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Dopy25

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Posts posted by Dopy25

  1. On 8/30/2022 at 6:35 AM, -^CrossBow^- said:

    On the flickering I had another thought and question though. Does it flicker when you press the fire button by chance?

     

    Out of curiosity, what would it mean if it flickers when you press the fire button? Is that an issue, or a common feature bug?

  2. 3 hours ago, TimC said:

    So coincidentally, I also have an older 520STM motherboard.  I saw this upgrade on Adrian's Digitial Basement so I thought I would try it out.  I ordered the boards and actually found an old 72-pin 4MB SIMM with 2 of those chips on there.  I desoldered them and resoldered them on to the Atari memory board.  I need to work up the courage to desolder all the ram on the Atari ST and install this guy.  I may even use a switch for the A9 address line.  I will let you know how it goes.

    Awesome. Mine went well. Take it slow with the ST ram chips. Best way I found was to lay the board flat, and use a heat gun from the bottom. I have a pair of angled tweezers that I set under the ram to let the tweezers do the work once the solder was hot. The light weight of the tweezers will pop the ram up. After that you can use a desoldering unit to pull the solder out. Luckily you only have to clear the top 2 rows holes for all but 2 slots. 

     

    I chose not to use a switch for a9 because I don't even know what software malfunctions with 4MB vs 1MB yet. It's all new to me. When I can find a piece of software that causes an issue, I will decide at that time. Everything I am running is from masteries SD card solution right now and I think anything that runs from SD has already been modified and will most likely work with 4MB.

     

     

    The issue in my last post was interference. Every board worked well after I moved the MMU lines away from whatever was causing it not to boot. It had to be too close to one of the other connections on the board somehow. 

    I posted more about it under hardware:

     

     

     

    • Like 1
  3. It's hard to believe I am the first to leave feedback in this sub forum for this seller. I've seen so many positive comments in masteries sales threads.

     

    I picked up a low cost SD card solution for my Atari 520ST and it is amazing. Mine was basic so I had to upgrade the RAM before I could play most of the software, but after upgrading the onboard ram from 512k to 4MB, it runs like a champ.

     

    masteries is great if you have any questions. He helped me pinpoint a few issues I was having that were unrelated to the device but caused it to have issues for me. 

     

    Even the shipping was pretty good considering the location. He in Spain, I in the US. I am sure this is all dependent on the time of year as well so be aware.

     

    I would not hesitate to buy anything from masteries in the future.

  4. Update: I have 2 left.

    Update: last 2 are pending

     

    ALL SOLD

     

    I only needed one, but since 5 boards was the minimum order, I bought enough to make 5. I figured instead of throwing away 4 blank boards, I would buy enough RAM and SMD components to finish all of them and part with the rest. I won't do it again so the 4 remaining are up for grabs and that's it. All have been tested in YAART. If you have a preference on how many passes you want me to run, I will redo it. Just let me know.

     

    This board will provide your Atari 520ST (an possibly others with a similar 512k layout) with 4MB of ram, or 1MB if you ground the a9 line. You can also use a switch to change between 1MB and 4MB. That would be on you to figure out. 

     

    This board was designed by agranlund and the PCB was posted on his GitHub. You can build your own if you have the patience and knowledge. This particular board design was "fixed". By a user (snarkdluG on AA) and posted in a thread here on AA. It does not require a bodge on the ram board, and the CAS & RAS solder points are correctly labeled. They are swapped on the original design. 

     

    You must remove your old RAM and put this board in their place. You cannot use sockets as it will not provide enough clearance for the RF or keyboard to sit inside the case. Feel free to Frankenstein it if you want but I warned. 

     

    Not all pins are required to be soldered in place. It is labeled as such on the board. Therefore only 2 boards have 2 rows of pins across the top, and 2 have pins only where a connection is needed. You may also need to remove the header pins for the lines that go to MMU. They were there for testing.

     

    Feel free to specify which you would like (until I only have one style left)

     

    Cost is $35 plus shipping on PayPal.

    If you can send Venmo friends & family payment, cost is $30 plus shipping. 

     

    Please feel free to ask any questions. 

    PXL_20220901_223803343.jpg

    PXL_20220901_223749255.jpg

    PXL_20220901_213712101.jpg

  5. 56 minutes ago, -^CrossBow^- said:

    Ah I appreciate you checking on that. I was mainly bringing it up because I wanted to make sure that if you had any potential buyers for it, that Cozmo would still do all the functions he initially would. Again, in the case of the newer Vector, it requires the sub service to get the fully functions out of him again. I need to setup a large empty box for my Vector and see if he starts doing anything more than sit there looking into space... He was so cool when the voice and other services did work though.

     

    No problem at all. I'm glad you asked. Maybe a potential buyer had the same concern. I remember when we got Cozmo. He was such a blast. But kids grow up and have the attention span of a goldfish these days. Honestly if I can find a way to trade someone anything else for a PS4, I'd trade my son for Cozmo just to keep him. haha

  6. @-^CrossBow^-

    I was finally able to get my son to spend some time testing Cozmo. I told him someone wanted to know, and that he should do it sooner than later but since it's his, I didn't push too hard.

     

    Cozmo works fine without any sort of internet connection and we do not have a subscription. He picked up a cube and enjoyed it for a few minutes it before my son put him back in the box. No subscription, no issues.

     

    I can send you a short video of him working and playing if you like. 

  7. 1 hour ago, pepeart said:

    The flickering its gone, I cleaned the cartridge slot and the flickering its gone. My picture its still dark even after adjusting the colors. I just notice that when I first turn on the Atari the picture its normal for a couple seconds, than it darkess. Since the 75ohm resistor was not installed, I might need it for my set up lol. 

    Or you might need to replace some capacitors.

     

    I know there are some green "chiclets" on the board that are responsible for video clarity. 

     

    https://console5.com/store/22uf-100volts-film-capacitors-5-atari-chicklet-replacement.html

     

    Hmm. It says they're responsible for RF interference. I guess those might not be the issue but it might be worth looking into.

    • Thanks 1
  8. 15 minutes ago, Bee said:

    So to make the upgrade you remove the old ram and make connections to the MMU?

    Yes. Remove all the old RAM and solder the board in their place (most of their place), and you make 4 connections to the MMU.

  9. SUCCESS!!

     

    The issue was the routing of the wires to the MMU. Something interfered with them. Not sure what it was but I had an idea to move the wires away from the edge and to again so I placed a spacer between the board and cabling and tried again and it booted! 

     

    The other 3 assembled boards also work. 

    PXL_20220830_220918801.jpg

    • Like 3
  10. 9 hours ago, Stephen Moss said:

    I found a parts list where C36-C39 are listed as 0.22uf (220nF), 25V Ceramic axial, if you have any 0.1uf you could put two in parallel to get 200nF.  

     

     

    I did have those. Unfortunately adding that in made no change. It's still pink and black bars only.

     

    I even tried a third set of board/chips with the exact same outcome. This board had never been installed, and the pins never bridged, or at least powered while bridged. At this point I'm wondering if I have the wrong chips. It's odd to me that they would all have the same outcome.

     

    Guess I'll try to revert everything unless there are other ideas. I'll be looking for replacement chips in the meantime.

     

    Thanks for the advice. 

  11. It did in fact work before the mod, yes. The issue is that I started by clipping the legs off the old RAM chips before remembering I could use my heat gun. Hence the overheating in the middle of the rows of RAM chips. 

     

    I suppose I could remove the 6 pin sockets and install full sockets, and buy more RAM, but I think that would be more work than I want to do, considering it *did* work before any modifications. Although if I can't figure anything else out, I guess that will be my only option 🤷🏼‍♂️. Ugh. 

  12. Looks like they should be 220nF based on the 224 above what you can see in the pic.

    The whole label reads:

    CGW
    224
    Z5J
    8327 (OR 8321)

     

    Looking up this info it seems the most likely is 220nF. Unfortunately I do not have this value or anything remotely close to it. Looks like I will order a few and hope any extra eyes will help in the meantime.

  13. Here are a few more pics of the Atari board. 

     

    I'm still not sure those old ceramic caps are necessary but can anyone tell me what would be an acceptable replacement for the caps located at c36, c37, c38? When I first tried to remove the old chips, I used too much heat in this area and burned the old caps. One even fell apart. I didn't think they were necessary because the positive side no longer comes into contact with the new pins but I could be wrong. I double checked continuity in this area as well and everything still seems ok. 

     

    Also uploaded a pic of the caps that I put too much heat on. 2 have the same label (3127) but the third ends in 3121. I don't know the difference and I can't seem to find a component list that includes c36-c38.

     

    PXL_20220829_221708761.jpg

    PXL_20220829_221809076.jpg

    PXL_20220829_221902531.jpg

    PXL_20220829_222245360~2.jpg

  14. Here are some pics of the board and RAM. 

     

    After checking the diagram for this ram, I'm pretty sure I did not bridge vcc. I think I bridged pins 2&3 on one chip and somewhere around 15-17 (not all pins, just 2 of them) I could also be mixing it up as I didn't take notes on which were bridged, not even mentally. I just was kinda like "oh those shouldn't be there" and used a wick to get rid of it. I guess I could have bridged the other side and maybe it was around pin 37 which says it's VSS. I'm guessing that might not be a good thing either. 

     

    I do have 2 boards that are not fully assembled yet, and 4 chips that have been completely unused. I'll finish assembling them and check for bridged pins before supplying power this time. It's just kinda weird to me that they all have the same result so far with those pink and black bars. 

    PXL_20220829_161932574.jpg

    PXL_20220829_161957233.jpg

  15. On 8/27/2022 at 11:52 AM, Leonard Smith said:

    I'm not certain, but this *could* be an El Paso or very early 7800 variant.  


    I'm basing my assessment due to the fact that the rainbow stripe color is the early one with the red, orange, yellow striping.  I think I'm also seeing a 1984 version of Pole Position II, so perhaps it's part of the set.


    I've contacted the seller to see if I he can provide the serial #, but no response as of yet.

     

    https://www.ebay.com/itm/265849686371?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=FlU0dTJDS2m&sssrc=2047675&ssuid=8Q6gleWtSSW&widget_ver=artemis&media=COPY

     

     

    Holy crap are the EP units really worth $500? 

  16. 3 hours ago, Stephen Moss said:

    Well it is possilbe but it really depends on what (if anything) was shorted to where, but you are more liekly to damage the RAM chips but putting them in the wrong way round, particualry if that reversed power pins so VVC goes the the GND pin.

     

    Does it produce the same image with no RAM chips in?

    Deen a long time since I dived into/had an ST, if I recall corectly from fitting my Marpet RAM upgrade the MMU is the 4 sided surface mount device and it is very easy to misscount the pins and connect to the wrong one (as I did) or short a couple of pins together when soldering.

    I will post a picture of the board. I don't think the ram is soldered on backwards but I will post before I try another one so I can get more eyes on it. I am sure I matched pin 1 to the right dot on the board.

     

    It shows nothing on screen with no ram chips installed.

     

    I can't remember which ones were bridged at this time or I would absolutely note that. I will look at them again and compare with the diagram to see if anything jogs my memory. 

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