SuperMac Spectrum/24 Project

[Phipli]

Yes, I think I definitely do have the original card. ROM 1.0 1989, just as Trash has. If that is the case, I would need to find one of these oscillators for the higher resolutions as per the tables attached, correct? Mine currently Outputs 640x480 to my Apple Color Display.

Can you share a photo of the card?

If it only has one clock oscillator, then you should swap in a 64MHz clock like this one :

MXO45-2C-64M0000 CTS Clock Oscillator 64.0000 MHz 50pF 100ppm 5V 14-DIP 4P TH | eBay

Up for sale are CTS Components oscillators P/N: MXO45-2C-64M0000. This Buy It Now is for 1 oscillator. Clock Oscillator XO. 64.0000 MHz. Local pickup is also available. 14-DIP, 4 Leads. 20.80mm x 13.20mm.

www.ebay.co.uk

I've not seen an original Spectrum/24 - mine all have three clocks and a spare socket.

 

[MacOSMonkey]

That oscillator is 64.000Mhz vs. 64.0000Mhz. The auction incorrectly states the frequency precision. But, any 64.000Mhz oscillator that is +/-100ppm should work fine. SuperMac originally used oscillators that were 64.0Mhz, but eventually improved the precision spec over time to 3 places.

 

[LaPorta]

Sure, when I am home this evening I will pull it and we will have a look at it.

 

[Trash80toHP_Mini]

Interesting, my crystal is the original spec: 64.0MHz

Forgot about the lack of pics, so now that mine has been freed:
______ Copystand lighting





Flash on copystand:

 

[Trash80toHP_Mini]

Yes, I think I definitely do have the original card. ROM 1.0 1989, just as Trash has. If that is the case, I would need to find one of these oscillators for the higher resolutions as per the tables attached, correct? Mine currently Outputs 640x480 to my Apple Color Display.

Now you've got pics for comparison tonight as well as my screencap of everything SuperVideo but the custom setup window. Presumably you'll find someone swapped out the standard 64.0MHz crystal for 30.24MHz to support your monitor. While you're at it, order up the 24.00MHz Crystal to play with multisync displays to go with the OEM clock. That should prove interesting.

 

[Phipli]

Now you've got pics for comparison tonight as well as my screencap of everything SuperVideo but the custom setup window. Presumably you'll find someone swapped out the standard 64.0MHz crystal for 30.24MHz to support your monitor. While you're at it, order up the 24.00MHz Crystal to play with multisync displays to go with the OEM clock. That should prove interesting.

I think the boards came with multiple clocks in the box and you put the one you wanted in the card. Your previous owner probably had a 16 or 19" Supermac monitor. LaPorta's probably had a 640*480 monitor.

 

[LaPorta]

The interesting thing is my SuperVideo control panel allows me to select from 640x480 through 1024x768 (though I have never tested any of these since I just became aware of the control panel, and my attached Apple Color Monitor only does 640x480). They are not grayed out. Perhaps this means I have multiple oscillators? No idea, but tonight I will see. I do recall my card looking at least a bit different than Trash's.

 

[Trash80toHP_Mini]

@Phipli ISTR reading it shipped with two crystals, the 64.0MHz can on my card and presumably the 32.24MHz can on LaPorta's because. The 24.00MHz oscillator was not included. Makes sense as the RGB was Apple's high end color display in that time frame. There was a ready market in the DTP workstation commonly set up with that monitor for spot color work in combination with a GS TPD or FPD for Page Layout.

If I get a chance I'll try to get the User Manual up so we'll all be on the same page. I can scan multiple pages to my email as a PDF.

 

[Trash80toHP_Mini]

Perhaps this means I have multiple oscillators?

Might mean you have the 24.00MHz can after all? Doubtful as the 640x480 resolutions are not grayed out in the menu running under the 64.0MHz clock?

Please post pics of your card for comparison!

 

[LaPorta]

When I get home this evening, I'll pop it and and we will have a look!

 

[LaPorta]

Someone just put a SuperMac up for sale a minute ago:

https://68kmla.org/bb/index.php?threads/fs-nubus-video-apple-8•24-670-and-supermac-8•24-spectrum-pdq.42042/

 

[Trash80toHP_Mini]

PDQ with sockets for four different crystals looks interesting, if not useful in this endeavor.

 

[Trash80toHP_Mini]

Looks like I need to do it over using the bottom edge for registration as the page numbers are missing and there's plenty of room for cutoff at the top. Drat! If someone can repost this in the proper orientation that would be great for now. No biggie, but a PITA to have to rotate it every time. Can someone OCR the thing or should that wait until I post a clean, page enumerated version?

 

[Trash80toHP_Mini]

 

[LaPorta]

Ok, well, my card certainly does look a whole lot different as yours as far as layout. It also looks to have the oscillator built-in, and a slot for an additional oscillator...and maybe solder points for two more slots??

 

[LaPorta]

Thanks for the manual! Reposted:

 

[Trash80toHP_Mini]

I've got it scanned into two files with chapter/page enumeration intact:
Cover to p.59
p.55 to End

Can someone piece them together and post it with OCR'd TXT?

Meanwhile:


I'm officially in over my head once again, but it looks like a fun ride coming up!

 

[MacOSMonkey]

LaPorta, your card is not a Spectrum/24. It is a ColorCard/24 (aka Calvin) without the daughter accelerator card (aka Hobbes) that goes on those 2 connectors. Also, it does not have enough video RAM to do 24-bit at 1024x768.

In addition, when you see the choice for 1024x768, it is because, at a base monitor resolution of 640x480, 1024x768 is a virtual desktop configuration. However, it should work in 8-bit mode at 1024x768. I think that might also work as a custom configuration on that card if you slot a 64Mhz oscillator.

 

[LaPorta]

Thanks for that! Not sure how I didnt notice that before...

Can you stick more than one oscillator in there at a time?

 

[MacOSMonkey]

You would have to experiment. You could try adding a socket to the 3rd position to see if it detected anything. It might or might not. Don't recall.