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Author Topic: cybervison 64/3D scandoubler in A3K  (Read 2745 times)

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Offline WhakaTopic starter

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cybervison 64/3D scandoubler in A3K
« on: February 08, 2017, 09:40:31 PM »
hello,
i need help for trying to do this mod.

i own a cybervision 64/3D with the scandoubler.
i want to run the SD in the 3000 because of the advantage of autoswitching.
and once you have the graphic card... loosing the flickerfixer is not a big deal.

so, i investigate a bit, and once you made the notch to fit it in the video slot, the last thing missing to get it working is a 28 Mhz signal, wich is missing on pin 5 of CN 451.

what i tried :
 
- pick the 28 Mhz directly on the 28 Mhz oscillator, directly on it's outpout.
it work, but not quite well, there's some phasing issue. so, the picture is not clean and sharp as it should be.

- pick the VDE28M signal, wich is generate for the internal SD/FF.
seems a better approach (it's adjustable thru VC470), but... and it's here i need help, the CV64/3D SD mess with the internal SD/FF when using this signal. and this can make the machine unbootable.

i need help to make them share this signal, without messing...
i try to remove amber, but it's not the solution.
i try to add an 1N4148 on the path, but it simply kill the signal (and by the way, i don't know if a diode could really be a solution.)

so, ideas are welcome :D
thanks !
« Last Edit: February 08, 2017, 09:45:35 PM by Whaka »
 

Offline WhakaTopic starter

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Re: cybervison 64/3D scandoubler in A3K
« Reply #1 on: February 12, 2017, 12:02:56 AM »
and... it's done !
i pick the VDE28M clock signal on the mobo.
i just added a 100 ohm resistor between the start point and the wire, and all troubles are gone.
if some people are interested in this mod, i can post some pics :)
 

Offline WhakaTopic starter

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Re: cybervison 64/3D scandoubler in A3K
« Reply #2 on: February 12, 2017, 04:54:42 AM »
Quote from: Oldsmobile_Mike;821987
I've never owned a CV64/3D but out of curiosity, was this mod required because your video slot is damaged, and not providing the proper signal, or is it required on all A3000's?
yes, it's required for all 3000 (and 2000 too by the way) because the SD was originally only designed for the 4000.

in fact, there's 2 mod to do :
- one on the SD itself because it doesn't fit in the 2/3000 video slot. by doing a notch on the pcb (and it's still useable in the 4000 :))
- and a mod to provide the missing clock the 2/3000 don't provide.
 

Offline WhakaTopic starter

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Re: cybervison 64/3D scandoubler in A3K
« Reply #3 on: February 13, 2017, 07:30:03 PM »
if i can, i'll test it in a 4000.
but i don't really understand the phase 5 choice too... as the CV64/3D is zorro 2 compatible. they really could have make it compatible with 2/3000 too.

for the moment, my experience is very good. this SD can provide a very clean and sharp picture with good color level. as good as the internal A3000 SD/FF.