Holding the Option key at boot is not "compatibility mode" it disables the build-in Basic ROM that is in the XE and XL line. :)

Hey, just wanted to thank you for this video. I had nearly the exact same issue as you (too-hot heat sink, no power to the drive) and was getting ready to give up, but I saw your video and found my TP110 (Q6) was shorted to the heat sink very much like yours (28:28). In my case there was an insulator between the TP110 and the heat sink, but there was NO insulator on the screw. I used a bit of molding plastic to create a new insulator and my flea market 1050 find is now working perfectly. So, thanks!

Nice 1050 video!!..Finally..somebody that goes into detail of a 1050 repair!!

Minor note: holding option while booting the 800XL doesn't invoke compatibility mode, rather it disables BASIC; this is akin to booting on an A800 without the BASIC cartridge installed. In order to make the 800XL compatible with older software that only runs on an A800, one needs to boot with a "Translator" disk.

This was a lot of fun, and good motivation for me to figure out what's wrong with my own two 1050 drives that I finally got back this weekend after my brother-in-law had taken all my Atari stuff after I moved to California thirty years ago. Thirty years in my sister's basement was not the best environment for all this stuff, but a lot of it still mostly works. My trusty Atari 800, while it seems to work well, the keyboard doesn't work at all. I think I know what I need to do to fix that. The 1200XL that I bought used back un the day, works, even the keyboard (I found I even have a spare) but the character set is garbled. "R" shows as a "Z", space shows as an open parenthesis, and I can't make out any other correlations. This one has me completely stumped for now. My Atari 400 that I bought used for $19 back then works just as well as it did when I got it. The cassette interface never worked. Everyone complains about the keyboard on the 400, but it's bulletproof and it still works just fine. It's Not THAT bad. But if I want to save any work I do on it I'll need a disk drive. My trusty old 1050 that I first got for my 800, I had modified with a bootleg EPROM of the Happy Drive upgrade that offers turbo speed I/O and true double density. It now starts to power up and jostles the drive mechanism for an instant, but then seems to lose connection with the power supply. I put Deoxit on the power port and the power supply plug and when I turned it on, the unit came on and the drive activated, but it didn't stop until I turned it off again. After that it was back to its old "reluctant to start" behavior. I bought a second drive, shortly before I moved, that I probably used for only a couple of weeks and repacked in its original packaging when I left. So I consider it to be basically "new-in-box." It's behaving exactly like that second drive you spent so much time on. The unit powers on just fine, but there's utterly no response from the actual drive itself. At least I know I haven't had the kind of work done on it that your unit has had. You've given me ideas of what to look at.

I bought about 15 arcade games from Showbiz pizza 25+ years ago and sold them all to one guy after fixing them all. About 5 years later a friend of mine asked me to go with him to pick some arcades he bought. When We arrived, I quickly identified them as the ones I sold 5 years Previous. Half of the games no longer worked. A few needed new power supplies installed. There were a few games that did not work at all. After investigating the PCB's, We noticed that all the roms in the non-working games were switched into the other games! I guess they thought, well, if it fits, it must work! NOT!. We eventually got those games working again by replacing the original power supplies with switchers. Some people should NOT touch Electronics.

On a serious note, the 6507 is a reduced pin count/reduced cost 6502. With a suitable adapter board you could use a 6502 in its place.

My 1050 was had a lot of read/write errors when I got it, but very soon after a tantalum capacitor on the board blew up. After I cut off the remnants of the cap, the drive started working perfectly!

Holding Option while booting doesn't switch to a compatibility mode, but switches off the built in Basic. On an Atari 800 with inserted Basic Cartridge you would also have to hold Option to boot games.

I'm really enjoying your videos! Very accessible, even for an electronics beginner like me. Keep them coming!

Great Vid. This previous "repair" job is a real car crash. Keep up the great content Arty

Hi Art, I am glad you were able to find a 6507 chip in your own stash. I was able to find several online for about $10, which surprised me a little. Great video as usual, I can only give it one thumbs up for a two thumbs up job!

Great video - that chip's identity was priceless!

You should be nominated for the Nobel Prize for Patience.

Wish I found you forever ago!!! My 1050 needs help! Just getting boot error....🤷‍♂️

6:30 It is not compatibility mode but to BOOT without BASIC ROM (Cartridge A installed $A000-$BFFF, Cartridge B right slot $8000-$9FFF) loaded to the 8K ROM bank of memory (or 16K max $8000-$BFFF, unless bank selected later 32K-64K cartridge ROM disk conversions from XE & XEGS systems). 400/800 require removal of BASIC cartridge to fit any cartridge game written in machine code language for speed. Very few software packages used BASIC but machine code language for speed. There was a conversion disk (The Translator) that would turn off the on-board 10K XL/XE OS-ROM and load the old 800 10K OS-ROM into RAM (Real 400/800 compatibility mode) which require a 64K machine. All software that did illegal OS calls making 1200XL, XL/XE machines incompatible without 'The Translator' disk. All high memory contained hardware register chips or OS ROM starting with 4K unused($C000-$CFFF), GTIA($D000-$D0FF), POKEY($D200-$D2FF), PIA($D300-$D3FF), ANTIC($D400-$D5FF), OS($D800-$FFFF), includes unused 3 pages ($D100-$D1FF, $D600-$D7FF). 130XE four RAM banks($4000-$7FFF) swapped in from spare 64K. 16K $0000-$3FFF, 400 & 600XL basic systems 32K $4000-$7FFF, 130XE Bank Switch RAM area, upgraded 800 48K $8000-$BFFF, 800 maxed out, 16K cartridge ROM game or high 8K ROM game 64K $C000-$FFFF, 4K unused, 2K hardware register chips & 10K OS ROM, 4.75K of dead address space free RAM after DOS ($3307-$7FFF), page 6 routines + 8K Right Slot = 27896 ($3307-$9FFF)

Super cool vid, thanks for sharing.

For such issues You can always try to power a DUT from a bench regulated power supply. You should automatically see from the start that it draws too much current from the start :)

Thanks for the memories!

Amazed that you still could find that IC . . .

Very informative video sir

Nice detective work!

Great repair - so many things hacked on that poor thing! The 6507 seems to be fairly easy to obtain through eBay - about $5-7 each, assuming it doesn't need the genuine Atari branded part? Worth doing so you can piggy back and do disk-to-disk copying etc. I so wish I could get my old 800XL setup back - since moving from UK to Australia, they simply don't exist here. BTW, that Option press thing is to disable on-board basic, was needed more often than not to boot most software :-)

*THANK!!!...SALUDOS DESDE EL SUR DEL MUNDO....CHILE-ATARIANOS FOR EVER*

Ah, the joy of repairing after a botched repair

I thought the regulator mica insulator missing was bad enough - and then you found a completely random chip replacement - that takes the prize easily I think. I'd forgotten the amount of noise a large floppy drive makes too - you know when it's working :o)

Great repair! I often fix these drives. Do you have the calibration software? It enables you to adjust speed, calibrate sensor and runs multiple tests. It's like a 1050 mot! Very enjoyable video.

Flipping the motor power connector with a working power device would have burnt out the feedback coil of the drive motor, which is not repairable. Just like the Fujitsu drive is, got the click of death on it.

Arty, are you still repairing 1050 drives? I have two units that can read disks but can't format.

Crazy!!! I have several of these and they all have those "ugly marks" on them!!! Dont know what caused them. Each drive came from sources not connected to each other.

Thanks

I have a 1050 powers up...but the drive does not seek. I would like to send to you to have it fixed? Do you do this type of thing.

Ohh I had one of these for my Atari 800... I think it was...

Arty always has a proper "McGuffin" for his repair videos. The "McGuffin" was best described by Alfred Hitchcock as the thing that drives the plot but which the audience won't be interested in.

If you know how to piggyback RAM chips for the 1050 and have the right EPROM and binary to burn on them, you can hack and upgrade 1050 drives into true high speed double density as used by SpartaDOS. The upgrade is the US Doubler made by ICD. Though I imagine some people will mention the Happy board. Holding down Option disables internal Atari BASIC.

So I just purchased a lot off of ebay and the 1050 doesnt work. Same characteristics of your second drive. The power light comes on but the drive busy light does not. I disassembled it but couldnt see anything obvious. I'm no electrical engineer. There seemed to be no repairs done on the drive. I'm wondering if the processor is bad and would like to know where I could source one. Thanks!

Somenone kept that 6507 for his personal stash of ICs.

I am trying to get a drive to work for me. When I power it on, both lights come on, the spindle spins and the head goes in and out. Then one led turns off as expected. However when I turn on my Atari 800, the drive just sits there. I have replaced the SIO cable and have tried the same thing with my Atari 400. I made a short video, so that you might be able to see what is going on, and what I might try to fix this issue. @t

So the chip was not OKI-dokey? (Sorry, had to...)

A 6507 wouldn't be a problem.

I realise this was over a year ago and I don't know what you have done with the drives since making the video but if you were to install the 1050 'Happy' Drive enhancement board, it would replace both the 6507 chip and the Tandon BIOS chip and give the drive better functionality and true double density (180k) disk space use. See here: kzfaq.info/get/bejne/mpNgaNCWudbQlKc.html Happy is available from: www.atarimax.com/

A nice thermal camera would have helped alot right??? they are expensive tho

Mine has to sit turned on for 30 mins then it works like a champ all day, wtf? 🤔 🧐 🤨

I am trying to get a drive to work for me. When I power it on, both lights come on, the spindle spins and the head goes in and out. Then one led turns off as expected. However when I turn on my Atari 800, the drive just sits there. I have replaced the SIO cable and have tried the same thing with my Atari 400. I made a short video, so that you might be able to see what is going on, and what I might try to fix this issue. @t