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Posted: 19 Sep 2017, 14:10 

I decided to grab one of the video capture cards with the same chip as recommended by the documentation. I wanted to test with a 'known' set up before replacing it with the 10-bit ADC (that is currently waiting on parts).

I realized that I needed a VGA amp or something to boost the signal; but Ebay prices were not so great :) So I designed a simple one (based on a common design) that does the trick for a couple of Euros/bucks. It runs from 5Vs, so it's easy to power from USB, a power supply, or whatever. I ran some bode analysis on it and fed the ADC from a function generator and checked the resulting sample... all looks good. Seems the video capture card input could do with an anti-alias filter, but that's another issue.

Schematic is attached; it's so simple you could build it on a stripboard in half an hour :)

My PAL decode questions will begin soon, but I wanted to give something back first!

ld-decode video amp.PNG

P.S. The 47R resistor on the output sets the output impedance and can be changed if you need more or less.

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Posted: 14 Nov 2017, 10:25 

Just a quick update; the production boards are now designed and I'm in the process of ordering some to continue testing with. Here's a render of the board design:

Domesday Duplicator_Render.jpg

Software is still on-going; but I'm getting there :)

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Posted: 21 Nov 2017, 19:39 

Quick update... Software is on-going (still quite a bit of work to do), but the first production board is now ready for testing (hopefully it will work!). If all the tests work out, then I'll make a couple more.


Still working on the capture application and also adapting the software to the new board (which has a completely different FPGA footprint from the prototype). However, progress is progress :)

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Posted: 25 Nov 2017, 17:02 

Hmm. Seems as though this hardware could be adapted for use as a MUSE decoder (which is much more simple computationally anyway).

I'm still hacking away at the software right now, but the project is completely open-source and open-hardware, so you will be welcome to use it for any purpose (although I would advise patience until it's in 'release' state). I will also put the final Gerber files up on the GitHub so you can easily get PCBs made too. The development environment is Ubuntu 16.04 LTS, so it should be fairly easy to get the development tool-chain running - I'm also planning on writing both a software and hardware (assembly) guide complete with a detailed component BoM.

I won't be making any 'mass' production runs of the board (my target is purely the Domesday86 project which requires a maximum of 3 boards), but I will do everything possible to make it easy for anyone that does want to make some (for personal use or for sale to others).

In other news, I have 3x Pioneer LD-V4300D machines being delivered shortly so (back on the ld-decode side) I will be able to start testing both NTSC and PAL captures.

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Posted: 12 Dec 2017, 07:16 

I realize I've been quiet about the duplicator board progress, so here is a quick update:

I've completely rewritten the FPGA code for the project to make everything more robust and to increase the level of system testing and the error checking. The design now runs the FX3 (USB 3) communication at 64 MHz (double the capture speed) to allow better buffering and 'catch-up' when the PC slows down for any reason - the non-realtime nature of a PC performing the capture to disk causes bursting of data via the USB3; this is now much better implemented.

I've also written a Linux (Ubuntu) GUI front-end application in QT which monitors and controls the capture process. The latest github build is a fairly simple GUI, but contains a robust USB and disk buffering implementation that has been tested successfully with capture runs of over 60 minutes (generating in excess of 250Gbytes of capture). By making an open-source Linux application specifically for the duplicator I can now expand the functionality at will to make the capture process far more user-friendly. Also the whole 'chain' of the capture and decode process can run on a single Linux machine (before the capture relied on the Cypress FX3 Windows test applications for capture).

I have now received 3 Pioneer LD-V4300D laserdisc players and these players will be the reference hardware for testing the Domesday Duplicator board. The new players are both NTSC and PAL capable, so they represent a much more universal approach than the Sony PAL player I was using previously. To get the best results the players need to be correctly calibrated and set-up. I've ordered the required Pioneer 8" test disc (from PacParts in the USA) and some service remotes - I also have the service guides and the test equipment required.

I've also just ordered the parts to make up a couple more Domesday Duplicator boards; these should be ready by the new year and will be used to expand the testing scope (one will go to Mr Happycube and the other will be a secondary test card for my own rig).

I'm also planning on implementing what I call "Player Integrated Capture" into the Linux application - this will provide automatic control of the LD-V4300D from the Linux GUI. Full and partial disc capture will be controlled automatically between the Linux app and the player using the RS-232-C player interface. This should take out the hassle of capturing disks and allow additional things like multiple captures of a range of frames where the GUI pauses on a frame automatically, checks the player is where it should be, captures, and then moves on. Once the VBI frame position information is exposed via ld-decode, this should allow for really smart capture techniques - especially when only one source laserdisc is available. Basically you will be able to specify a frame or range of frames in the app and it will all happen automatically. My plan is to implement this in 'layers' so others can easily add in support for additional laserdisc players.

Once the new LD-V4300D machines are running and I have an end-to-end tested capture, I'll push a Github release (hopefully in the next 2 weeks). After that, everything is just 'enhancement' work :)

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Posted: 13 Dec 2017, 21:20 

Well, the good news is that the capture system is up and running again - the Linux GUI app needs more work (cosmetic fixes and non-capture related bugs); but I now have a modified Pioneer LP-V4300D with the RF tapped. I haven't calibrated the player yet (I'm waiting on a service remote control and Pioneer 8" test disc to be delivered). The whole software base is now far more robust and reliable with better design everywhere, especially around the FPGA dual-clock domain FIFO buffering; the USB communication is now 64Mhz (double the capture rate).

ld-decode seems to be happy with the captures however there are some issues with both black and white colours being very speckled and not very black (or white); but I'm sure this is just some ld-decode calibration issues.

Happycube - expect some rather large captures from the Jason disc and the Domesday Community South disc (I'm grabbing a frame dump of all of the test cards). I'll also include some NTSC from the Fantasia disc since I can now capture both formats. I don't have any NTSC testcards (yet), so some animated frames will have to do.

For everyone else; here's a pretty lady from the Jason disc captured using the new set up :)


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Posted: 14 Dec 2017, 21:15 

The Domesday Duplicator is now in release status. I'll be working on enhancing the Linux GUI front-end some more, but the whole set-up is now working end-to-end from the high-speed DAQ through to the Ubuntu GUI.

Documentation is fairly complete and includes construction information, bill of materials and much more (but requires more detail especially around the GUI). You can find the documents via the following links:

Hardware guide:
Software guide:

The Github repository is available here:

This release is primarily for testing with ld-decode (rather than prime-time use) - but if you are interested in how it works and what it is, all of the required information is now available.

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Posted: 17 Dec 2017, 08:35 

As I mentioned before, the Pioneer LD-V4300D is the reference player for the Domesday Duplicator board. I currently have 3 of these players and I'm busy restoring and repairing them to get them in the best condition possible. Along the way I'm trying to produce comprehensive documentation about the player and how to modify and restore it. I will make an electrical calibration guide shortly (I am still waiting for the Pioneer test disc). In the meantime, the following guides are available:

Overview of the Pioneer LD-V4300D (includes serial cable pin-out):
Pioneer LD-V4300D Tear-down and clean:
Pioneer LD-V4300D – Adding an RF output:

Even if you have no intention of using the duplicator, the tear-down and clean guide is a good way to extend the service life of the player.

The overview guide also includes a PDF of the user manual (which I was unable to find online, so I made a copy myself) - it includes a guide to the serial control commands, so it's quite useful.

If anyone spots any errors or the like, please let me know!

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Posted: 26 Dec 2017, 10:38 

Glad you liked the guides :) I'm trying to make sure this work is as 'universally useful' as possible!

The Domesday Duplicator software is using the LD-V43000D as the reference player and provides fully automated CLV and CAV capture; so it's getting easier and easier to quickly and accurately capture RF. My aim is to make it as 'untechnical' as possible for end-users. Here's a view of the latest github of the capture software:


Nearly there! :)

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Posted: 26 Dec 2017, 11:10 

Short answer: It's digital, plug in the DA-1

Long answer:
The player band-passes the modulated RF signal to separate the digital audio part of the RF signal from the rest of the RF and then outputs it to the EFM port (the AUDB module in the player handles this - service manual page 25 of the PDF).

The AUDB module also decodes the digital signal and outputs the status of the L and R digital audio channels on the EFM connector too (pins 3 and 4).

So you have:

Pin 1: High if the disc is PAL and low if NTSC
Pin 2: GND
Pin 3: Audio L status (high if on and low if off)
Pin 4: EFM (this is the actual 'digital' signal)
Pin 5: Audio R status

Interestingly the EFM isn't really a digital signal; it's band-passed RF. This still requires some form of demodulation to get the data back followed by a DAC to get back the analogue sound; which is most probably what your DA-1 is for. In the player IC306 demodulates the RF (the "EFM decoder IC") and then IC308 acts as the DAC).

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Posted: 30 Dec 2017, 17:20 

Thanks for the kind words :) Happycube is working hard to get the ld-decode working with the new hardware (there are now two boards, one in Sweden with me and one in the USA with Happycube) - the software for the duplicator is gradually becoming stable and more user-friendly too.

Just for fun I ran some frames from the PAL Jason and the Argonauts disc through the process end-to-end (Pioneer LD-V4300D RF -> Duplicator -> ld-decode -> photoshop cropping and filtering -> Premier Pro video editing and encoding) and popped the results on YouTube as an unlisted video). Bearing in mind that things are far from perfect in the decoding (at the moment), the results are still extremely impressive...

Once we are a little closer to the calibration required for the BBC Domesday Project discs (they are a lot older and degraded than a modern disc like Jason) then I will start to run more test captures.

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 Post subject: Re: [LD-V4300D] Calibration
Posted: 13 Apr 2018, 21:26 

which app for android is this exactly?
The application was called IRPlus.

I've now received and tested the CU-V113A remote and it does indeed cause the correct keycodes to be detected by the player. So, the existing IR code configurations available on the web are incorrect for the multi-rev and multi-fwd keys. They are also incorrectly mapped in the RMC12010 3rd party replacement service remote. Presumably the keycodes were changed in later revisions of the service remote after the GGF1067 and no one thought to double-check.

I've scanned the IR output from the CU-V113A using ir-keytable in Ubuntu and added the correct hex-codes for all of the keys to the LD-V4300D overview page on my website (along with a hires scan of the remote):

Thanks for the help scytales!

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Posted: 21 Apr 2018, 20:20 

I've just pushed a pre-release of the new Domesday Duplicator software to github:

This version has many improvements and bug-fixes and includes new GUI application code, Cypress FX3 code and FPGA code (you will need to update all three). The release is compatible with the 2_0 revision PCB (you must set DC compensation to on though in the GUI) and the github has the new revision 2_2 PCB and Kicad schematics. The revision 2_2 board is awaiting test though (I'm waiting for PCBs to be delivered from China before this can begin).

The new software supports 8xFSC sampling for NTSC (at 28.8 MSPS) and PAL (at 35.5 MSPS) rather than the fixed 32MSPS sampling of the previous version. There's also a lot of improvement around error handling to make the GUI usable without needing the debug output when things go wrong with device communication.

I've also revamped the build environment (and ironed out some multi-threading issues) so the GUI can now be built in release mode from the Ubuntu command line (makes it simple to build and gives it an Ubuntu look-and-feel):


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Posted: 21 Apr 2018, 20:25 

Here's a sneak-peak of the 2_2 PCB. It's smaller (to get the length under 10cm which reduces the cost for fabrication since 10cm is usually the 'price-break' point) and has been much more carefully laid out to make it easier to construct. The silkscreen is also greatly improved to make it both better looking as well as clearer as to where the components go. It also has a fix for the DC offset issue, but that is subject to test (however the board can be configured to act just like the 2_0 version if needed). All the documentation has also been updated on

Domesday Duplicator V2_2 small.jpg

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Posted: 01 May 2018, 05:59 

I know this topic is primarily about making a copy of the (analog) video

That's not entirely the case :) The digital information on the disc is also encoded in the analogue modulated signal using a technique called EFM. If you capture the raw RF you get everything on the disc without exception.

This is the reason why I designed the Domesday Duplicator for my project to preserve the BBC Domesday system:

Although Domesday is PAL; the duplicator works with both NTSC and PAL. However... capturing the raw RF preserves the information on the disc, but it doesn't allow you to simply read it; for that you need a decoder (which is what ld-decode is about) - right now there is no capability to decode the EFM data, but it could be added. The details of how this is done is contained in the following (commercial) IEC specifications:

IEC 60856-1986 Laservision PAL
IEC 60856-1986 Laservision PAL Amendment 1
IEC 60856-1986 Laservision PAL Amendment 2
IEC 60857-1986 Laservision NTSC
IEC 60857-1986 Laservision NTSC Amendment 1
IEC 60857-1986 Laservision NTSC Amendment 2
IEC 60908-1999 CD digital audio system

The last spec about CDs is because the EFM encoding was developed for CDs, but used for LaserDiscs to provide both digital data and digital audio.

I've written a high-level description of the way information is decoded by a LaserDisc player which you may find useful:


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Posted: 14 May 2018, 12:01 

Nice work on the Windows port! Looks promising :)

Since there is a lot of discussion and interest around the Domesday Duplicator (as well as the Domesday86 project as a whole) - I've just made a facebook group for the project where people are welcome to ask questions and seek support. Anyone interested is welcome to join:

Somehow I need to control all the emails and PMs I've been getting recently :)

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Posted: 20 May 2018, 15:10 

Nemesis> To try an make your life a little easier I've made a short (10MB) capture of the colour bar frames from the NTSC GGV1069 reference LaserDisc and uploaded it to the Domesday86 website. It's only a few frames, but it should be more than enough for you to run your testing against.

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Posted: 27 Sep 2018, 13:26 

Just a thought, but if you connected that 'fob' to a serial to USB adapter (a TTL level one like the arduino's use) and connected it to a PC, then connected the +5V, it would fire up and you could read out the commands it's using to do the region free trick... then you could publish the codes required here (or make more dongles and sell them as gold bars :) ).

Either way you would then know the serial speed/settings and at least a few of the available commands.
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