tk3000

Iesposta: thanks for the clarification, I can now see that there is small white line going from the no. 21 to the right soldering point/pad and the soldering point itself seems to have a faint white circle around it. I believe that I have all soldering points properly connected now (the only doubt is about the J3 whereon I scraped the pcb mask to has access to the traces, but I believe I got the right trace that goes that respective J3 pad). Unfortunately whenever I try to read a cartridge it shows the same nonsense on the screen (blue screen with some meaningless blotted multicolored large thing and small thing that seems like the tank in the game combat) Moonsweeper: yeah, that is a very good point, having an ide like pin hole scheme would make much easier. Thanks for the insights!

By upper, do you mean pad closest to the joystick ports? That appears to be ground. The one closest to the epoxy blob, appears to come FROM the epoxy blob, so you would have to scrape the trace. ATARIAGE FOLLOWUP WITH FLASHBACK 2 ISSUES Sorry for not having catched the response before. The flashback2 I have has silkscreen with a table of corresponding values and has pads with numbers in the back of circuit board to as a reference for the cartridge connections, but the soldering pads/points are in different positions from the ones I saw on photos here on the forum, maybe I have different circuit board revision (hopefully mine is now a fake one). The following is a photo of mine with some indication: By upper pad I mean the soldering point pointed by a yellow line with a number 1 (pic above)., and I tested and there are indications that it may be a ground. The 1 and 2 marked numbered yellow lines ( added editing the image) are only to help visualize are equivalent to J3 on circuit board and they the ones I messed up and eroded the plated soldering point by overheating them, but I believe that I was able to scrape some of the mask of the circuit board trace and was able to solder it there (but not I am not 100% if I got the right trace). Another object of confusion for me is the soldering point/pad 21, it is pointed on the pic above by a yellow line and the no. 3. In my circuit board the silkscreen no. 21 is surrounded by soldering points so it is not clear to which soldering point does the no. 21 refers to. Thanks for any help

Hello Folks, I performed the mod, following the map the solering points/pads to a cartridge slot of an old non-functional atari2600 I had laying around. But I made a mistake of oversoldering the J3 pads and eronding them, so I tried to uncover the trace leading to such pads but I was not sure if I was accurate with the uppder pad. I would like to know if there is an alternative spot equivalent to the upper pad of J3 so that I could hook the wire there. thanks

Thanks, I guess I know that. It was for photo purposes, so that I could spread everything and it all could be seen. Old electronics tend to be much more resilient though, in a modern circuit board with sms ICs and billions of transistor per IC is a different story and I would not touch them without grounding myself often or having an anti-static wrist strap and certainly laying them in an non-conductive surface (cardboard works well)

Hello, I happened to have to built the same intellivision composite video mod with small variations, basically the same circuitry. I tried some of the suggestions present in this thread, such as changing the capacitors across the circuit from 100uF to 10uF with little or no difference, also change the 22ohms resistor a 40 or 50 ohms values produced worse results (more color and contrast bleeding), found a compromise around 33 ohms for this resistor. On the introduction screen of many mattel intellivision games the distortion and bleeding is more noticeble than on the games action screen. On standard definition crt tvs I notice a small amount of trembling of the whole screen (although small it is bothersome) but the otherwise is fairly good, such effect was not noticed on a high definition lcd screen but the distortion and bleeding is more saliented there . As suggested I tried to cut off the video signal going to the RF modulator and when I did so there would be no video feed on the circuitry board, I heard that disconnecting the RF modulator altogether would get rid of such video distortions. The use of bypass capacitor in my case did not help much (using 1000uF connected to grd and 5V rails) Any suggestion would be appreciated. Thanks, tk3000

I'm going off what people said in the "Items for Atari 2600 manufactured in Brazil" thread - http://www.atariage....ured-in-brazil/ I took a quick look atsome of the comments on the thread. I don't have a functional PAL-M console anylonger so I can not test NTSC cartridges on a PAL-M console. But I have SMS PAL-M console and equivalent cartridges, I can play it on my NTSC CRT TV but it is displayed black and white on the screen. Most Pal-M TVs in Brazil can actually recognize and negotiate a NTSC tv signal (and that has been the case for many years) One should also note the following entry made by Sr. Ferraz, fact that I was not aware of: "The carts were usually manufactured here in NTSC system, in consoles manufactured here existed a internal 'transcoder' (NTSC>>PAL-M)."

I'm going off what people said in the "Items for Atari 2600 manufactured in Brazil" thread - http://www.atariage....ured-in-brazil/ I took a quick look atsome of the comments on the thread. I don't have a functional PAL-M console anylonger so I can not test NTSC cartridges on a PAL-M console. But I have SMS PAL-M console and equivalent cartridges, I can play it on my NTSC CRT TV but it is displayed black and white on the screen. Most Pal-M TVs in Brazil can actually recognize and negotiate a NTSC tv signal (and that has been the case for many years)

Actually your games would work fine - your console won't work on an NTSC TV, but your games will run fine on a different console, I think PAL-M games will be identical to their NTSC equivilants as they have the same set of colours (I think a PAL-M console is just a NTSC console modified to use a different colour carrier). Thanks for the input. But I have a large library of Pal-M (my father used to work in Brazil when I was kid) cartrdiges and none of them seem to work either in my NTSC Atari 2600 or Atari 7800. At first I also tend to imagine that they should work more or less ok.

None of my PAL-M (M is for the specific brazilian PAL system which borderlines the NTSC system) games would play in a NTSC console. Below is an excerpt from Wikepidia related to the PAL-M tv and broadcast system: " PAL-M being a standard unique to one country, the need of to convert it to/from other standards often arises. Conversion to/from NTSC is easy, as only the colour carrier needs to be changed. Frame rate and scan lines can remain untouched. Conversion to/from PAL/625 lines/25 frame/s and SECAM/625/25 signals involves changing the frame rates as well as the scan lines. This is achieved using complicated circuitry involving a digital frame store, the same method used for converting between NTSC and the 625/25 standards. The fact that the colour encoding of PAL-M and PAL/625/25 is the same does not help, as the entire signal goes through an A/D-D/A conversion process anyway. "

Thanks for the all insight on how to address such issue. I planing to install a socket for the RIOT chip (also to avoid damage due to heat transfer). Compared to all the other boards and board revisions that I have seen so far this is by far the worse quality one in terms of quality of construction and assembly, and believe it or not it was made by the only Atari licensees in Brazil, the now defunct Polyvox (that was acquired by another consumer electronics company called Gradient). That board never went through repair, it came with all the soldered jumper wires from factory, and it is also missing the metal shield.

Hello, I have among other Ataris a Brazilian unit manufacturer in 1988. Which then uses the PALM video system/format. It is not working, if I insert the cartridge (palm cartridge of course) and it shows noise and static on the screen. I opened the console and it seems that the solder joint and soldering points at the RIOT is failing, apparently the circuit track whereon the solder is suppose to adhere is gone. Below is a pic of the: Any insight on how to best approach such issue would be appreciated.