The Tandy 1000 SL
//I AM ERROR
Where was I going with this? Oh Right! Memory errors....
I Suggest reading through Part 1 and Part 2, where we went over the history and specifications of the computer, as well as a thorough cleaning. When we last left off the Tandy was powered on for the first time since the about 2001. To my horror I saw this screen. I knew that it would have issues, but old RAM and me don't get along and after tearing pads off an Apple //c while replacing a bad MT4264 chip I was was reluctant to want to replace memory on this computer. However, luckily for me, all the chips were socketed!
Once Inside I proceeded to perform the Apple II style of troubleshooting like I did with my II+. Reseat EVERY chip. This required removing the drives and the Power Supply and finding a way to fit my tools under the drive caddy which is spot welded to the case frame. But with enough finagling the chips were persuaded out of their sockets and contact cleaner was sprayed liberally before reseating the chips.
I left the cover off so when I turned it back on I could continue troubleshooting...
Awwwwww still nothing.
So back inside the machine I began by removing the 256K RAM upgrade which, after speaking to my father he spent about $300 US to install memory upgrade bringing it to 640K. Which is the memory ceiling of the computer. Who would ever need anymore than 640K, right? Well, no cigar, the next steps were painstakingly swapping all the chips one by one until something worked well first one I swapped changed the screen! Except...
Still an error, but at least it showed more information. At this point I noticed it was after Midnight and that I was getting incredibly tired. I figured it would be best to sleep on it. Maybe a solution would come in a dream or something...
When I woke up in the morning I immediately jumped into the Tandy, with a fresh cup of coffee of course. Well sleeping on it worked great because I noticed the original 384K in the machine was MT4067's. Ahhhh Micron Technology the source of many cheap RAM chips that seemingly fail so often for absolutely no reason in vintage computers. Once I realized this, I promptly swapped the chips for the 256K I took out of the upgrade slots. Once all the MT chips were replaced with the compatible Sharp LH2464's that my dad paid so much for I turned it on crossing my fingers.
To my amazement it actually worked! These machines came stock with MS-DOS 3.3 loaded into a ROM. To use any programs other than COMMAND.COM and FORMAT, you need a supplemental disk though. But it did allow for a very quick boot process! So seeing the DOS Prompt was so exhilarating. However I wasn't finished with it yet. I proceeded to cycle it testing each of the chips until I found the culprit.
Look at him sitting there. Mocking me... I have since ordered a full RAM compliment of 41464's to replace all the MTs before they inevitably fail. After asking on the VCFED forums a nice member informed me that Jameco still sells these chips news. How amazing is that! $26 bucks later and in about a week, I'll have the computer almost fully sorted. My father told me he had a 48MB hard card in the computer, but when I opened it, the card was nowhere to be seen. Oh well you win some and lose some. My plans for this computer is to give it new life as an early DOS gaming computer to play THEXDER, Zeliard, and many others, like this computer was designed to do! I have plans to install a Gotek floppy emu, and maybe an XTIDE. An 8087 FPU would be pretty sweet too, but for now Let's just admire this computer from a bygone time. Oh and I tried everything to get this computer to recognize memory between 384K and 640K, It's not possible on this. So I have to wait for the 256K to come in the mail.
Oh before we end this, here is Colossal Cave Adventure playing in CGA mode. This screen took 15 seconds to draw, but looks stunning on this display. I definitely do not take my i5 computer for granted. It was a simpler time. When I get the upgrade kit in the mail I'll post another update on it. Today I had a 3 hour call with my father talking about the machine. He said he spent $1,100 in 1989 for the computer, $300 Dollars on the RAM upgrade, and close to $600 dollars on the hard card in 1990. That would be about $4,100 today adjusted for inflation!
Until next time.
Wait....
I did notice one problem with the monitor that I have to figure out how to fix. The screen curves inward. It's more noticeable in person so I have to figure out that out for next time it is especially annoying in Deskmate. It wouldn't be the first time I've messed with a CRT though.
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