STeSearcher Posted February 18, 2021 Share Posted February 18, 2021 I have an old "beater" 1200XL which I have decided to upgrade with various things. It does seem to work. When I fired it up after years of storage, the Atari rainbow logo came up but was weak and the color was washed out. I had purchased a UAV before and installed it last night, double checking the joints, etc. So now I have a stronger signal but still somewhat dim and the color is poor and fuzzy. Any ideas? Quote Link to comment Share on other sites More sharing options...
TGB1718 Posted February 18, 2021 Share Posted February 18, 2021 What are you using to display the picture, RF, Composite, S-Video ? Maybe a screenshot of how it looks too Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted February 18, 2021 Share Posted February 18, 2021 Photos of the output and of your work would really help. I’ve got UAV’s in two of my 1200XL’s and they look great. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 18, 2021 Share Posted February 18, 2021 check the UAV itself for cold solder joins/ points, make sure it's seated in the socket properly and if 4050 is still present that it's clean and seated as well, or if soldered to the chip, same deal about joints.. make sure the video cable is good, monitor adjusted Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 18, 2021 Author Share Posted February 18, 2021 (edited) I reflowed a couple of the connections and had to bodge one of wires after screwing up the trace. Still looks the same. (edit: I'm using a Atari monitor cable with the composit yellow wire connected to a Dell multisync monitor that does the right refresh rate. It works fine with my Mega STE.) Edited February 19, 2021 by STeSearcher Quote Link to comment Share on other sites More sharing options...
manterola Posted February 19, 2021 Share Posted February 19, 2021 Color pot? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted February 19, 2021 Share Posted February 19, 2021 Well, your jumper configuration looks okay, and that does look like you've got the Composite output running to the correct inductor. pad A little puzzling why you didn't run the Luma output to the adjacent inductor pad instead of running it to the bottom of the board (DIN pad connection?). I know Chroma has to go directly to the DIN anyway. The only oddity is that you seem to have run a separate GND connection to the leg of that resistor. There's no need to do that - the UAV gets its GND from the 4050 socket when installed there. The only thing to be sure of is that you've soldered the Chroma and Luma connections to the correct points under the DIN jack. It looks like you're overdriving the signal - if you've got Composite going in through the lifted inductor pad and are accidentally feeding the same pin with the Luma or Chroma signals, you could overdrive the output. You could also remove that superfluous GND wire from the terminal block but I doubt that would make a difference. Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 19, 2021 Author Share Posted February 19, 2021 I ran the the Luma to the underside due to the pad lifting off. I have checked them again and removed the extra ground and no change. Puzzling. I have been soldering on retro stuff since the early 80s so it's not like I haven't done it. Last year I recapped my Mega. It does look overdriven with color ghosting left and right of the image. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted February 19, 2021 Share Posted February 19, 2021 My 3 hours ago, STeSearcher said: I'm using a Atari monitor cable with the composit yellow wire connected to a Dell multisync monitor Okay, so let me ask you this: what kind of "Atari monitor cable" are you using? The reason I ask is, modern repro DIN-to-RCA cables don't really follow the traditional standard of "Yellow=Composite, White=Left Audio, Red=Right Audio". So it can be hit or miss which color RCA jack is actually carrying the Composite, which one is carrying Chroma, Luma or Audio. Does the monitor you're using have any other inputs? Or do you have any other TV or display with a Composite input you can test with? 1 Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 19, 2021 Share Posted February 19, 2021 (edited) yeah it looks like the wrong signal being supplied... I bet the cable is not following the standard... it was common for cables that fit the Atari to be used with it but the pin outs being incorrect often crossed the signals or simply put the signal on the wrong colored RCA jack/plug. Most of them were use able but you had to re label the RCA side of things Edited February 19, 2021 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
StickJock Posted February 19, 2021 Share Posted February 19, 2021 13 minutes ago, DrVenkman said: "Yellow=Composite, White=Left Audio, Red=White Audio" Ooooh, Algebra! W=L and R=W, therefore, R=L. Exactly what one would expect on a non-stereo, 1979 mono system! ? Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted February 19, 2021 Share Posted February 19, 2021 2 minutes ago, StickJock said: Ooooh, Algebra! W=L and R=W, therefore, R=L. Exactly what one would expect on a non-stereo, 1979 mono system! ? Typos ... d'oh. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 19, 2021 Share Posted February 19, 2021 (edited) I have a cord where where black on the cord is yellow on the monitor, white on cord is audio on monitor, red on cord is luma, and yellow on cord is chroma. That's 4 plugs on one cord and the only one even close to what you would thing was correct is the white cord in the scheme of things... so that's what Dr.Venkman means.. Edited February 19, 2021 by _The Doctor__ Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted February 19, 2021 Share Posted February 19, 2021 My guess is that you are driving a COMPOSITE signal that has no or little CHROMA into the monitor's COMPOSITE input. The monitor is trying to normalize the color burst by turning up the gain in the color separation circuits. The problem is not enough signal, not too much. The LUMA input on your monitor will not react to the color burst signal. Can you try that? You should fix your 1200XL before you add the video upgrade. If it looked bad before, it must be in the video circuits or cables on the 1200XL, right? A 'beater' 1200XL? Never met a 1200XL I didn't like... Bob Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 19, 2021 Author Share Posted February 19, 2021 I think I got this cable from Amazon quite some time ago. I took it apart and I think the luma signal was on the composite pin....I changed it and now it looks better. Not as better as some of the images I have seen but lots better than before. Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 19, 2021 Author Share Posted February 19, 2021 I should have investigated the output first, true. But I was wanting to install the upgrade so I got ahead of myself. It turned out to be the cable anyway. I said beater since I have a 99% 1200XL still in the box. This was a "used for parts" one I got years ago. Turns out they didn't test it at all. I love the 1200 and wanted a modded one but didn't want to use the really nice one. My first computer was a 800XL bought on clearance from Sears back in 1982. I eventually made a detached keyboard, internal modem and new case for it. Sadly, it's long one now. 9 hours ago, bob1200xl said: <You should fix your 1200XL before you add the video upgrade. If it looked bad before, it must be in the video circuits or cables on the 1200XL, right?> <A 'beater' 1200XL? Never met a 1200XL I didn't like...> Bob 1 Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted February 19, 2021 Share Posted February 19, 2021 19 minutes ago, STeSearcher said: I took it apart and I think the luma signal was on the composite pin That was pretty common in the early days - early monochrome monitors often used RCA connections like that which carried only the Luma signal. So it was probably a cable meant to connect an Atari to a green or amber screen. Anyway, glad you got that sorted out. 1 Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 19, 2021 Author Share Posted February 19, 2021 Oops, just realized I had a 9v DC supply on it instead of 9v AC. Quote Link to comment Share on other sites More sharing options...
_The Doctor__ Posted February 19, 2021 Share Posted February 19, 2021 Bottom line, fixed cable, correct supply and your 1200XL is now fly... enjoy the machine! Quote Link to comment Share on other sites More sharing options...
STeSearcher Posted February 19, 2021 Author Share Posted February 19, 2021 Thanks to everyone! 1 Quote Link to comment Share on other sites More sharing options...
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