xrbrevin

Atari 800 in Chocky episode 1 at 18m 49s

XEGS can be modded to 128k quite easily

was it just another attempt to use up their inventory of chips? at the time, i thought it was strange because 16 bit computers had been available for a year or two

belt failure?

when working correctly, on power up the head moves forward and back. this tests the track zero sensor. if the sensor has failed, the head only moves forward. do you have the means to run the 1050 diagnostic? you will need another device to load in the atr file, then power up the drive as drive 0 with a dos compatible disk in it and you can perform the tests. 1050 Disk Diagnostics.atr

the slow boot means the computer is polling the drive ok does the drive 'zero' itself ok on power-up? sounds like the drive head needs cleaning with isopropyl alcohol, its the easiest thing to try first

if the cart still works its likely to be a blob of gloy thats come unstuck

user flashjazzcat does atari 8bit repairs in the uk

just snapped up an old favourite:

video game authority?! video game ar**holes more like

an intriguing bit of A8 history. i note that the ICs have been de-labeled... heres a pic for the archives

this just turned up on ebay - anyone know what it does? https://www.ebay.co.uk/itm/Atari-MAGICAL-ELECTRONICS-cartridge-for-6502-8bit-machines-PURPOSE-UNKNOWN/402249001776?hash=item5da7e8ab30:g:bmAAAOSwfxReqwNf

huzzah! nice work did you know you can get a cheap self-assembly oscilloscope kit on ebay? they are under £10 quid, maybe a little bit more if you want an acrylic case. plus theyre fun to build! 🙂

see this topic:

ah i see, very useful to know 🙂

they are the components bolted to the metal plate - the rearmost 2. the left pin is input voltage, the middle is ground and the right pin is output voltage. take care not to contact 2 pins at once as it will spark and risk damage. for this reason it might be easier to test via the underside.

its rare for any caps to need replacing

its a shame the game didnt include buck rogers disco dancing:

nice batch of items! altho 2 of them ought to be returned to Juli Wade! 😛

apologies, i shoudve been more specific - im thinking for OS, MMU and RAM for OS and MMU you can use an EPROM burner and replace them for less cost/easier availability. for RAM you can either substitute or piggyback. someone recently asked if the atari will still power up with some RAM chips removed, it would be interesting to find out. i reckon itll need at least 16k which is 2x chips. the uppermost chip is the primary one - in some machines with cheapo 'MT' brand you often find it has a high quality branded one in this socket and the other 7 are MT. this was done at the factory to reduce costs. this primary chip has an additional purpose but i dont know the ins-and-outs of it myself. if youre up for it, remove the bottom 6 and you can use them to piggyback the upper 2. it will only cost you time and may help you diagnose the pesky gremlin 🙂

do you have access to another atari to try a chip swap process?

press 'S' to allow your ears to recover!

in case you havent seen them already, there are 3x MULE cart labels here: https://atari8bit.net/homebrew-cart-labels/

have you searched the forum? i did a quick search and found the following: unfortunately there are no pics and some of the links are expired but you can try pasting them into the waybackmachine: web.archive.org maybe itll turn something up? theres a pic in this thread tho:

Vote for #5 but i like the metallic addition in #3