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Posted: 06 Apr 2017, 18:02 

happycube wrote:
Cool :) How well does it play? (31-32dB isn't that great for a handpicked disk, but I guess it was acceptable to them then)

I purchased this from cjm and can report that it looks much, much better than what you'd expect from 31-32dB VSNR.

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Posted: 13 Sep 2017, 09:19 

Hi everyone,

I understand that the forum has been slowing down because, well, we already talked and discussed 99% of what could be said/explained on LD and LD Players over the years.

I can see that visitors are reading/searching the forum but less contributions these days, except maybe in the "technical questions" for Players starting to age and slowly breaking down.

There are, however, a LOT of good posts and great information laying deep in the old topics that would benefit from more exposure/indexing.
After considering several options, I decided to give "Thanks for Posts" a try: https://www.phpbb.com/customise/db/mod/thanks_for_posts
thanks.png
For now you can add a "thank you note" on a post linked to an active account (not yours obviously, this is not Facebook!) and when enough thanks are received, I'll be able to pull out a list of popular topics and posters (in quality, not in quantity or most recent posts).

If you bookmarked or liked an old post, don't hesitate to go like it to give him a chance to shine again for newcomers!

And if you want to enable notifications (PM or Email) when someone thanked you, you will have to update your User Profile here:

http://forum.lddb.com/ucp.php?i=prefs&mode=personal

UCP.png

Julien

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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:

Attachment:
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.

Completed_Board_2_0_small.jpg

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: 10 Dec 2017, 18:23 

So the project is basically dead because I got it working without a scope, here is what I did -


Started with centering adjustment as Kurtis has described (half way between points where a CD will stop playing) and got CD playing with chapters.

Next moved to tracking balance and trial and error until it would read an LD with chapters (this was huge breakthrough, couldn't get it to do this before).

Digital audio was distorted so fine tuned RF level up until digital was clean.

At this point it would not get to the end of a side without huge crosstalk so I adjusted tilt balance (with disc playing) until everything seemed to play clean.

Now it appears to be playing clean side a and side b, verified AC3 is working as well as digital audio.

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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 :)

frame-7.jpg

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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:

Overview: http://www.domesday86.com/?page_id=978
Hardware guide: http://www.domesday86.com/?page_id=1066
Software guide: http://www.domesday86.com/?page_id=1070

The Github repository is available here: https://github.com/simoninns/DomesdayDuplicator

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): http://www.domesday86.com/?page_id=1176
Pioneer LD-V4300D Tear-down and clean: http://www.domesday86.com/?page_id=1142
Pioneer LD-V4300D – Adding an RF output: http://www.domesday86.com/?page_id=1265

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: 09 Jan 2018, 10:19 

We all know that the infamous VNL1779 isn't manufactured anymore by Pioneer and for several years it has been both expensive and difficult to find. Since I'm studying 3D technology at college right now, I've decided to recreate the M holder with the help of IronCAD and several 3D printers. I'll do several prototypes and once I've managed to get it right I'll then be able to make some of these (hopefully with a Fortus) for those of you who need one. I'll also publish the final stl files on Thingiverse so anyone'll be able to download them and play for themselves.

Since this is a project for educational purposes, I cannot charge you for any of this (apart from the shipping). You may not use the finished parts to make any kind of profit neither. You may only get one for individual use.

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Posted: 11 Jan 2018, 06:25 

Ok so I painted on the plasti-dip, I made a few different attempts to get it how I liked, which was trying to get an even coat but also with some texture to it, ended up with putting a single coat smooth, then going back and lightly "sponging" with the brush while it was tacky.

After a few hours of drying it actually leveled out quite a bit, maybe not perfect but the wasn't what I was going for. not sure how it would compare to spray but brushed on it seemed to come out fine.

Fired up the player and....it works! So far just brief testing, but I did a few side changes and stops and it did really well, Once though it did slip on a spin up an fail to play, but that particular disc was giving me trouble before and I think the label is dirty.

Otherwise very smooth, quick side change and stops dead right away, the question is if it will hold up in the long term. I'm impressed so far, wasn't so sure of a first attempt but...so far so good...

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Posted: 19 Jan 2018, 18:56 

I can report after playing discs the past week there have been no issues, I've watched a handful of films including a CAV 3 disc set, all played perfectly, also tried to note the labels before and after playing, some already had marks on them (probably from another bad ring) discs with with clean labels seemed to be undamaged after playing, no marking from what I could tell.

I did get a sheet of slip tape, but like Kurtis described it is hard vinyl like and has a grit surface, probably not another solution for this.

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Posted: 03 Mar 2018, 17:34 

I haven't said anything here in the last month, but I've been busy. I found the new TBC app like the old one failed pretty badly at a lot of real-world signals I tried to throw at it. Originally I started working on improving the code, but I found it seemed to be entirely based around expected values from the NTSC signal specs, and was quite rigid and hard to adapt from that point to be more tolerant of other signals that didn't conform to its expectations. I ended up heading in a different direction and writing something new from scratch. It's still early days, and there isn't any repair process in place yet for really badly damaged sync events, but I've got a workable program now that can take raw composite video signals (such as the one output by lddecode.py) and identify sync events, group into frames, and synchronise lines. There's no colour decoding yet, but here's the kind of raw frame output I get right now on the Fantasia sample I used before:
http://preview.ibb.co/eVVrYS/image.png

And here's a frame of progressive video from Sonic 2, which I couldn't decode previously:
http://preview.ibb.co/jXWgYS/image.png

The next big thing is adding colour decoding, which I'm not really looking forward to, but I'll give it a shot sometime soon. I've put the code up on github at https://github.com/RogerSanders/avtoolkit .

Some of the main advantages this has over the previous decoder are as follows:
-Universal format support (Can decode signals with any number of lines, any line/sync timing, progressive or interlaced)
-Supports any sample type (templated code allows any data type to be used)
-Supports any sample rate (adaptive processing algorithms scale to the length of detected events in the data stream)
-Extensive source comments and cleaner code structure
-Better performance (Efficient algorithms and multithreaded processing gives over 5x speedup on my PC)
-Cross-platform code with no external dependencies (Only Visual Studio projects provided right now for Windows compilation. I'll add a makefile soon for Linux compilation.)

It's far from perfect yet, but the elements are there to build from. If my interest keeps up, I'll split the core processing work out to a library, so a set of thin tools can grow around the common set of code. I'd like to get this to the point where it can decode basically any analog video signal.

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Posted: 04 Mar 2018, 15:53 

Haven't looked at your code yet, but it sounds good :)

To do color decoding easily, you need to get the signal going into the comb filter into a phase-aligned signal clocked at four times the color frequency. Once you have that the math becomes a lot simpler since each pixel is at a different 90 degree phase and you can do some relatively direct computations to get the YIQ signal albeit with considerable cross color, but once you have that making it a 2D comb filter is easier.
Thanks for the tip. Right now I load the line samples into a cubic spline so I can sample arbitrarily at any point along it, and it'll interpolate from the original sample values. I'm aiming to perform the colour decoding directly from this spline representation rather than a resampled form, as then any (further) loss converting from the sample data is minimized. I already decode the colour burst and phase lock to it, as like you I use the phase of the colour burst signal to help synchronize line start positions, so it should be simple enough to start performing colour decoding with the information at hand for each line. It's really just digesting the formulas I'm seeing on the page and figuring out exactly how to turn that into code that I need to dive in and try. I'll start with very basic decoding, without any smarts to try and eliminate crosstalk, and work up from there. Once I've at least attempted that myself, I should hopefully understand enough about the process to be able to interpret what you've already done, and figure out ways to build from there.

You could also recreate the format of the original output and pipe it into the comb filter in ld-decode. (Maybe I could - I just haven't had that much oomph outside of work lately)
I have no doubt this could be done. I hacked your program to dump out raw frames during decoding to compare with my own, so I know what I'm producing is close to the output you were getting. It took me a damn long time to match the results of your line synchronization by the way, you did a great job.

Check out Video Demystified (there are some .pdf's of earlier editions floating around out there) - it goes into digital processing of composite signals.
Yep, found that little gem just last week. A colleague at work heard what I was working on and unearthed it from a shelf. They got it for an aborted 25 year old project and it's been gathering dust in the corner ever since. I tracked down PDF's of later versions afterwards, but I'm glad I got my hands on the first edition. The later versions have a lot less information on analog video, as they focused increasingly on digital standards.

I've been busy working on something else too. This weekend I assembled this:
http://preview.ibb.co/iYJ5A7/image.png
I'm still waiting on the inductor coil from another supplier, but I'm hoping that'll come in the mail tomorrow. After that, it should be good to go!

I'm also sitting on a stack of these:
http://preview.ibb.co/kycJxn/image.png
It only cost $5 more to stamp out 20 of these boards, so that's what I did. If anyone wants a bare board, drop me a line.

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Posted: 16 Mar 2018, 22:25 

If you watch all old movies on LD and only new ones on BR you’re missing out on a LOT. The fact that you even make that distinction on purpose makes me feel you put too much thought into this kind of thing. If you aren’t enjoying LD then please sell your stuff to someone local and move on.

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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:

https://github.com/simoninns/DomesdayDuplicator

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):

DdD_GUI_application.jpg

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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 https://www.domesday86.com

Domesday Duplicator V2_2 small.jpg

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Posted: 17 May 2018, 14:29 

I'm only working on NTSC decoding right now, so the PAL test cards aren't much help yet. I don't have any test card samples for an NTSC signal. I tried to capture a generated one from a test ROM for the Mega Drive via the composite video stream today, but I had trouble getting my test machine to cooperate. A straight composite signal isn't in the right range for the Domesday Duplicator analog input, and cdaxc kept on dropping samples randomly for some reason. It's worked before, so I'll have another try later. I should be able to get something usable out of it.

About a million bug fixes later though, and I have something that's vaguely in the region of viewable:
http://nemesis.exodusemulator.com/MegaLD/FantasiaColourDecodeColourWIP1.png
What I'm discovering is that phase locking to the colour burst is hard! I underestimated just how sensitive it would be. The slightest variation and the hue goes off in perceivable ways, but from the RF the signal isn't even regular, and captures from consoles and other equipment I have which generates composite video shows they have their own problems and idiosyncrasies, from field timing that's off NTSC spec, to colour burst waves that look more like triangle or square waves, with length and position wildly varying. Analog receivers cope with them all though, so you can't just go by what the specs say, the software needs to at least be able to cope with anything an analog set could have thrown at it, because there's a kaleidoscope of "incorrect" signals out there that work anyway. I'm trying to write software which can adapt to all this, but writing something that's adaptive and tolerant of signals that are generated off-spec, while still pulling in imperfect signals which aren't regular back into conformity so the image is stable and correct, isn't an easy task. Underlying all this there's the loss of information problem, in that as soon as we quantized the analog waveform we approximated it, and even with good interpolation techniques, it's never quite as easy to derive precise, accurate information about the true frequency of a waveform, or the exact points at which it crosses certain thresholds, as it is to build an analog circuit which naturally derives that information in a precise, adaptive, and near perfect manner from the true analog waveform.

I can see I need to take a good look at the TBC issue again, and separate it clearly from framing. I need to first of all decide what the "correct" timing appears to be for the video stream, then use that information to perform TBC to force the input signal into conformity to that, but without distorting the hue mid-line by stretching or compressing the signal inappropriately. You've got a damn near perfect process working for that already happycube, but for a limited range of input signals. I'm going to have to spend some time planning an alternate approach here I think, which can achieve the same great result you've obtained, while making it more adaptive on the range of input signals it will accept. I might start by grafting in your existing comb filtering code into the back-end of my video decoder, so I can use a mature colour decoding process, and focus on making the input to it more flexible and adaptive. Once I've got that process getting a result on par with what you're currently achieving, but with a wider range of signal support, I can focus more on the colour decoding issue itself. Even without further work though, at that point I think it'll be up to task for a lot of things I'd like to use it for.

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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.

https://www.domesday86.com/?page_id=1332#NTSC_Test_card

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Posted: 29 May 2018, 12:42 

I just found another one player on sale it's Panasonic LX-V810 which I never heard you guys talk about it.
There's a video of the seller demoing it on youtube: https://www.youtube.com/watch?v=HTAAXkMMDWo
He asked a bit over $100 for the player.
I just called him and he suggest I have to pick it up at his room 30 min from my home,he suggest a pick up and test the stuff in person that's a good sign right there at least I don't have to worry about frustrated underpaid post officer throwing and slam stuff on the table or a shipping carrier that runs on scam.
Well it seems like you either get this player or you don't get any player.
For your location and monetary situation this is your best option and if you do plan to take the risk then this is it.

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 Post subject: Re: Muse Laser Pickups??
Posted: 21 Jul 2018, 22:40 

happycube wrote:
Looking at the service manual, the X9 pickup looks similar to the 99/70x pickup and the pinouts match. Has anyone seen if they work in the latter?

(if the remaining pickups were in the $100 range I'd experiment myself...)


They operate at different voltage levels, not interchangeable

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 Post subject: [GLOBAL] Replacement BELTS
Posted: 25 Jul 2018, 02:08 

Thanks to Kurtis, we can more easily look up for replacement BELTS (or good contenders) with:

http://manuals.lddb.com/LD_Players/PRB_Belt_XRef-extract.pdf (I extracted only the pages relevant to LD Players)

You can lookup for part number (ex: PEB1138 ) or close matches.

Standard ref provided can be matched the with Belts size list .

Good luck and don't hesitate to provide any matching combination/replacement belt size for others to use.

Julien

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Posted: 30 Jul 2018, 13:31 

It appears you might just have what the error indicates; the focus is off on the laser.

As laser pick-ups age and lose some of their light output, this could be the beginning of the end for it. However, you could also just open up the player and see if you could find trimpots with some labeling that say things like “t-gain” (tracking gain) or even “focus offset”. You should take pics of the pots current position before messing with them and only turn them very slightly to see if any noticeable improvements occur.

Another issue is possibly check the overall alignment of the mechanism itself. I once acquired a CLD-D704 that had tracking issues near the end of a disc on side A and constant skipping on side B. A technician I brought it to said it would need a new laser pick-up at a cost of $400. I said no way and just stored the unit in the meantime to possibly get a 2nd opinion at some point. A few months later, I acquired a CLD-D703 that worked perfectly so I decided to compare it to the 704 to see if I would notice anything odd. Almost right away, I did observe that the 704’s entire gamma turn assembly was a bit crooked. Thus, I basically grabbed it with my hand and slowly started to bend the entire assembly until it looked more like the 703. Low and behold, after a few days of tweaking and testing, the 704 was totally perfect and never skipped again on either side of a disc.

So lesson learned from me; don’t always trust a repair shop cause you never know if they’re dishonest on purpose to try and make a buck or they might simply be a moron. In addition, try to have another similar machine around cause seeing a working example can help one glean some hint on what is happening (I also fixed a friend’s 703 that was damaged in shipping by comparing my unit to his; he had a damaged plastic part that adjusted the tilt of the carriage assembly).

Hope some of this might help you out.

Thanks. After my post, the player spat out a H2 code and died. I took it to a local repairer who had been in business a while and has had experience with Laserdisc players. Two weeks later and the player is back in my rack working. The issue - dead and dying caps. Meaning the playing was being under powered. He replaced every cap for $130AUD ($96 US) - a great deal. Every issue is now gone!

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Posted: 01 Sep 2018, 04:35 

Hope to be proven wrong but a new production LD player is pretty much a pipe dream.

The engineer teams who designed and mass-produced these Players all retired a long time ago and their teams got terminated early 2000's anyway.

Analog video design is a lost art -- SONY couldn't fix a MUSE Decoder only years after selling them -- and almost everything is digital now.

We have to make sure we can salvage working parts from broken players to keep them running as long as possible.
My next coding time (from November when I move back to France without a daily job) will be to work on the Player database + parts. A long time overdue project!

As seen a couple times here recently, we're getting into the 20~30 years of lime time and it's definitely time for a refresh of capacitance with newer parts.

Julien
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