DavidMil

Because I couldn't find a parts list from Atari and no silkscreen on the board, I used the silkscreen in the Field service manual and the parts on the modem itself to make a list of the parts in the 835. Below is the attached list of parts in PDF format. A few have Atari part numbers, but most don't. David 835 Parts List.pdf

Not talking about anything to do with the power supply. BillC is correct in that this is an isolation transformer. It separate's the modem from phone line. I guess what I'm asking is for any sources to find replacements. Neither Best or My Atari has any. Sorry for the misunderstanding, David

Does anyone have any information about the transformer (T1) in the 835 Modem? The parts list in the 835 Field Service manual is a joke. It only lists 18 parts (no Caps, Resistors or transistors) including the phone cord and the Telelink II Cartridge. All the info listed for the Transformer is a part number: FC100283, and a description: Transformer, 600 ohm. I've ohmed out both of my 835's and both read about 180 ohms on the phone side and 75 ohms on the modem side. Both of the transformers have these numbers stamped into the metal on top of the transformers: 94-100-049 549-8340G If anyone can shed some light on this part I would be VERY grateful. Thank you, David

No, it looks like they just scanned the Atari version into a PDF without fixing any errors. David

One thing I've always been is a collector of documentation. Some is reprinted from Atari Mania, and some has been purchased from Best over the years. I actually have an original version of the 1200XL Field Service Manual. I've got the PDF version too. To be honest, I didn't think about looking at the PDF version to see if any of the errors had be fixed. I'll take a look at that tonight. I'll let you know what I find! Thanks, David

I'm sorry, I also didn't realize I was still on the fist page. Well done! David PS I love mouser too! DM

I agree with DrVenkman. I'd look at the sockets real hard. Atari was known for putting cheap sockets in their computers. I have on occasion even pulled socket pieces up still attached to the IC pins when removing IC's. I think I posted some pictures of that about 3 or four years ago. Plug the chips in and test for continuity between the top of the pins coming out of the IC's and the under side of the motherboard. I would stand the board on edge and wedge it up with a couple of heavy books to do this testing. David

I wanted to add a couple of pictures of the Hi tek plungers that I did a 3D print of. Like I said, they work beautifully in the keyboard, but the inside is to tight for the keycaps to fit in. David

I've run into a wall with this project, but I haven't given up yet. The company that did the original scans for me is no longer in business. And the first samples they sent me work fine in the keyboards, but the inside opening is too small for the key caps to fit in. I sent the CAD files to another company, but they said that the files are locked and cannot be modified. I checked around and the cheapest that anyone else would rescan the parts was over 500 dollars each! So I've been looking at buying a 3D scanner that can scan parts that small, but the cheapest one I can find is over $1500. I even bought a Prusa i3 MK3+ 3D printer for my Christmas Present. I tried to modify the 3D print file created from the CAD file but that was a disaster. David

Well right off the bat BillC caused me to find an error in my schematics... Q2 and Q4 should be 2N3906's and not 04's. Very nice blowup buy the way, BillC! Things in the schematics that I could not figure out I left as is, and I have no way to check on the larger ROM chips. I had to blow up the drawing 511% but I finally figured out all the notes and the table on the left of Page 1. This revision to the schematics was done with Windows 10 and Paint 3D. I moved the traces around between the two pages to get them all aligned. I printed them out on my HP OfficeJet Pro 8600 and on my old LJ 4000 and they lined up very well. Also did a PDF version but they were slightly off. Please continue to let me know about other mistakes. Some of my work kept me up after 3 AM, when I started seeing double! I'd hold off a while on adding them to you Library Mathy (nice to hear from you again). Here is the corrected page 1. David

Thank you both for the kind words. Just being back and reading through all the new posts makes me want to get involved again! As promised here are the cleaned up 1200XL schematics, and the revised Imperium Galactum star map. The three worst problems I found in the 1200XL schematics where: 1. The Electrolytic Cap C155 goes to pin 8 on the SIO connector. Not pin 10 as the old schematics show. 2. The original schematics shows that the collectors of both Q17 and Q18 are tied together. On my 1200XL (Rev 13A) the Emitter of Q17 is tied to the collector of Q18. 3. The Collector of Q4 does not tie to the Emitter of Q2 as shown in the original schematics. The Emitters of both Q2 and Q4 are tied together. I don't know if these changes were done in a revision or if it's an error on the schematics, but I've ohmed them out to verify the differences. And here is my colorful revision to the star map in Imperium Galactum Later! DavidMil

Enjoyed the read Mark! Back in the early 80's my wife and I sent a lot of pictures and forts to a company that had a contest going. You may have heard of them... ClipArt. Anyway, after we sent them in (and never heard back), we bought a book and disk from them. And there in the book and on the disk, were several of our pictures. When we called ClipArt about it, they said that it was in the fine print in the rules that all submissions became the property of ClipArt. That was the first baby step for us; teaching us that piracy was a two headed axe! DavidMil

First let me say that I'm sorry to have been gone for so long. It's been a bad couple of years for me. Between floods, loosing a brother to Covid, and depression because both my wife and I are rather old and have compromised health and have been shut in the house for a year now; it just all got me down! Then Mr. Mclaneinc and The Doc sent me emails (concerned about me) and a lot of badgering from the wife, and now I'm back. So Hello Everyone. I've got a LOT of catchup reading to do. I've been cleaning up the 1200XL schematic's and I found several problems with the original ones. I'll post my cleaned up version tomorrow. Also found a couple of errors in the 835 revised schematics. I updated the Star Map in 'Imperium Galactum', which I can post if anyone is interested. And lastly you would think that a 69 year old man wouldn't get mad and throw his best joystick down in anger for getting killed over and over again in Zaxxon (a game which I was very good at 35 years ago), but I did. I was even madder(?) when I discovered that my tantrum caused the white wire in the cable to break. My wife laughed when I told her about it (which really didn't help matters)! Anyway, I'll get busy reading now. I hope everyone is well! David

How many different versions of Archiver are there? I came across a disk that has Archiver 2.0, and it allows you to copy to or from a cassette to disk. It also has an option to run version 2.0, or the version I remember 1.2. DavidMil

I had never heard of a resin printer before you mentioned them. I looked them up and they are very different. They use a light beam to activate the resin and cause it to solidify to a surface that is continually raised. A light beam can certainly be made much smalled than a extruder nozzle. Very interesting! They must be more expensive because all the sites that I looked at want you to call for a quote. David

Brad at Best Electronics was kind enough to send me a couple of Stackpole plungers. I'll be sending them off to get scanned too. Below is a couple of pictures of Stackpole (yellow) and Hi Tek plungers (white). David

Thank you Doc. I'll try and get them in the mail Monday or Tuesday at the latest. DavidMil

The modem had a bad TMS99532NL 300 baud modem chip in it. When I replaced it with my know good one it blew that one too. When I get a chance I'm going to start checking voltage first. In the mean time I've ordered 22 from UT Source for 72 cents each. Doc, can I send you all eight disks to look at? I've got more people coming next week to work on replacing some cabinets we have discovered have mold on the bottom of them. And to top things off, my middle finger on my right hand has developed 'trigger finger'. I didn't know it could make your hole hand hurt all the way to the wrist, and prevent it from closing tightly. DavidMil

I just bought a non-working 835 modem from eBay and it came with 7 floppies. One half of the set says DD at the top and my 1050 can't read them. All say BBSC Construction Set, or Docs, or Samples. Also half are marked 835 and the others are marked Smartmodem. Anyway the ones I can boot say: Antic Software BB Construction Set Ver. 2.2 by Scott Brause The one for the 835 has AMODEM 42, and TSCOPE, and DLINK Anyway, does anyone have any use for these Disks? If so I'll put Zipped versions out there (I just need to know where would be best). DavidMil

That is great! I can get about all the parts info from that. Thank you, David

Has anyone ever seen or heard of a 1090XL parts list? I've got some good pictures looking down on the board, but I really need a parts list. Thanks, DavidMil

It looks like they took a keyboard off of an old terminal (like a Vax or something), and tried to modify it to work with an Atari computer. David

I think that myatari might have a few left. You'll have to send Bruce an email and ask him. They will be NOS, but they will be in perfect condition. DavidMil

Are those numbers recessed, or a different color? David

Here are a couple of pics showing the original on the right and the new one on the left. David