Unofficially Official LD-Decode thread

[lipscgr]

It is actually very minimal modding. There is a ribbon strip connector attached to the circuit board. I am assuming most players are slightly different. Basically you just need a coax type connector and connect the cable shield to the ground and the center copper strip to the RF pin. You just have to locate the RF pin and the GRND pin. You just unplug the original connector as it is not needed, and plug in the modded connector. You could drill a hole in the back and mount the new connector, or if you did not want to do that, you could leave it open.
I think the point of this would be to buy a cheap player for the sole purpose of doing this mod. I would not mod any expensive player. I believe all cheap units should be able to produce a clean/accurate RF signal, as this is nothing more than modulating the direct output of the laser.

[Danfun64]

The answers I got from Happycube:

1. I hacked up a video capture card to work as a direct ADC, then capture the raw RF signal from a test point on the Laserdisc player. This bypasses the signal processing/video output electronics, while the player itself works normally.

The raw signal is then demodulated into (analog) audio and video, then framing and comb filtering/color decoding are done in software. http://imgur.com/a/7VNff shows each stage of the process.

2-3. I think the X0 would win in either case, at least until the analog->digital conversion is upgraded. This is the best direct comparison I could come up with between the X0 and ld-decode (using a CLD-V2800, a rather low end player!): http://screenshotcomparison.com/comparison/128845

If my tinkering with an RF amp circuit is successful, the gap might close a little bit. Eventually I may cook up a circuit using the LPCLink2 (with the same LPC4370 chip found in the AirSpy), which I suspect will give better results.

4. Not much at all, I need good quality VHS RF samples (and/or the time to hack up a VHS deck, I've got a couple of Panasonics to butcher sooner or later). Also note that dealing with Macrovision will not be a priority.

[spoRv]

As I always wrote, LDdecode gives very nice results, even more interesting if you consider the hacked laserdisc player used for the comparison is not an high end model... I'm almost sure that PAL LDdecode output will outperform any PAL laserdisc player!

[lipscgr]

You can tell that the X0 is a little better, but it is really a close comparison. It might be something I could do. I have no intentions of buying an X0 though.

He did not explain very well in his post how he went about hacking his video capture card.

[Laserman]

I have an X9, would it be suitable to modify? What card is required to capture the RF signal, I would imagine interference would be a potential problem.
Is there a step by step guide?

[spoRv]

Take a look here, it could help:
http://originaltrilogy.com/forum/topic.c...Post776120

[happycube]

He did not explain very well in his post how he went about hacking his video capture card.

That's because (a) I'm not great at documenting things, and (b) the hack is entirely a special Linux driver, no hardware mods needed Years ago someone figured out how to turn a particular Connexant chip (CX23880) into an ADC, and I took that driver and updated it to work on current Linux kernels, and improved the quality over time as well.
https://docs.google.com/document/d/1n5VA...7Vu7OYoRg/ - linked to from elsewhere - there's useful stuff there, albeit disorganized.