Jess Ragan Posted May 27, 2013 Share Posted May 27, 2013 I picked up a Casio TV-980 for two dollars this afternoon. That's a pretty sweet deal for a portable display, even if it is only passive matrix! I'd like to use my latest find in a hacking project, but I'm not sure how I'd connect it to a home game system or a TV Games unit. The television has a port on the top marked EXT ANT which can apparently be used with a specially designed RF cable, but I don't want to use an RF signal... it gives you a crummy picture, and most TV Games units just don't support it. After some research,I dug up a user manual which suggests that the PAL models have support for a miniature composite cable. You think there's any chance there are audio and video pins on the circuit board of this NTSC model that I could just solder wires onto to give the television composite support? Also, how can I force the system to display from composite, rather than default to the now-worthless antenna? This may be beyond my capabilities, but I'd like to get some use out of this television if it's at all possible. Any advice, as always, would be appreciated! Quote Link to comment Share on other sites More sharing options...
Osgeld Posted May 27, 2013 Share Posted May 27, 2013 yes you can, I did it to a sony watchman, though it takes some poking around, in a nutshell near the LCD screen you want to find the point where it converts the incoming signal to the RGB signal for the LCD, on my sony it was a composite NTSC to RGB converter chip, and since the RF circuits were on daughter boards I just removed them ... audio is just tracing from the speaker back to an amp chip http://hackaday.com/2011/10/03/hack-a-watchman/ Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 27, 2013 Author Share Posted May 27, 2013 Nifty! It's pretty sweet that they marked the audio, video, and ground pins on the circuit board. That's gotta be a time-saver! I'll keep your advice about removing the RF components and soldering together the X and Y syncs in mind. Anything I can remove from the television will make it smaller and lighter, in case I want to build a micro arcade cabinet or something. Thanks again! Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 27, 2013 Author Share Posted May 27, 2013 Ha ha! I've got the television cracked open, and indeed there are points on the circuit board marked AUDIO, VIDEO, and GND. Unfortunately, there are also points marked AFT, HD, and COLOR, along with VIDEO2. I'm not sure what these are supposed to do, but I suppose VIDEO and VIDEO2 could be the horizontal and vertical syncs. COLOR makes me wonder if there's a matching luma point that I could solder to, making it possible for the television to accept S-Video, but that's probably being much too hopeful. Quote Link to comment Share on other sites More sharing options...
Osgeld Posted May 28, 2013 Share Posted May 28, 2013 poke poke poke, the only way you will figure it out Quote Link to comment Share on other sites More sharing options...
Uzumaki Posted May 28, 2013 Share Posted May 28, 2013 Got an oscilloscope? You could poke and sniff out the signal, and compare to NTSC standard waveform. If it looks like Luma signal, it may be luma. Also have you tried searching Google for schematic or something? Once in a while there's free schematic that is for real. Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 28, 2013 Author Share Posted May 28, 2013 Haven't found one yet, but I did come up with the instruction manual, which offered some useful information. I've got wires connected to the AUDIO, VIDEO, and GND points, and will test it out as soon as I can get RCA jacks. I'm sadly out of them, and have been harvesting A/V cables from discarded TV Games units for my most recent projects. Maybe I'll have to hit up BG Micro for more, if it's still in business. Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 29, 2013 Author Share Posted May 29, 2013 Yahoo! I found a couple of RCA ports from what looks like a discarded sound card, and used those to test the project. The good news is that I'm getting video, and it's probably as good as it's going to get. This is passive-matrix, and it's never gonna look sharp no matter what... I'm just happy I've got a passable picture. Now for the bad news... connecting to AUDIO alone is giving me audio, but it's really lousy... harsh and full of static. I'm not sure what I can do about this, although using the same grounding point for both audio and video is probably not doing me any favors. I suppose throwing a resistor somewhere in the mix could help too, but I'm not certain. I'm not an electronics expert and do this stuff by the seat of the pants, so I couldn't say for sure what would fix this. Quote Link to comment Share on other sites More sharing options...
Osgeld Posted May 29, 2013 Share Posted May 29, 2013 yea it sounds like your overloading the amp's input, maybe a resistor in series with the input will help Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 29, 2013 Author Share Posted May 29, 2013 That did it! But the sound is a little soft now... I'll have to put two of the resistors in parallel to cut resistance in half. I really should have used a potentiometer first to dial in the right volume, but c'est la vie! Sadly, I lost video after another round of tweaking. Not sure if I lost the connection or what. I'm going to solder up a wire to VIDEO2 and try that, then combine them and solder them together. Even when I did get it working the first time, I still got the tuning line, and that wouldn't go away until I switched the television off and on. That was disappointing; after removing the RF modulator I thought that would stop happening. Quote Link to comment Share on other sites More sharing options...
Osgeld Posted May 29, 2013 Share Posted May 29, 2013 it did on mine, but that was a sony 1 Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted May 29, 2013 Author Share Posted May 29, 2013 I don't know what I did, but I'm not getting a video signal now, and nothing seems to fix the problem. Maybe the ribbon cable is damaged, maybe some solder was bridged on that tiny board, maybe I used too hot a soldering iron and something got damaged. I don't know, but I'm tired of soldering and I feel like the damned thing is mocking me with its refusal to work. So I'm probably done with this for a while. I'm disappointed and angry and I don't really need the aneurysm. Quote Link to comment Share on other sites More sharing options...
roxette Posted April 15, 2017 Share Posted April 15, 2017 Hi @Osgeld, I have the same device, i followed the instructions you posted on that link and soldered the composite A/V wires however i can't figure out which two pins on the LCD controller that should be soldered. Could you please help? Thx. Quote Link to comment Share on other sites More sharing options...
Osgeld Posted April 16, 2017 Share Posted April 16, 2017 its been a long time since I even thought about that thing and its long gone, but I think its just soldering pins 1&2 together of the M52042FP Quote Link to comment Share on other sites More sharing options...
roxette Posted April 16, 2017 Share Posted April 16, 2017 (edited) You are right, it has been 6 years since you did that mod I soldered pin 1&2 as you suggested but the problem wasn't solved. I get a picture for 3 sec then it shakes a lot till it disapperars with a lot of interference as if the tuner want to kick in although the tuner board is not plugged .... any other suggestion? Edited April 16, 2017 by roxette Quote Link to comment Share on other sites More sharing options...
roxette Posted April 18, 2017 Share Posted April 18, 2017 I want to plug the tuner board again to receive signal from rf modulator How i can have video output out of this thing? The RGB pins 10,11,12 can be used somehow? Quote Link to comment Share on other sites More sharing options...
Osgeld Posted April 19, 2017 Share Posted April 19, 2017 I dont know other than what I did, and like I said the device is long ago hit the bin Quote Link to comment Share on other sites More sharing options...
roxette Posted April 20, 2017 Share Posted April 20, 2017 I dont know other than what I did, and like I said the device is long ago hit the bin While reading your hackaday article, you wrote: Checking the schematics again Following the schematic Therefore, having the device or not isn't the issue. Nevermind, suggestions from other members are welcome. Quote Link to comment Share on other sites More sharing options...
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