+9640News Posted January 22, 2019 Share Posted January 22, 2019 I noticed this issue last spring, and this past weekend, switched things around to confirm. I am not seeing red on my Geneve. Has anyone ever observed a specific color missing to know the likely cause? I pulled up John Strain's schematic from the 9938 to the video port, but have not started testing anything with an ohm meter to see if there is a break in connection yet as I have to find my ohm meter. Any thoughts on a likely failure? I do not know if the video lines run on a layer below the surface, or if they are visible. Any thoughts appreciated. Beery Quote Link to comment Share on other sites More sharing options...
+mizapf Posted January 22, 2019 Share Posted January 22, 2019 Cable OK? Solder joints on the board OK? I had that issue now and then until I made a completely new cable. Quote Link to comment Share on other sites More sharing options...
+9640News Posted January 22, 2019 Author Share Posted January 22, 2019 Two completely different cables. I will be testing solder joints once I find my meter. Beery Quote Link to comment Share on other sites More sharing options...
+InsaneMultitasker Posted January 22, 2019 Share Posted January 22, 2019 Is the video jumper near the neck of the card set to the right position? Quote Link to comment Share on other sites More sharing options...
+9640News Posted January 22, 2019 Author Share Posted January 22, 2019 Is the video jumper near the neck of the card set to the right position? I will have to investigate. I looked for a video jumper the other day when I was swapping/testing eproms for Mike, but did not see a jumper. Guess I need to take another look. Beery Quote Link to comment Share on other sites More sharing options...
+Schmitzi Posted January 22, 2019 Share Posted January 22, 2019 Hi, here are some infos I´ve gathered together over the time, for the jumper settings have a look at page 3. GENEVE-9640-&-TI-99-4A-&-MONITORS-PINOUT-v16c.pdf 1 Quote Link to comment Share on other sites More sharing options...
+9640News Posted January 22, 2019 Author Share Posted January 22, 2019 Thanks for the information. I guess I will have to squint a bit more to confirm the pin selection. As this Geneve was given to me something like almost 5 years ago, I assumed it had been properly configured since it was an RGB monitor that was being used. In hindsight, that may have been an error on my part and the previous owner may have had it improperly configured for all these years. I will know the answer in about 4 hours..... Beery Quote Link to comment Share on other sites More sharing options...
+InsaneMultitasker Posted January 22, 2019 Share Posted January 22, 2019 I will have to investigate. I looked for a video jumper the other day when I was swapping/testing eproms for Mike, but did not see a jumper. Guess I need to take another look. Beery It's close to the 8 pin DIN and easy to miss. Hopefully that's all it takes to resolve. Quote Link to comment Share on other sites More sharing options...
+9640News Posted January 23, 2019 Author Share Posted January 23, 2019 Thanks everyone for the comments. Turned out, it was just a dip switch set to composite instead of RGB. Beery 5 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 19, 2019 Share Posted March 19, 2019 (edited) Does anyone know of a reliable source to purchase a couple of 9938 video chips. I bought one from china a few months ago, and believe that I documneted a failure here on atariage concerning it. But that chip I believe caused a new ram chip to go bad and even after replacing the ram chip the 9938 is showing artifacing all over the screen. But when I put a known good 9938 onto the board the artifacting is gone. All the ones I see on ebay are from china, so does anyone know of a source here in the states? Thanks Edited March 19, 2019 by RickyDean Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted March 19, 2019 Share Posted March 19, 2019 Maybe Jim Fetzner will chime in here. He can tell you what to look for in a genuine chip online. 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted May 13, 2019 Share Posted May 13, 2019 Well, I bit the bullet and purchased two more 9938's from China, 1 came in Friday, waiting for the other. But that being said, the one that came in Friday is not operational, and I expect that the one coming in behind it will be no different. They were both purchased from the same seller on ebay, but not the seller that the prior bad 9938 was purchased from a few months ago. If this next one does not work, I will attempt to modify a 9958. Quote Link to comment Share on other sites More sharing options...
+helocast Posted May 13, 2019 Share Posted May 13, 2019 Well, I bit the bullet and purchased two more 9938's from China, 1 came in Friday, waiting for the other. But that being said, the one that came in Friday is not operational, and I expect that the one coming in behind it will be no different. They were both purchased from the same seller on ebay, but not the seller that the prior bad 9938 was purchased from a few months ago. If this next one does not work, I will attempt to modify a 9958. Slightly OT, but did you pay (or is anyone else) pay premiums (tariff increase or actual customs fees) on China orders lately? Jameco, Digikey, and a few others charge up front, but so far Ebay hasn't tagged me though I try to keep restock orders on my parts bins under $100 actual value. Just curious. Doug Quote Link to comment Share on other sites More sharing options...
RickyDean Posted May 14, 2019 Share Posted May 14, 2019 Slightly OT, but did you pay (or is anyone else) pay premiums (tariff increase or actual customs fees) on China orders lately? Jameco, Digikey, and a few others charge up front, but so far Ebay hasn't tagged me though I try to keep restock orders on my parts bins under $100 actual value. Just curious. Doug Sorry for the delay, helocast. No so far I have just made offers or paid the price listed on Ebay. I too, have paid some surcharge to Jameco, but not Mouser as of yet. Haven't done any business with Digikey recently. My question is why does a chinese seller, sell a product that will not work from the moment it is installed, where is the financial gain from that when I am just going to ask for my money back. I have waited patiently for this to arrive, just to discover from the get-go, it is worthless. Quote Link to comment Share on other sites More sharing options...
RickyDean Posted February 24, 2020 Share Posted February 24, 2020 Well, I finally found a 9938 on ebay from an usa seller, and when I installed it, my Geneve came up without artifacts, just need to get the drive reinstaled tonight and see if it boots fine. 6 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 5, 2020 Share Posted March 5, 2020 I was able to obtain two more good V9938's so I can start working on my other Geneve's now, Happy... Happy...? 2 Quote Link to comment Share on other sites More sharing options...
+dhe Posted March 5, 2020 Share Posted March 5, 2020 What was the seller name of the good 9938? Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 5, 2020 Share Posted March 5, 2020 2 hours ago, dhe said: What was the seller name of the good 9938? Dan, no it wasn't. Quote Link to comment Share on other sites More sharing options...
+dhe Posted March 5, 2020 Share Posted March 5, 2020 Let me try again, if one needs to buy working 9938's where does one go? ? Quote Link to comment Share on other sites More sharing options...
+Ksarul Posted March 5, 2020 Share Posted March 5, 2020 @dhe, finding a seller with good 9938s is a matter of luck. The last ones were working pulls, and all came from a single source (who doesn't have any more available at the moment), but the userID is: gameboardsoc1234. 1 Quote Link to comment Share on other sites More sharing options...
+dhe Posted March 6, 2020 Share Posted March 6, 2020 I guess given my own recent issue with cc-40 memory upgrade chips and what I'm reading in a number of threads on this forum... When getting CFC (Chips from China) to attempt a repair, one should take each chip with a grain of salt and either check it in a working unit or in a tester, before trying to use it in a repair to save hair pulling.... Getting a sealed and tested chip from Newark is now a thing of yester year.... =( 2 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 6, 2020 Share Posted March 6, 2020 12 hours ago, dhe said: Let me try again, if one needs to buy working 9938's where does one go? ? Oh, I'm sorry Dan, I was getting ready to leave work and go home in rain and storm, so wasn't thinking about that. If you need one badly, I can let you get one of mine? Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 6, 2020 Share Posted March 6, 2020 32 minutes ago, dhe said: I guess given my own recent issue with cc-40 memory upgrade chips and what I'm reading in a number of threads on this forum... When getting CFC (Chips from China) to attempt a repair, one should take each chip with a grain of salt and either check it in a working unit or in a tester, before trying to use it in a repair to save hair pulling.... Getting a sealed and tested chip from Newark is now a thing of yester year.... =( Yea, and I am also thinking some from China may be rebranded v9958's but haven't tried to wire on up yet to see, but they don't work as 9938's that their labeled as. Quote Link to comment Share on other sites More sharing options...
GDMike Posted March 6, 2020 Share Posted March 6, 2020 I'm having to test my 32K SRAMs.. finding not all are ok. 1 Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted March 6, 2020 Share Posted March 6, 2020 Unicorn Electronics has good chips that work first time, every time. Their minimum order (for free shipping) is $30. If you need a very small order, they are also HODGE16 on eBay. The prices are a bit more but they will combine shipping charges if you ask. Quote Link to comment Share on other sites More sharing options...
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