xrbrevin

here are 3x more i just knocked up @Mr Robot you are welcome to add them to your site if suitable?

altho i cant recommend anything specifically as you are in a 120V country, over here amazon sells PSUs for guitar effects pedals that have the correct output for the AC Atari hardware. Maybe you could find something suitable on your local amazon? just found this:

in the 1050 version of sams computerfacts there is info to do a resistance test on the stepper motor windings Atari_1050_Disk_Drive_Sams_Computerfacts_Technical_Service.pdfAtari_1050_Disk_Drive_Sams_Computerfacts_Technical_Service.pdf the diagram is on page 17 of the attached

shame its in the "oh crikey" price bracket..! 😮

it be inside the AC power supply

is the drive stock or does it have any mods fitted? i find that to pass the 1050 diagnostics, the drive has to be stock did you set the zero sensor?

nice - very much like the berzerk speech! you even used the same 80s cheesy speaker shown in the article 😎

Thanks to all for the input, DrVenkman called it - the PIA! (Pesky Infantile Article? hehe) Heres how it went: Desoldered the CPU, supplanted but no change Multimeter'd all caps, resistors and transistors - nothing untoward found Found a spare 74LS08 - piggybacked it on but no change Desoldered PIA - replaced and it booted to missile command (no keyboard so this is correct), reset - into self-test. rebooted with keyboard - got basic, all carts work, SIO works! I have had a PIA casualty before, but luckily they are a universal off the shelf part. Great success! The machine is now playing demos from the Side2 cart 😎 Now i have to tackle the keyboard internal dupont connector botches. Hopefully it will bring the faulty keys back.

when powered on, check the 8x RAM chips for excessive heat. if the are 'MT' brand they are known to have a high failure rate. you can piggyback new RAM chips on top of the existing ones to help diagnose which one(s) has failed - be sure to align all the pins and the notch at the end

i think its more a case of garbage signals. i can boot to missile command if i hold down select, it doesnt if i dont. here is a pic of the shoestring ROM result, it appears this way immediately. i dont think it supports the XEGS directly as the silkscreen 'U' numbers are wrong but it does support the 2x DRAM chip 65XE (4464) which the XEGS also uses. I get same results with a homebrew GAL MMU and same results with a change of DRAMs. time to desolder the CPU..

800000

ok, thats another 40pins of xe-spec desoldering. stronger coffee required..! Sadly, the Shoestring ROM just made a high pitched tone.

My L34-41 is populated with beige components but i like the idea of trying the mod. i have ordered some 1nf SMD caps so while i wait i will swap out the CPU

thanks for the replies. alas, no joy. i dont even get the fart noise and not seen basic thus far. With no (diag-spec) cart i just get a black screen. SIO devices do not respond. yes, this is an odd thing - with keyboard attached it will boot to missile command. if i start a game the cursor just goes to top-left regardless of whether a joystick is connected (pokey issue?). there is a low-tech historic repair on the keyboard cable that i have not tidied up yet tho. The first boot up went straight to memory self test. it got past half way with no errors and then reset itself to a black screen. Ive never managed to get back into memory test since. The SALT cart shows RAM: 40k, TIA: PAL, ROM: ERR, NTSB: ERR. The 40k tested fine. SuperSALT flashes up a brief orangey-brown screen with SYSTEM ERROR F4. Sometimes it will emit a high pitched tone. I have swapped out thus far: OS ROM, MMU, Freddie, 2x DRAMs. Im wondering if there is an addressing issue with the CPU but its not socketed. (pesky XE desoldering..!) I'll get that Shoestring ROM burnt and see what it does. Many thanks for the link! Just gotta wait for the UV eraser to work its magic.

I just obtained an XEGS which will only boot diagnostic carts. Ive burned a new OS ROM but the fault remains. Does anyone know of an OS Rom image that boots straight to a memory test? I cannot use my Sys-Check device due to it being an XEGS..! Cheers!

see if any of the ram chips get hot if you have any loose compatible ram chips you can piggyback them on to the fitted chips locate a culprit

thanks! the bezel is a warm yellow, not green - its a shortcoming of my canon camera. it wont use flash while the GG is powered up so heres another attempt

hmmm, (cheap digital camera) case is mid to dark brown and the bezel is yolk yellow

i know some of us have other 'underling' consoles so i thought i'd post an image of my newly re-cased sega game gear i chose the colours based on my appreciation for the '70s styling of the 400 - hope you like it!

alas, not me - my deskspace is ever-shrinking and the blackbox demands too much turf! i agree, it has been superseded in recent years by other devices so i think the demand is a more narrow market. interesting to see and discuss tho

does £150 quid represent good value? i wonder if the price is discouraging the bids or will there be a last-second blitz?... 🤔

i got one of these and it works fine: https://www.amazon.co.uk/gp/product/B00F5VULA8/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

heres one on UK ebay: https://www.ebay.co.uk/itm/Atari-Sio-Cable-Nm-Ratro-Gaming-Vintage/383837877867?hash=item595e85366b:g:r44AAOSwRkVfxr2C

or obtain 3d printed ones?

the original cart has a glob-top chip in it 🤔