xCoduster Posted July 28, 2015 Share Posted July 28, 2015 (edited) Hi, recently I found my dad's old TI-99/4A and when I try to start it I just get this: http://imgur.com/ZxugEAj. May dad says that he maybe broke a connector or something when he was trying to start it a few years ago, but I can't see any damage to the pins. Can someone please help? Edited July 28, 2015 by xCoduster Quote Link to comment Share on other sites More sharing options...
+mizapf Posted July 28, 2015 Share Posted July 28, 2015 Great multicolored graphics! ... or wait, is this just a reflection? So is this a black screen, or snow? Can you hear something from the speaker? Quote Link to comment Share on other sites More sharing options...
xCoduster Posted July 28, 2015 Author Share Posted July 28, 2015 The left side of the picture is the screen the rest is a reflection. I can't hear anything from the speakers. Quote Link to comment Share on other sites More sharing options...
globeron Posted July 28, 2015 Share Posted July 28, 2015 Check the TV channel (Channel 36, or check other channels, around 595 MHz ?) Is it an European Console? (Din-plug has 6 pins in total?) Maybe check the PAL-modulator? https://www.facebook.com/groups/2209774843/10153007017404844/ http://www.ti99.com/ti99r1.htm (in the metal box, you can change the frequencies, be very careful, as the black item (tuner) can break easily) and then maybe check other frequencies on the TV, maybe use fine-tuning ?) If it is an USA console (DIN 5 pins), then better get a cable with composite connectors Quote Link to comment Share on other sites More sharing options...
xCoduster Posted July 28, 2015 Author Share Posted July 28, 2015 Channel 36 is the only one with singal and it's frequencie is 591.25 MHz. The console says it's assembled in U.S.A but has six pins. 1 Quote Link to comment Share on other sites More sharing options...
globeron Posted July 28, 2015 Share Posted July 28, 2015 Are you based in Europe? 6 pin is EU Might be Pal modulator or check the.coax cable I had some issues with those. Have you opened the pal modulator? I removed the metal plate covering the channel selector do you.see any light blue or title screen related info on.the tv or lcd Quote Link to comment Share on other sites More sharing options...
globeron Posted July 28, 2015 Share Posted July 28, 2015 I just see you are in Sweden. My gut feel is the pal modular I had the same thing here but had two here so could compare. But suddenly both worked again. Not sure which pin are broken? Joystick port. Cassette port I o port. Module port. Video din port? Quote Link to comment Share on other sites More sharing options...
xCoduster Posted July 28, 2015 Author Share Posted July 28, 2015 I think it is the Video din port but it looks ok. Quote Link to comment Share on other sites More sharing options...
xCoduster Posted October 31, 2015 Author Share Posted October 31, 2015 This is my PAL Modulator http://imgur.com/BwCydsiit's a PHA 2036. Quote Link to comment Share on other sites More sharing options...
xCoduster Posted October 31, 2015 Author Share Posted October 31, 2015 After a while the screen goes black and then it blinks white and white lines goes over the screen. Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted October 31, 2015 Share Posted October 31, 2015 After a while the screen goes black and then it blinks white and white lines goes over the screen. Let's do a little diagnosis first before we go any further... 1) Is the picture stable at first? 2) Does it degrade AFTER the computer warms up... (usually a predictable time interval)? If so, let's isolate which device is causing the problem. 1) Turn on the TI WITHOUT the RF modulator plugged in, and let it set for the time it usually takes to go bad plus a few extra minutes. 2) Now plug in the RF modulator. Question: Is the image ALREADY bad, or is it stable? If it's stable the modulator is probably the culprit, if it's instantly bad, the TI is probably the issue. Now we can focus on what course of action to take. 1 Quote Link to comment Share on other sites More sharing options...
ti99iuc Posted October 31, 2015 Share Posted October 31, 2015 (edited) Hello xcoduster the Black Screen is very common in the TI-99 ... is not a single thing as problem and it could be any. you could try to build a simple Cable with composite signal, but because it will be a PAL version of the TI99 you will be found an image in B/W, the cable could just help you to see if the TI screen appear on the TV or a black screen again will be. and fo some other kind of modification of the modulator you can try also to this link: http://www.ti99iuc.it/web/index.php?pageid=119&pagina=mod_proj1&sezione=4&data=Mod_and_Tuneed just it is possible that is not the modulator broken, maybe the ti99 Motherboard is the problem, Xad Nightfall has repaired all my 15 TI99 and lot of them had black screen. you can check at his website for have some suggestions on the problem of your TI., at THIS link. Edited October 31, 2015 by ti99iuc Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted October 31, 2015 Share Posted October 31, 2015 If the problem is on the PAL-Modulator I could send you one for free. Just let me know. Quote Link to comment Share on other sites More sharing options...
xCoduster Posted October 31, 2015 Author Share Posted October 31, 2015 Let's do a little diagnosis first before we go any further... 1) Is the picture stable at first? 2) Does it degrade AFTER the computer warms up... (usually a predictable time interval)? If so, let's isolate which device is causing the problem. 1) Turn on the TI WITHOUT the RF modulator plugged in, and let it set for the time it usually takes to go bad plus a few extra minutes. 2) Now plug in the RF modulator. Question: Is the image ALREADY bad, or is it stable? If it's stable the modulator is probably the culprit, if it's instantly bad, the TI is probably the issue. Now we can focus on what course of action to take. 1) No 2) The screen goes black and white lines drops down from the top when it has warmed up The image is already bad. Quote Link to comment Share on other sites More sharing options...
xCoduster Posted October 31, 2015 Author Share Posted October 31, 2015 I tried to start the TI-99 without the RF Modulator and now I get this http://imgur.com/rYVkjUL Quote Link to comment Share on other sites More sharing options...
Stuart Posted October 31, 2015 Share Posted October 31, 2015 With the DIN connector on the 'computer end' of the modulator cable, you should be able to slide the plastic sheath back (might be a metal tab that you have to push back into the connector slightly) and separate the two halves of the connector shell. You can then check if any of the signal cables has broken from the connector pin. Also look at the connector pins and check if they are badly tarnished so not making a good connection. Might be the case if the computer hasn't been used for years. If you've got a multimeter then I can tell you which pins to test to check that you've at least got power getting to the modulator board. Stuart. Quote Link to comment Share on other sites More sharing options...
xCoduster Posted October 31, 2015 Author Share Posted October 31, 2015 Yeah I got a multimeter Quote Link to comment Share on other sites More sharing options...
xCoduster Posted November 1, 2015 Author Share Posted November 1, 2015 Wich pins should I test? Quote Link to comment Share on other sites More sharing options...
Stuart Posted November 1, 2015 Share Posted November 1, 2015 xCoduster, on 01 Nov 2015 - 09:32 AM, said:Wich pins should I test? If you put the box as you had in your photo earlier, with the cable on the left and the silver Astec modulator on the right. There is a group of 4 ICs on the PCB. The bottom right IC should be labelled LM1889. Check the voltage between the 5th pin down from the top left of this IC(-ve) and the pin directly opposite that on the right hand side (+ve). You should get around 12V. Also, are you testing this on a 'modern' TV or an old analogue one? The modulator output frequency may well have drifted over the years and a modern TV won't lock to it, but an old analogue one will. Stuart. 1 Quote Link to comment Share on other sites More sharing options...
xCoduster Posted November 1, 2015 Author Share Posted November 1, 2015 I get 11.67 Volts on those pins. I tested the machine on 2 modern TV's and I got the same result with blurry screen and a long beeping sound. But booth of them lock to the right frequency. Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted November 1, 2015 Share Posted November 1, 2015 << THIS >>is a possible solution for your consideration, if you have a spare VGA monitor laying around the house. It's been known to fix a myriad number of problems with many peoples video outputs. No endless diagnosis, no un-soldering and re-soldering, no trial and error, etc. The results are awesome too! Quote Link to comment Share on other sites More sharing options...
xCoduster Posted November 1, 2015 Author Share Posted November 1, 2015 I'm not so good at electronics so I just wondered where I should connect the board to the TI-99/4A Quote Link to comment Share on other sites More sharing options...
Opry99er Posted November 1, 2015 Share Posted November 1, 2015 Use an IC puller or small flat blade screwdriver to pull the TMS9918A chip. This drops right in in its place. Quote Link to comment Share on other sites More sharing options...
Omega-TI Posted November 1, 2015 Share Posted November 1, 2015 .. where I should connect the board to the TI-99/4A That is where the F18A REALLY SHINES! It's PLUG-N-PLAY, and comes with easy to follow instructions, so if you have a Phillips screwdriver, you can do this project. I did a blog entry on this item a while back, << CLICK HERE >> if you want a little more information. 1 Quote Link to comment Share on other sites More sharing options...
Stuart Posted November 1, 2015 Share Posted November 1, 2015 I get 11.67 Volts on those pins. I tested the machine on 2 modern TV's and I got the same result with blurry screen and a long beeping sound. But booth of them lock to the right frequency. If it's beeping from the moment you apply power to the moment you switch if off, that's a console problem - it's not booting and the sound generator isn't being switched off. First thing you could try is strip down the console (see [http://www.mainbyte.com/ti99/console/console_dis.html] if you're not sure how to) and remove/reseat the 6(?) socketed chips. That might just sort it. If that doesn't help, then might be easiest to get a 'new' console off ebay. Quote Link to comment Share on other sites More sharing options...
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