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These are now sold, thank you for anyone interested. Collection of spare ICs, and NOS GTIA. Looking for $80 + shipping from Los Angeles. I sold my beloved 400, and forgot that I had bought these. Please let me know if you are interested. Thanks. KB

Hi, some years ago I gave a promise to an ABBUC member to make a video-out solution for his Atari 400 without the need of changing parts, scratching conducting paths or any other destructive mod to his Atari 400. He´s a real "hardcore" collector with no way in give-and-take regarding this point. After tinkering around with an "add-on" PCB for the GTIA socket I failed, because there´s not enough space. Of course - from a collector´s view - it´s a No-Go to remove the metal cabinet, so I decide to create a complete new CPU board with the needed components directly on it. I´ve reached the goal by 99%. A very little bit of soldering is required and the need to drill one hole into the metal assembly - the shielded video cable needs a place to break out, there´s no way else than making a new 5 mm hole somehwere in the upper part of the metal assembly. So here´s my solution: The Super Color CPU Card for Atari 400 and Atari 800 systems This PCB is a complete replacement for the original CPU card in any Atari 400 or 800 using PAL or NTSC. This PCB works NOT with SECAM. You are able to use both CPU-types found in the Atari 400 and Atari 800 series, the standard 6502B MOS CPU (without HALT signal) and the Atari-specialized version 6502C, also called "Sally". Chips (CPU, ANTIC and CTIA or GTIA) are not included and must be pulled of the built-in Atari CPU card. But they are always in sockets, so it´s easy. Circuitry on this PCB is nearly 100% the same like at the genuine Atari CPU card with some changes to make it possible to use both CPU types. You only need to set five jumpers to select the desired CPU type. Addiitonal the PAL color clock generation circuit is onboard for PAL systems. There´s a seperate jumper to select PAL or NTSC - this jumper connects the GTIA "PALC" pin to either the output of the PAL color clock generator or directly to 3,57 MHz system clock (NTSC). Only for clarifying this: You can´t just switch the jumper and make a NTSC system to a PAL computer or vice versa. At least you´ve to change ANTIC, GTIA and of course the system clock crystal at the mainboard At least a third jumper block (not existing an the prototype shown on the picture above) enables/disables the 75 Ohm termination resistors for Luma, Chrominance or CVBS output. This setting must be tested depending on the connected monitor or television - sometimes the picture quality is better with, sometimes without termination resistors. The video out solution is based on the Atari 800 XL video circuitry without mixing Luma and Chroma together. Of course the well-known mods are already integrated. The final signals are amplified and filtered by the Fairchild FMS6410 VideoAmp. This chip also generates the CVBS signal. So you can use either S-Video (Y/C) for best picture quality or CVBS for common monitors and televisions which doesn´t accept S-Video (Y/C) input. Please notice: This video solution can´t performing magic. I test it on different computer monitors and televisions. The best performance - as ever in every setting with old computers - will be shown on CRT (tube) monitors or televisions. Of course for Atari 400 owners EVERYTHING is better than the antenna (RF) output, but don´t expect a higher quality than the regular Atari 800 S-video output. It might be better, but I can´t promise. That´s impossible by the dozens of different monitors, cables, T.V. systems and so on. Scope of delivery One PCB "Super Color CPU Card" for Atari 400 or Atari 800 computers, capable using 6502B or 6502C CPU, runs on PAL or NTSC systems A manual (illustrated installation instructions) in german and english (sent by email with shipping out notice) One DIN connector 5 pin to lead out the video signals (optional for Atari 800 users) approx 50 cm shielded cable for video out approx 50 cm shielded cable for internal audio connection (optional for Atari 800 users) I offer two versions of the PCB "Standard" = Full populated (except Atari custom chips) PCB, standard HASL surface (as shown in the picture above) "Gold" = Full populated (except Atari custom chips) PCB, gold-finished (ENIG) surface (like my Sys-Check and many other solutions) The ENIG (gold-finished) surface is more rugged against rust and fouling. Because the naked PCB price doubles when choosing ENIG at this board size, I offer two versions. Prices One "Standard" PCB = 48 Euros each One "Gold" PCB = 59 Euros each Registered and insured shipping 1 or 2 piece(s) worldwide = 9 Euros Registered and insured shipping 3 or 4 pieces worldwide = 12 Euros More than 4 pieces or specialized = please ask Info: After some bad experiences with some postal services I only ship insured now. Time schedule I will collect orders and payments until the end of January, the 22.th 2017 (GMT) At the end of January I will order the parts and PCBs Assembling and shipping out can take up to 6 weeks, because there´s no holidays for me, assembling will be done in my spare time Depending on shipping time you will get your PCB(s) in March or April 2017 - This is the worst case, but I won´t promise things I can´t realize. So this is a safe suggestion. First payment, first serve: I can´t make all PCBs at one time, so small batches will be made. Date & Time of cleared payment sets the order of shipping out Please sent me a PM (personal message) or leave a post in this thread. You will get an answer soon. Practical hints for Atari 400 users The Atari 400 hasn´t any S-Video/CVBS output and no standard monitor jack, just an antenna (RF) cable. This cable is replaceable, so the best way is to remove the whole cable. You can use the hole in the case where the antenna cable was now for the new video out cable. At the end a standard DIN 5 pin connector coupling is applied. You can use ANY standard CVBS or S-Video cable made for any Atari XL or XE (or the Atari 800) to connect your Atari 400 to a monitor or television. The sound signal must be clamped from the main PCB. Nothing is destructive, only two solder drops at the mainboard of your Atari 400 must be made and one hole with ~5 mm diameter must be drilled in the metal cage for leading the video cable out. Practical hints for Atari 800 users Remark: The Atari 800 has already a quite good video output (S-Video). The CVBS output ranges something in the middle of existing video solutions. The need of my Super Color CPU card isn´t really mandatory for an Atari 800 owner, but it CAN improve video quality. Of course without any promises. I repeat that to make this point of view clear for all interests. The first option is to go ahead like the Atari 400 user. Replace the antenna cable with the new video cable. The existing monitor connector is always out of function when replacing the Atari CPU card with my Super Color CPU Card. Second option for Atari 800 users is to use the existing monitor jack with the new Chroma, Luma and CVBS signal. For this purpose the best way is to bend away the three connections from the mainboard to the power-PCB transmitting these three signals. This is reversible, non-destructive and needs only four additional drops of solder at the monitor jack. The manual will show how to do and also point at the junctions where to grab the audio signal, too. If you want, the external monitor DIN 5 pin coupling connector is already soldered. Leave your wish with your order, otherwise I will ask when confiming your payment. Any questions? Feel free to ask Jurgen

With the recent release of the 400 mini, I got back to thinking, Why can't the 400 use a Uno cart? It WILL work on a 400 with the Atari made 48k ram card and it's respected motherboard mod. The Uno can run .roms ( like Commando ) in 64k, so if it's a ram issue, can't we utilize the Uno's sram for that? I'm going to do just the 48k wire mod to a mobo ( no 48k card ), then try it out.

I like my little Atari 400 but in order to use (play games on) it, I need to get the old TV up from it's storage shelf in the basement as the 400 only has RF output. (I also have it's RAM upgraded to 1056k. ? ) While I know there is the SCCC to do this, it's sold out and it's fun to make my own board. So, I just ordered 5 of these boards and should know if it works in a little over 2 weeks. I integrated some of the electronics from the 600XLM board for video and audio. Also, I took my existing 400 CPU board and tested it out with a SALLY chip to make sure I had the theory right. The idea is that a Sally will work if /halt is held high and R/W is connected to pin 36 as opposed to pin 34. It worked. (See second pic. I stacked a couple sockets to jump the R/W and connect to the /halt pin as I don't want to solder to a Sally chip.)

Hi All, I've been working on fixing up an Atari 400 my friend gave me. It started with just getting a BSOD at boot. After attempting to clean and re-seat all the chips on the main board, CPU board, and RAM board with no luck, I picked up a 48k RAM upgrade board. After installing that, the computer booted! All keys on the keyboard worked and was able to use my BASIC cart for a while without any issues. I then I ran into another problem then where the joystick ports didn't work. (Just to note, these didn't work from the start, they didn't stop working after the computer booted for the first time) I was able to get those working by installing a new PIA chip (G65SC21P-2). Things seemed to be fine at this point. I played some games but then had issues with keyboard suddenly missing keys. Surprisingly, pulling and re-seating the PIA chip fixed this even though I was under the impression the keyboard was controlled by the POKEY and the two multiplexer chips. Anyway, long story short, I'm at the point where everything works great except the SHIFT, CTRL, and BREAK keys. These used to work as I was able to program a bit in BASIC earlier but now they're suddenly not working. I should also note, I have a 5200 that I swapped the CPU, GTIA, ANTIC, and POKEY chip back and forth into the 400 and it didn't make any difference to anything. I also swapped around the two keyboard multiplexer chips without any change. I'm wondering if anyone has any ideas or if you guys know what pins I can jump on the keyboard connector to simulate pressing "SHIFT+2" to get a double quote or something. I've been able to jump some pins to get it to display a bunch of characters but I'm not sure what combo is needed to simulate pressing SHIFT. The pinout images I've found online don't seem to match up what I'm seeing on my computer. Basically, I'm trying to rule out if somehow I borked the keyboard taking things apart 1 million times or if some other trace, chip pin, or something is broke or making a bad connection on the main board. Thanks in advance!

I obtained a local Atari 400, cassette player, and a few cartridges and tapes. My first attempt at powering on the 400 gave me no picture at all, but after doing these things: Re-capping (Console5 re-cap kit) Re-seating / de-oxit all sockets and ICs Measuring PSU outputs Swapping CPU with spare from Apple IIe (not 65C02) ...I got as far as a black screen or dark grey screen. At one point after putting back the stock 6502 I even managed to get a blue screen with cursor for a few seconds. I'd toggle the cartridge port switch a couple of times to make sure this was repeatable, until eventually the black screen wouldn't even come on unless I let the unit rest for a day. Then it goes back to the black / grey screen. I have a 2008 vintage flat panel TV that still works with analogue TV connections as well as composite and S-Video, and have tested said Apple IIe on it. Following the official Atari field service manual it tells me to check the power supply outputs, which are suspect, but then so was my cheap multimeter. I've since obtained a better multimeter. I have one of the CO17945 power bricks and I'm tempted to replace it, though its output AC voltage does look right. From what I'm reading the replacement power supplies out there are half the amperage of this stock one. I'll need to get a scope to check the clock, and I'll likely get one of the cheap ones that work with a modern PC as the display. I'll also need to order some of the smaller pieces that the flowchart says to replace. Is there anything obvious I should attempt aside from what the flowchart already suggests?

[Update - I got a 16K 400 to boot a DOS 2.5 image from my SDriveMax. So that works. I’m guessing that sdrive.atr requires more than 16K] I’m trying to test the SIO ports on several 400s. My SDriveMax works fine with my 48K 800 but does not work on multiple 16K 400s. It starts to load but then goes wonky. Can someone confirm the minimum memory requirement for SDriveMax to function? Thanks! FYI - I read that FujiNet requires a minimum of 24K of memory so that’s a no go on stock 400s

Hi, in the last months I got several reports from users of my SCCC (SuperColor CPU Card) and/or the 48/52 RAM Card for the Atari 400 when using the Atari 400 computer. The bug report was always the same: After (correctly) installing one or both of my expansions, the system starts only in one of ten (...) tries. When it boots up, everything works fine, but in most cases you got only a green (NTSC) or brown (PAL) screen. Of course I´ve searched the failure in my projects, but can´t find any. Five users returned their cards for exchange, but the exchange won´t work better - and all returned cards works flawless at my test systems. Later I got additional response about the exact same problem from users who have UAV installed (plugin version) with directly exchange (replace the 4050 chip with the UAV plugin module). So I examine this behavior more intensive and the reason was found quickly: One of the gates from the 4050 buffer chip is used for strengthen the RESET signal to the CPU and make sure it´s at a defined logic state. So if you removed the 4050 for the installation of an UAV (or the SuperColor CPU Card, even when this is not needed), then the RESET pin 40 at the CPU is floating around and you have an undefined condition. Some CPUs doesn´t care about this and start always even when the RESET input floats around 1.7 volts (for example), others didn´t start up (SYNC = constantly low). However, if you´re using the SuperColor CPU Card and the 4050 is missing: Just plug it in again and the faults should be gone. If you´ve installed the UAV plugin module, then a fix is needed. The TBA manual suggest to solder the UAV plugin module "piggy-packed" onto the 4050, which is one solution. Another solution is to solder the 4050 chip (partly) "down-under". This is useful when you change the hardware some times (like I do in my tests). For permanent usage it´s simpler to install the whole chip OR use the piggy-pack way ? Look for this chip. First bend all pins in the horizontal position. Cut off all pins except pin 1,8,14 and 15 as shown in the picture above. Carefully bend all four pins upright like shown above. Shorten the pins at the half. And solder the chip from the solder side of the Atari 400 mainboard upside-down to the socket pins of the 4050´s place. See here pin 1 (right) and pin 8 (left). And a view from the other side - pin 15 the left, pin 14 to the right next to pin 15. Doing this mod will fit without problems in the metal cage.

Hi, some weeks ago another ABBUC member ask me for a way to update his Atari 400 to 48K main memory. Until the end of 2016 mostly I prefer the usage of the genuine Atari 400 48K Factory Upgrade Kit - Atari part number CO61553. BEST Electronics offer them until somewhere up to the end of 2015 for approx. 25 USD each w/o any additional parts or manual. In 2016 the price rises up over 35 USD and now it´s sold out. Due to this impossible mission to get more of the CO61553, I create my own solution - even better than the original Here´s the Atari 400 48/52 KB RAM-Card with "external" OS-ROM support using standard EPROM sizes: This card is a full replacement for the 16 KB built-in RAM card. At least only two wires must be soldered at the bottom side of the Atari 400 mainboard. My RAM-card uses the same pinout like the CO61553 by Atari, but only 2 of the 4 wires suggested by Atari are really needed. But it works also, if you have already equipped an Atari 400 wit the CO61553, you can easily change to my RAM card, if you want. The 74LS243 chip has to be removed, it´s not needed any longer. After soldering the 2 (or 4) wires, just plug in the DIL connector into the socket were the 74LS243 was before, the other end has to plugged on the new RAM card. That´s all. The new RAM card uses SRAMs instead of DRAM and provides 48 KByte or 52 KByte main memory. When enabling the 52K RAM mode, the address range of $C000-$CFFF is also RAM. Please remind, that this area isn´t usable under BASIC (or, to be more precise, I didn´t know about that). A jumperfield on the PCB let´s you choose which size is active. The second new feature is the possibility of using a standard 27128 or 27256 EPROM for the operating system (and math-pack). When the "external" OS-ROM mode is enabled, the three ROMs on the Atari 400 mainboard won´t be used anymore. You can remove them or leave it in their sockets. The EPROM´s first 6 KB are unused, then 2 KB math-pack will be followed by the 8 KB OS-ROM code. A third jumperfield switches the highest address line A14 of the EPROM, so you can hold two different operating-system sets in one 27256 EPROM. What you get? - PCB "Atari 400 48K/52K RAM Card" with ENIG (Gold contacts) surface levelling. Picture shows only standard HASL, but I offer only the better quality with ENIG. - Ready-for-use crimped ribbon cable for the 74LS243 socket to connect with the RAM card - some wire for the 2 or 4 solder connections at the Atari 400 mainboard´s bottom - Installation instructions with pictures in english, sent by email Price? - from 20 up to 25 euros each depending on the amount of orders - Shipping costs to any place in the world for up to 5 pieces is 9 euros Schedule? - Please show your interest and how many you want to order here in this thread - I will collect inquires until 2017 July 2nd (end of date) - If 10 or more orders will be placed, everyone who´s interested get the payment details - Shipping out at the end of July 2017 Best regards, Jurgen

Hello. I recently obtained an Atari 400 labelled as "working". Upon setting everything up, it will only display a green screen. Every time I turn it on, it only displays a green screen. Where should I go from here? What are the most likely causes that I should investigate? Some more info I forgot to include: 1. A green screen is displayed 100% of the time so far. Never a black screen / anything else like some other posts I have seen. 2. I have tried inserting various cartridges, however something is wrong as carts do not click in all the way on this machine (tested and work fine on my other 400). So, I am not sure how to test other functions of the machine using carts until I can figure out this problem. 3. I have used the power supply with another Atari 400 which works fine.

Ok guys, I’m stuck. I’m only 16 so I don’t reeeeeeeally know what I’m doing, but I need your help! Atariage, I’ve been scammed!! DUN DUN DUUUUUUUUN!! I bought a “working” atari 400 off of OfferUp whose only problem was that it had a cut video cable (Which I replaced with one I pulled from a broken 2600) and no PSU (which I had bought before the system arrived). I, being the idiot I am, DIDN’T test the system before starting my cleaning/retrobrite process (pictures below ;) ). After that week of school I threw the system back together aaaaaaaand... black screen... :( I’ve tried Everything I can think of, I reseated all the chips on the whole computer (cleaning the pins and the sockets as I did), cleaned the the ram and cpu board connectors, started it up with a star raiders cartridge, made sure everything was grounded properly, deoxidized the power jack, cleaned the channel selector, tried multiple tv’s (both new and old), and STILL I get that black screen... WHAT SHOULD I DO?! Any help would be greatly appreciated!

There is a small hole in the rear of the case other than that it is perfect. The mem upgrade makes it a new machine. Comes with power supply. $100 obo. Thanks, 400_mem.mp4

Atari 400 with power supply, works great 50$ Plus shipping (OBO). 20201216_171901.mp4

Hi everyone. I sold this Atari 400 with 410 recorder on eBay with no only a power cable, no plug attached. The buyer purchased an additionally required cable to hook up to a screen and when he turned on this appears on the screen. The eBayer 100% knows what they are doing and said if I partially refund then he will get it fixed. He only paid £50 for it. Is this a case of cleaning the inside with some alcohol and putting it back together? System hasn’t been used in...25 years. Many thanks for your help.

======================== EDIT: These items are no longer available. ======================== I recently came into possession of a decent sized collection of Atari gear. I grew up playing games and computing on similar Atari hardware so I'm somewhat familiar with the gear. Despite most of the gear being in excellent condition, it was destined for a trip to the electronics recycler. Recognizing the historical significance of the gear, I snatched it up to ensure that it can live on. I'm looking to sell and redistribute the gear to the community of enthusiasts here to ensure that it can be preserved and enjoyed for many more years. I spent many hours cataloging, testing hardware, photographing everything, and uploading photos. I've done my best to test and verify the functionality of most of the gear in this listing. You can see a list of everything that I have here: https://bit.ly/2qeRtAA Each item includes link to an imgur.com posting with photos. Most items also include a note about the condition of the item. Sorry, it's not the most convenient way to view everything in one shot but it works for me. I didn't include prices on my spreadsheet as I don't really have the time to determine the value of each item. In many ways, the value is really determined by the community here anyway. I would simply ask, if you would like to make an offer for anything on the list, make it a reasonable offer. Also, keep in mind there are shipping costs. Some of the larger items may incur significant shipping costs. I can certainly offer local pickup for anyone in my area. I'm located in south central Pennsylvania (York, PA area). https://goo.gl/maps/bWMy8WTxebmbAu54A Contact me via email or PM if you're interested.

Is it considered easy or difficult to reprogram games for the Atari 400 or 800 as to run with professional quality on a 5200 system? Are there big differences in 1) hardware 2) program language? I’m very ‘layman’ as to programming and hardware. If its possible, please, describe or explain in quite straightforward or common terminology.

Hello all, hoping someone here can give me a bit of advice regarding SD card/compact flash cartridge solutions for an Atari 400 - after years (ok, decades) of wanting to play Lucasarts and Llamasoft games on an Atari 8-bit I finally got hold of an Atari 400. Only to find the membrane keyboard had started to die so I couldn't hold down Start when turning on to load from tape. Got that replaced with a new one from Best Electronics (and in the process also discovered it had had a memory upgrade so it's a bit more capable than a stock one) but still having a fair bit of trouble as need to replace the belts in my xc12 and a spring in my 410p. Just about able to get *some* things loaded on the 410 but it's very hit and miss so think what I could really do with is a cartridge solution to load from disk/tape/cartridge images instead. So, what would you recommend for an Atari 400 (with memory upgrade)? I know the atarimax myide2 isn't an option as borrowed one from a friend, only to find it's XL/XE only. I've seen sd2sio and sdrivemax doohickeys going on eBay but would really rather a cartridge solution instead, does such a thing exist or are they all only for XL/XE systems?

I'm looking for assistance in repairing an Atari 400. It has an intermittent issue with graphics. Sometimes it starts up fine and everything looks normal. When this happens the graphics and colors are fine until the computer is powered off. Other times the colors are off on startup, for instance sometimes when playing Donkey Kong from a cartridge the graphics on the title screen are green. Other times it starts with a white background. The only way to resolve this is to power cycle. Other times sprites are missing. For instance when playing Pac-Man from a cartridge Pac-Man and the ghosts are missing. You can still control the invisible Pac-Man by following the dots as they disappear. You will never die from hitting a ghost. Sometimes when playing Donkey Kong the Jumpman character is missing and just a solid vertical line runs down the screen at the position he should be in. Again only power cycling will resolve these issues. Any ideas what can cause this? Could it be the ANTIC? Any help would be appreciated. Nick

So I am working on a Atari 400 I picked up at a rummage sale (I am new to classic Atari systems) Blank screen so I do a little research and pop it open and find this board inside. It is connected to a SPDT switch that needed to be replaced. I got the 400 working but have no clue what this is or what the switch does. Any help is greatly appreciated.

I'm working on getting Atari 8-Bit set up in RetroPie using the Atari800 emulator and most everything seems to be working just fine except for this: My WASD keys don't deliver any input at all. I've tried multiple keyboards, checked to make sure they aren't currently bound to joystick controls in the emulator and I assume there is somewhere in the emulator which is binding them to "movement" but I can't seem to find it. So right now, any game that requires pressing "S" to start, like the Scott Adams adventure games, I can't do anything with because my "S" key doesn't work. I've scoured Google looking for solution but it seems there aren't many people who have set up Atari800 on the RetroPie because it most certainly isn't the most user friendly of emulators. Anyone else run into this same issue and found a solution? Thank you in advance for your help!

The Adventures of Bounty Bob, brave Cananian Mountie on the trail of Yukon Yohan. Bounty Bob, who looks neither like a Mountie, nor like the miner on the box covers and as the title would suggest. Until now. With sprite designs by TIX, and sprite hacks by your's truly, I introduce to you the burley Miner 2049er! Click here to download Prior revisions and the thread on how this was hacked here

Picked up an Atari 400 and 130xe with loads of software this week. Tried getting it working allong with an 810 disk drive. However the coaxial cable is damaged so thinking about doing an a/v mod on it.

Being a relatively new Atari 400 owner I've been hunting around for lots of Atari 8-bit computer game cartridges lately, and today I got a couple games in the mail that surprised me in that they simply would not fit in the Atari 400's cartridge port. The cartridge shells are too wide to make it more than halfway down the cartridge port and they snag up on the metal shielding rather quickly. Has anyone else experienced problems like this, and are there any other games known to not fit in the Atari 400's cartridge port? Specifically I'm wondering whether or not there are issues with any of the Parker Bros. and Activision carts, since those are the main third party games I'd like to play.

Hey there lovely people. I just got my first classic computer in the mail today, an Atari 400, and it worked great for about 2 hours. However a problem soon arose that I could use some advice on. The problem is that the all of a sudden the computer thinks the + key is being held down, so when I load Atari BASIC or just boot into the built in notepad application with no cartridge inserted all I get is a continual stream of + symbols and can't enter any other inputs. The strange thing is that if I power the computer off and leave it alone for 10 minutes or so then come back and power it on everything works as normal again about half the time, including the + key. I can press the + key all I want and can't make it stick again, but after a few minutes of use it will go back to thinking the + key is held down even if I don't touch the keyboard at all. So what I'm trying to figure out is whether the keyboard needs to be replaced (which would be quite unfortunate since I blew all my discretionary funds for the month on the computer itself and wouldn't be able to afford to replace the keyboard until at least next month) or whether this could be an issue with another piece of hardware in the computer. I've read that the POKEY chip is responsible for interpreting all the keyboard inputs in the Atari 400, so is it possible that a failing POKEY chip might create an issue like the computer thinking a key is being held down when it isn't? Any advice on this matter would be greatly appreciated.

I recently purchased an Atari 400 computer, a handful of games for it, and a book on learning Atari BASIC. Now as I begin learning BASIC I could really use a way to save my programs and play disk based software, so I'm in the market for a 1050 disk drive that is in good cosmetic condition and proper working order with the power supply included. I'm looking to spend around $85 shipped on the disk drive and it doesn't need to have any custom modifications like Happy or anything like that, a plain old standard slow speed drive will do just fine for my needs. I'd also be interested in purchasing a 48K memory upgrade for my Atari 400 at some point, though acquiring a 1050 disk drive and some blank 5.25" floppy disks to use with it is my first priority. Thanks for taking the time to view my ad and if you happen to have a working 1050 disk drive in nice condition that you'd like to sell then feel free to shoot me a PM about it!