phantom bus accelerator & clock patch

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Steve
Posts: 2609
Joined: Fri Sep 15, 2017 11:49 am

Re: phantom bus accelerator & clock patch

Post by Steve »

Just some photos of the clock patch I made myself from the Phantom schematic, I *know* it isn't the prettiest but I was proud of myself :)

Schematic:
phan.png
phan.png (51.45 KiB) Viewed 2885 times
Backside of my pcb:
IMG_20180510_182317.jpg
IMG_20180510_182317.jpg (380.45 KiB) Viewed 2885 times
Front side of pcb:
IMG_20180511_134149.jpg
IMG_20180511_134149.jpg (405.82 KiB) Viewed 2885 times
Connection to DSP line:
IMG_20180511_134410.jpg
IMG_20180511_134410.jpg (370.94 KiB) Viewed 2885 times
Connection to SDMA line with capacitor to ground:
IMG_20180511_134446.jpg
IMG_20180511_134446.jpg (318.1 KiB) Viewed 2885 times
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exxos
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Re: phantom bus accelerator & clock patch

Post by exxos »

Cool.

I actually found the capacitor made things worse.

Looks like the second chip does a inversion.. 40ns delay at 25mhz.. but with the delays of the chip, its probably more like a buffer..
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Steve
Posts: 2609
Joined: Fri Sep 15, 2017 11:49 am

Re: phantom bus accelerator & clock patch

Post by Steve »

Also ctirad recommended for me to add these extra capacitors to my clock patch, but for some reason the Falcon wouldn't boot afterwards. Still, I took a photo for my records. I had to remove the capacitors afterwards. I think I remember him saying it was strange, apparently it should have just smoothed out the voltage a bit more.
IMG_20180512_183759.jpg
IMG_20180512_183759.jpg (166.29 KiB) Viewed 1671 times
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