Jump to content
Have You Played Atari Today?
2600|5200|7800|Lynx|Jaguar|Forums|Store  

Ed in SoDak

Members
 View Profile  See their activity

  • Content Count

    785

  • Joined

  • Last visited

Posts posted by Ed in SoDak

  1. Posted

    As Popular Electronics began to wane and changed its format to lean towards computers, they first included it as a section, then went over to the new Popular Computing title. PE subscribers like myself had their remaining issues filled with PC. I wasn't into confusers yet, so felt it was a waste of my money. I may have had an extended subscription, as I recall having a number of back issues stored "out in the shed."

     

    It wasn't much different from any other computer rag of the day but a big departure from the old PE days.

    -Ed

  2. Posted

    Got the 1500 going again! New member TMA-1 (Ian) gave me his RAM tester program for the 1000 which was well-suited to use on the 1500 with a RAMpack to give it operational memory while the internal RAM lay dormant. That gave repeatable errors that pointed to the chip on data line D3. Traced that down to the suspect chip, removed and socketed it. When my new RAM chips arrived, I plugged one into the socket and the patient has a pulse!

     

    That doesn't answer how to test the RAM without power or out of circuit, but at least the 1500 is working again.

     

    -Ed

  7. Posted · Edited by Ed in SoDak

    The drives do spin up for a moment with enough oomph to rotate the floppy. If you wonder, try it with no disk, or with the latch only partly closed. That way there's less drag and you may be able to tell if it's weak or just part of the normal disk insertion. You could meter the 12v line, that's what runs the drive motors. If voltage takes a dump, that may be supply-related since you think the drives themselves pass muster. Only one motor should spin at a time. Two drives, even half-height, in a PEB is pushing it for the supply limits and it will lag in voltage a bit.

    -Ed

  8. Posted · Edited by Ed in SoDak

    I hear ya! I removed the RAM and socketed a TI once, and only once, and that didn't fix it! Moved it on as a parts unit and last I heard, it was still dead, though he tried mightily to get it going, as I had years ago.

     

    Gets me to wondering... I remember seeing test adapters that gripped an IC and brought all the contacts up for easy connection of test probes. Now, what if you could make a plug and short ribbon cable to fit a RAM socket installed in a Timex ts1000's RAMpack. The other end of the ribbon has that clippy IC testy thingy on it. (Highly technical terms!) The big IF is: if an IC can be tested "live" this way while in-circuit in another machine.

     

    The Timex is small and light and could be placed near or even on the TI motherboard to keep the cable short. Testing without desoldering would be a very cool thing for TI-ers and Timex or other confuser owners.

     

    Or maybe just a logic probe is all that might be needed but that probably requires the TI to be powered up for testing, which may not be easy or possible due to an undetermined fault on the motherboard.

     

    Probably easy enough to implement for a tryout. Hmmm.

     

    -Ed

  9. Posted

    Did these drives work as installed the last time they were used? If you just took a couple random drives and installed them recently, I'd check to make sure each drive was set up correctly to respond as DSK1 or 2 and also if the data cable was the right way around. Some lack a keyway and can be plugged in backwards, which casues the drive motor to spin constantly. Some cables have the Drive Enable pins lacking so they only work for a specific drive number.

     

    But if your system was unchanged from when you recall it as working, then that question has been answered at least.

    -Ed

  10. Posted

    Nice capability, if you happen to have one! I looked at programmers while I was shopping for RAM at Jameco. The cheapest used a parallel port and DOS, so that means I'd have to drag (yet another) old system out. It's cheap enough at about $300, but still too expensive for the limited uses I'd have. USB programmers probably don't support Mac and also cost quite a bit more. I could skip the testing, buy a lot of parts and sockets and still be way ahead of the game.

     

    But what to do with those pulls? ;) Right now, I'm taking the tack my Canadian friend Ian used. He made a purpose-built Timex setup with all socketed RAM just for the purpose of trying out various Unknown Status 4116 chips. A simple added circuit kept the internal 2k RAM active and remapped the RAMpack to a "safe" area for testing with software.

     

    I'm learning a lot along the way. While robbing parts from failed boards, I accidentally discovered one merely had a bad transistor, so I got another TS1000 working as a bonus. I'm trying to fix a broken RAMpack now to fit onto it. Hopefully this will spare the kinda scarce TS1500 and my working TS1000 from the ordeal of testing suspicious RAM chips.

     

    Such a setup could also be used to test TI99 VDP RAM chips. So far, I'm just having fun getting old stuff working again!

     

    -Ed

  11. Posted · Edited by Ed in SoDak

    Thanks for the reply! I'm working on a Timex TS1500, but the RAM is the same as in the TI.

     

    The tinfoil trick is funny, maybe if I wore a tinfoil hat too it would be even better? ;) A friend was testing them via software in a working ZX81 computer in a socketed RAMpack. He tried "hammering" the stuck bits by repetitively poking a number into specific memory addresses.

     

    I have a few pulls from a TI99 console, two of them immediately heat up the power supply transistor. Using the diode check on my DMM, I get different readings among these used chips, but nothing definitive so far. My TS1500 may have more than one bad chip, but poking/peeking the memory seemed to say the trouble was on the D3 dataline, so I started there.

     

    Looks like I may end up pulling all the RAM and installing new chips. Once i track down a good source, that is.

     

    EDIT: Got 16 RAM chips and other parts on the way from Jameco. Maybe I can get a RAM pack going too.

     

    -Ed

  12. Posted

    Would it be possible to test 4116 RAM out of circuit for possible shorts in the power pins? Maybe by using the diode check function of my DMM to the 12v, -5 and +5 pins to ground? I have a bunch of pulls, one of which may have a short. I'd like to be able to cull it out by means other than testing for smoke in an otherwise working console.

    Thanks!

    -Ed

  13. Posted · Edited by Ed in SoDak

    A lot of this stuff wouldn't be rare at all, except for the vast majority of it getting landfilled. Either that or a lot was hoarded but the owners are still living. So those "collections" may trickle into the pipeline or as often as not, dumpstered by the heirs as worthless.

     

    I held onto a ton of old magazines with hopes they'd be collectible someday. The weight estimate is probably accurate! ;) I have stacks of Nat'l Geographics going back to 1911 or so saved by my mom from her father. Plus probably thousands of issues of dozens of other old publications. Mostly electronics/computer/science/mechanics/radio. These days, with every old collection going into pdf, their value has dropped.

     

    Before the internet and even now, I'll just drag a stack of 'em into the house and I'm all set for a month or two of reading bliss. Stupid-high shipping has taken away any real advantage to trying to sell them online. Google-Nerd shows me as the only extant example in a 300-mile radius, so local sales are out. Friend Wife has previously told me it's all dumpster fodder to her, so I guess it boils down to either me dealing with it all at some point or it becomes compost.

     

    Too bad, because there's plenty of gold in the dross, but she wouldn't have a clue as to which was which! I'm valiantly trying to sort some of it out for dispersion and while the recipients are always happy, I meanwhile get all reabsorbed in the nostalgia of revisiting a collection and the project of dispersal stalls in its tracks. My play room ends up as crowded or worse after most any attempt at sorting it out.

     

    But I have to agree, even with publications I happen to have originals, I often go to the pdf of it myself just for the convenience. But for bedside reading, it's always the original!

    -Ed

    • Like 1

  14. Posted · Edited by Ed in SoDak

    Some Timex Sinclair models use the same 4116 or compatible RAM, plus other vintage iron as well. Sometimes you can piggy back a good chip by hand, but not so sure how easy or reliable that test is. About the only way I know of testing in circuit other than a short check on the power pins or feel for heat is substitution with a known good chip. Which usually means having a working system with one chip socketed for testing the unknown chips.

     

    Maybe the hardware gang has something better. I have a Timex 1500 with bad RAM, so I'm watching this thread as well.

     

    -Ed

  15. Posted

    I was gonna suggest swapping a working motherboard and keyboard into one case but the F18A answer is no doubt better yet! If the RAM chips don't feel hot like one or another might be shorted, you may be better off leaving them in. It's a lot of desoldering that has its own risks of board/trace damage. Or just swap in one of the working boards, but you'd have to reinstall the F18A into it.

    -Ed

  17. Posted · Edited by Ed in SoDak

    On the "good" keyboards, all you need do is pop off the individual keycaps. Start on one side and gently pry up with a small screwdriver under the bottom edge of a key, it'll pop right off. Inside, you'll see a pair of copper fingers that connect when the key is depressed. Your favorite choice of contact cleaner, or alcohol and a q-tip. Watch you don't leave stray cotton q-tip fibers behind, or use one of the foam types. Watch you don't deform the contacts so they no longer touch when they're supposed to. Those foam q-tips are maybe too thick, so be careful.

     

    Worst case, but also less risky with bending the contacts, take a thin piece of fine sandpaper, fold it so there's abrasive on the outsides of the fold and lightly burnish the inner faces of the copper fingers.

     

    That's it, you've cleaned one key! Have a beer and celebrate, then in just 39 more beers, you'll be finished! In more ways than one, I suspect. ;)

    -Ed

    • Like 3

  18. Posted

    I have a beige "non 2.2" in current use. I don't mind the look of the beige. I have two B&S that also served here for many years and still work. They all have the "real" keyboard with copper contacts. Pop off the keycap and there they are. A balky key gets a little spray contact cleaner and maybe a stroke or two with a thin, folded-over piece of fine sandpaper on the worst offenders.

     

    Used my TIs for journalism and much writing for over 10 years. I can type like a madman on the ol' TI k'board! It just fits me I guess. I'm not a touch typist since I put a finger into a Radial Harm Saw back in '79, I type with two or three fingers since then. (I can still count to 10!) ;)

     

    -Ed

  20. Posted · Edited by Ed in SoDak

    Shit, I live in a freakin' computer museum! Tours involve you helping me drag 'em out and dust 'em off to check for fresh sparks. (Nope, not ready yet, put her back. Next!) ;)

     

    So, now you have another choice: Bozeman, Glacier or Ed's Fabulous Shed 'o' Mystery!

     

    Would it help if I told you we're only 15 minutes from Mt. Rushmore? Ok, how about 12 minutes from Cosmos? 6 to the nearest Bar??

    -Ed

  21. Posted · Edited by Ed in SoDak

    The original ZX-80 only had 1k of RAM. A screen that was filled with characters took almost 800 out of that thousand bytes. Most programs did not fill the screen, but you get the picture. The program and the data it uses have to live there, too. Not a lot of room to work in. The ZX-81/TS-1000 bumped that to 2k. Any savings was worthwhile, even if only a few bytes.

     

    You really couldn't do much useful with it till you got the 16k RAMpack. I recall entering programs tag-team style with my brother and helping find where the heck some seldom-used token was on the keyboard. After awhile you memorized most of them. I got a refresher course in that recently playing with one of my old machines. At least they made "Delete" easy to get to! That's kind of an admission of their guilt right there, if you ask me!

     

    -Ed

  22. Posted

    I visited due to the link on the TI forum, so I guess the poll results are being skewed by the poll creator unless he's also posting lures on the other model-specific forums as well. ;)

     

    Started on the Timex 1000, got a TI and cassette a few years later, expanded that to typical PEB status and used that till I went to Mac.

     

    Bought an Atari 400 with a few games, but since it had no Basic cart, I eventually donated it years ago.

     

    Other orphans have shown up here; Osborne 1, Tandy PC, IBM PC, P2, Apple IIc, but I don't really use any of 'em, they just lurk in the dusty forgotten corners of my shed.

     

    -Ed

  23. Posted · Edited by Ed in SoDak

    I set up my Mac and TI for transfers back in the Mac Plus days when Mac used a DB-9 serial port. The TI end used the standard DB-25 modem connector. When Apple dropped the original-style serial connector, I wired up a simple adapter to convert the Mac DB-9 to the little mini-db such as used on the SE and all later ADB-style Macs.

     

    I used Z-Term on the Mac and Telco on the TI over a null-modem cable. Or the TI-equivalent, as its send/receive wires are already transposed as I recall.

     

    To use that same setup on a modern USB Mac, I bought a Keyspan serial-to-USB adapter. This arrangement works for Os9/Classic on any USB Mac, For osX, I updated the Keyspan driver software and Z-Term to OSx and once I got the settings matched in the new version of Z-Term, I was good to go using Xmodem to transfer files same as I always have since the 80's.

     

    So my cable's kinda odd, being able to connect to literally any Mac from the 128 to today's just by how many adapters are added on. Oh, there's a DB25 hanging off there too, to connect two TIs together. :grin:

     

    It's easiest to first create an ARCIII archive if it's more than a few files, or just send 'em one by one. On an ADB or older Mac, all you need is cable and software. For USB, it looks like you'll need some piece of hardware on one end or the other to do it and the proper cable, which is easy to roll your own with only a few wires to deal with.

     

    -Ed

    • Like 1

  25. Posted · Edited by Ed in SoDak

    If I did this conversion to 80-track, what happens if I put a 40-track disk in that 80-track drive? Would it read/write? Or would I be stuck with having to use 40-track disks in a 40-track drive? I'm not really shopping, just curious.

     

    I converted most of my old SSSD disks to DSSD long ago and don't add new files very often, so I'm content to use my 180k DSSD collection as it sits and skip the work of transferring everything to larger capacity just to trim the total number of disks I have. I was curious about going to a 3.5" drive just for reliability, but my 20-year-old collection of 5.25" floppies still seem to read/write fine, knock on wood.

     

    On other systems, sometimes the High Density disks are less reliable. Would a 1.4 meg drive on a TI be problematic down the road? Probably best to transistion to a hard disk or some solid state drive if you use a TI that much to require a ton of storage.

    -Ed

AtariAge
Forums
Store
General
Follow AtariAge

Copyright ©1998-2021 AtariAge

×
×
  • Create New...