xrbrevin

if you have an 800 top cover i would be very grateful 🙂

^^ that it be

further to what _the doctor__ mentioned: certain carts bypass the normal system procedures/hardware and thus can help diagnose a fault. they are built to operate differently to the normal carts and have their own classification term but i cant remember it. maybe 'diagnostic cart' but i cant be sure. the only one i know of is star raiders as recommended above but there are others. maybe other people can advise?

at that price it is ironic that the seller lives in 'Dorking' (groan..)

if i remember rightly, it involves 'jiggling' 1. remove the 2x screws and if necessary also the 2x parallel port shield screws 2. lift the front-left side of the motherboard 3. pull it towards you to disengage the power switch from its aperture - you may need to flick the switch to help it clear the case 4. disengage the SIO port from its aperture. start by clearing the top-left side of the port - you will likely need to jiggle the case near the port to get it started 5. disengage the joystick ports from their aperture for reassembly, reverse the above. be careful to avoid getting the motherboard stuck at the rear-right screw hole as there is a small lip that likes to snag and hamper the progress

BASIC can be upgraded/replaced with an EPROM - look on the forum for guidance & further info

it may be worth reflowing the solder on the chip sockets in case the disturbance has upset a weak contact

great fun! i particularly like the tie-fighter look-a-likes, no self-respecting 8-bit space-shooter game should be without them 😁

Hang on to yourself! 😛

my daily driver is an Alps variant and they are one of the better ones. altho i had to make mine socketed - it was quite a task! i went for the antonia RAM & OS upgrade which is also great but my 1200XL got the U1MB. in the image of yours, it looks like there is no RF shielding. theyre not essential but it may indicate someone has been 'meddling' in there in the past... its also nice to see it doesnt have the infamous MT brand RAM

its pretty consistent with current prices but the main thing is that it is in very good condition and fully socketed ones are not that common - i'd say its a keeper 🙂

quite a clean example really, did you give much dough for it?

can you post a pic of the mod?

can you test on another screen?

some more pics of my mod i did add the tantalum cap for what its worth but it didnt seem to make a noticeable difference

nice one, i can highly recommend it. its as good as my 800 on s-video

i believe @Mclaneinc is considering selling a computer

for all we know, he could be an electrical engineer..!

welcomes! if no-one has been inside butchering things, the most common causes of blank screen include bad RAM, OS ROM or MMU RAM chips can be bought, OS ROM and MMU can be burnt using an EPROM programmer. display cables can be home-made and for power, the 800XL uses 5v 1a so many people use a USB source - there is a thread on here that goes into further detail

why not try the marketplace here on atariage? theres a higher chance of scrupulous clientele and you can portray your items as well cared for as you are a genuine enthusiast

i read somewhere that the 400 struggles to operate a disk drive due to 16k RAM. the recommendation is to increase the RAM to 48k for reliable disk usage. i assume the disk drive functions need to occupy some RAM in order to work. the SDriveMAX emulates a disk drive so this may be the cause of your issue. the way to test is to try several 8k games and if they all work and the 16k ones are hit 'n miss then its likely youre reaching the RAM limit. i have a 400 with the 48k/52k upgrade board by @tf_hh and it works just like an 800 🙂 - highly recommended!

this is a great site: http://www.mushca.com/f/atari/index.php?idx=0 all uploads are tested and working. it also gets updated regularly with new games 🙂 well worth bookmarking

many large carts work on the 16k machines. the cart memory is mapped to an upper area of what the CPU addresses - above that of the 16k system RAM. the CPU is none the wiser i tried a bughunt cart on my 400 and it worked fine. i was puzzled for a wee while until i found out how it actually functions

always a pleasure visiting your site!

does this help?