRC with a 200mhz processor and built-in VGA. I got it for $80 shipped, originally purchased for the keyboard, but after playing with it, I couldn't bear to cannibalize it.
 
The solution is obviously to build a sound card for the peanut! I'll get right on it.

Also you could do a 8088 ISA SBC with a passive backplane like Sergey's. It would allow you to break it down to individual cards and store it anyway you like for travel. Take an PicoPSU with you for ease of power.
 
I suppose a Disney Sound Source or Covox device is out of the question, otherwise you could use it. I think MediaVision implemented its Thunderboard on a parallel dongle, but the programming would be quite different from a real Sound Blaster.

A Tandy 1000 is generally smaller than a IBM PC Portable, maybe it will fit within the regulations.
 
All the 8088 CGA portables (that aren't huge) with composite I can think of have a proprietary expansion bus, like the Toshiba T1200 etc. CGA composite outputs are quite often monochrome too (well on the machines I've used they were - someone correct me if that's not accurate).

You could consider investing in a half decent CGA->VGA converter - I've been considering this myself, just really hard with their pricing sometimes :/

Only portables (suitable to go on a plane without wrapping) I have with ISA are 386+VGA - Toshiba T3200SX/T5200 etc
 
Don't planes allow one computer/computer bag that doesn't count as luggage? :) Could you add a composite video card to the Portable II? Seems like a good system to take. I'm not 100% sure what other systems you have but there are also small form factor XT clones out there too I think but that might require buying and figuring out what they are. What about your 6300? Pretty rugged.
 
Shame you need a sound card, I'd think along the lines of something like my sharp PC-7000... though that also lacks a CGA output without the option board (which I don't have either)...

How complex do you need for a 'sound card'? Could you squeak by on something like a Covox or Disney Sound Source? (something I'm adding a simple 4 voice synth support for to my current library)
 
Would a Compaq Portable work? The original one does CGA and can support a sound card while being portable. I don't believe the video card outputs anything in 80x25 mode however, but don't quote me on that.
 
Does it have to be an 8088-class machine, or can it be a 286/386 class machine?

386 would be acceptable; anything faster than that and it wouldn't be an impressive demonstration.

The solution is obviously to build a sound card for the peanut! I'll get right on it

LOL!

I suppose a Disney Sound Source or Covox device is out of the question, otherwise you could use it. I think MediaVision implemented its Thunderboard on a parallel dongle, but the programming would be quite different from a real Sound Blaster.

I need a Sound Blaster for DMA (background) playback, so these won't work for my purposes, unfortunately.

A Tandy 1000 is generally smaller than a IBM PC Portable, maybe it will fit within the regulations.

Hm... a "slim" PC might be the only thing that is practical. Interesting; I'll see what I have in storage.

You could consider investing in a half decent CGA->VGA converter - I've been considering this myself, just really hard with their pricing sometimes :/

Those don't actually work with real IBM CGA -- they only have RGB pins whereas IBM CGA is RGBI. The output of the converter is the lower 8 colors only, and color index #6 (brown) is the wrong color (yellow).

Could you add a composite video card to the Portable II?

No, since the internal gas plasma display is driven from the onboard video.

What about your 6300? Pretty rugged.

No composite CGA output :) and they're not as rugged as you think.

(something I'm adding a simple 4 voice synth support for to my current library)

I look forward to hearing the results!
 
How about just the mobo and as suggested a picoPSU? "Here's my bag of bits from 80s and it does this..." :D
 
If you have to have a soundblaster you will need either a full PC or an Industrial chassis (PC card and an ISA backplane for the sound card). Would an IBM PS/2 model 25 work (MCGA should do CGA if they have a video out, can take an 8bit ISA card for soundblaster, not overly big).
 
Where is this? If you're going to be within a reasonable drive I'll deliver a 5155 to you when you get here. I'm sure others would do so also.

Kelly
 
As far as CGA output to a projector goes, you could use one of the CGA video DAC boards that I am making, along with a GBS-8220 arcade scaler. That combo works _very_ well for CGA output to modern monitors.

- Alex
 
Normally yes, but IIRC it has the same dimensions as my IBM 5155, so it won't fit in the overhead bin.

Its been a while since I've had hands on a 5155, but I actually remember it being SMALLER than a Compaq Portable I, but I'm a bit hazy on that, it was in the 90's when I got rid of my 5155 and Portable I (both were missing MANY bits and pieces, but in hind sight I should have kept them for parts).
 
As far as CGA output to a projector goes, you could use one of the CGA video DAC boards that I am making, along with a GBS-8220 arcade scaler. That combo works _very_ well for CGA output to modern monitors.

- Alex

There you go teasing me again... ;-) I'm anxiously awaiting ordering information so I can put in an order for one! :)

Thanks,

Wesley
 
Those don't actually work with real IBM CGA -- they only have RGB pins whereas IBM CGA is RGBI. The output of the converter is the lower 8 colors only, and color index #6 (brown) is the wrong color (yellow).
Their inputs are analog. I have one where I just put together a simple 2 bit ladder DAC tied across all three channels... As you mention it's ochre instead of brown, but if that matters I wouldn't think some simple gate logic to detect 0x06 to change out the resistance on green should be that big a deal.
 
How about just the mobo and as suggested a picoPSU? "Here's my bag of bits from 80s and it does this..." :D

LOL, that would definitely fit, but I don't know if I could forgive myself if the board flexed and snapped during transport.

Where is this? If you're going to be within a reasonable drive I'll deliver a 5155 to you when you get here. I'm sure others would do so also.

Cambridge, at MIT. That's a very sweet offer, but I couldn't ask that of anyone.

As far as CGA output to a projector goes, you could use one of the CGA video DAC boards that I am making, along with a GBS-8220 arcade scaler. That combo works _very_ well for CGA output to modern monitors.

I'd love to know more about this -- not just for this question, but for a future project that will do very strange things with CGA that I would like to try to capture with a conventional capture board (as opposed to shooting the screen with a video camera). Do you have more info about this on the web somewhere?

Its been a while since I've had hands on a 5155, but I actually remember it being SMALLER than a Compaq Portable I

I looked at the United luggage sizer today and got confused -- it looks like a 5155 will fit. I need to measure my own to see if it will and re-compare.
 
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