Opry99er Posted April 9, 2018 Share Posted April 9, 2018 I have finally acquired a TRS-80 Model III. When I was a kid, my buddy Eddie had one of these. I had a TI, and our friend Luke had an Apple //e. Needless to say, we spent a bunch of time at each other's houses. I now have all three in my collection, but don't have the //e set up right now (for reasons I won't discuss here). Anyway, I picked this machine up in a trade, and it settled in nicely in my dungeon attic. (Yep... it's exactly what it sounds like). So without further adieu, here is my system and its new neighbors. 6 Quote Link to comment Share on other sites More sharing options...
+sm3 Posted April 9, 2018 Share Posted April 9, 2018 Wow, in the box too! The Model III looks great! You have quite the collection of machines and software as well Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Thanks! The top drive isnt working, bottom drive is somewhat flaky, I am fairly confident the caps are about to pop, and the contrast potentiometer is frozen up, but these are all fixable!! The important thing is that it is structurally sound and functional enough to test things with. Soon Ill have a wicked beast of a machine with a blazing 48k of CPU RAM, a fresh aluminum paint job, a brand new set of XCaps and Analog caps, two working drives, and a PC interface of some kind (havent decided which direction to go yet). Also want to get a NOS green CRT to really freshen it up. But that is just vanity. Quote Link to comment Share on other sites More sharing options...
+eebuckeye Posted April 10, 2018 Share Posted April 10, 2018 Never seen the box!! Nice!! 1 Quote Link to comment Share on other sites More sharing options...
+sm3 Posted April 10, 2018 Share Posted April 10, 2018 You could install an auto-boot ROM and have your drives optional, just use a FreHD or M3SE. I've done that with my Model 4, works great. 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Good suggestions! FreHD looks a WHOLE LOT more affordable than the M3SE... Im sorry, I wont spend $300+ on a little PCB with modern components on it. Cant do it. Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Hey sm3, where would one find an auto-boot ROM? Would it be burnable with a MiniPro? Quote Link to comment Share on other sites More sharing options...
Turbo-Torch Posted April 10, 2018 Share Posted April 10, 2018 Drives will probably need an alignment, which will require a scope and a program like Floppy Doctor. I have DS Tandons in my original Model III which are aftermarket. Also have a spare Model III with factory SS Texas Peripheral drives which are a cheap version of the Tandons that Tandy decided to use. Those drives have one thing in common which drove me batshit crazy, and that's a setscrew on the stepper motor shaft that magically loosens itself over the years. Both makes, all 4 drives...get things aligned perfect on the scope, read/writes perfect on all tracks and then anywhere from a few days to a few minutes, everything is botched up again. Turned out that stupid set screw was loose on all 4. Once secured and aligned again, all have been working perfect for years now. 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Wow... that may be what is wrong with my top drive.... And potentially why my bottom drive is hit or miss... Quote Link to comment Share on other sites More sharing options...
+sm3 Posted April 10, 2018 Share Posted April 10, 2018 Hey sm3, where would one find an auto-boot ROM? Would it be burnable with a MiniPro? I didn't burn the ROM myself, I purchased mine from here: http://bartlettlabs.com/M3SE/pricing.html just had to install it and I was done, which I like You can download it from here though: http://members.iinet.net.au/~ianmav/trs80/downloads.htm 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Thanks for the info! Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Drives will probably need an alignment, which will require a scope and a program like Floppy Doctor. Out of curiosity, I use full height 5.25 drives in other systems... Ive never had to align the drives. Should I look for a matched set of Shugarts or Mitsumis to replace the current drives? Quote Link to comment Share on other sites More sharing options...
Turbo-Torch Posted April 10, 2018 Share Posted April 10, 2018 Out of curiosity, I use full height 5.25 drives in other systems... Ive never had to align the drives. Should I look for a matched set of Shugarts or Mitsumis to replace the current drives? I've not tried a different brand other than a TEAC, but if you have some spares kicking around, I'd give them a try. As far as those screws, I don't know what makes them loosen up. The Tandons have been in my Model III for over 30 years and it was after several years of non use that they got out of whack and were surprisingly loose. The other Model III I bought a few years ago was an all original fully loaded unit that looks like it had never been used. Same issues. I personally like the look of the original full height drives, but you can stick something in there like up to 4 half height TEAC drives if you wanted. Odds are your Texas Peripheral drives will be perfectly fine after a tune up. Before attempting alignment, give them a good cleaning. The grease on the track bars hardens up and the stepper motor can't operate (this may be part of the set screw issue too). Clean all that off with rubbing alcohol soaked q-tips and relube it. Of course check that the belts are still there and not slipping. They're usually fine as they're nothing like rubber belts in audio equipment. Next check the speed. There are two patterns on the flywheel, one for 50hz and the other 60hz. When spinning, the 60hz pattern (in the US) should appear stationary when viewed under a fluorescent or neon light. This has to be an old school fluorescent light with a starter can, those modern curly deals don't work. If the pattern looks like it's moving, you can adjust a pot until it appears to stop. You definitely need to clean the heads. If you don't have any of those old cleaning disks, you need to find some on eBay. Floppy disks are getting old and leaving more behind, so you'll be cleaning much more than back in the 80s when everything was new. If after all that, you still have issues, it's time for an alignment or good used drives. Guaranteed tested drives are getting pricey, figure on $50 each if you want to settle for one with an IBM logo on the front. This is an excellent source of repair info on these drives. https://www.classic-computers.org.nz/blog/2010-06-28-alignment-tandon-m100.htm It's for the Tandon brand, but the Texas Peripherals (which you probably have) are very similar. Test points are different, and RS used two different series over time, so you'd need to buy or download the Model III Technical Reference Manual to figure out where to hook up your scope's leads. With a bit of info from the manual and that site, it's possible to get perfect alignment without the impossible to find alignment disk. Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 10, 2018 Author Share Posted April 10, 2018 Great info! I do have a cleaning disk. So Im good there. I can also clean and re-lubricate rails (have done that on my TI drives many times over the years). IIl probably swap the non-working drive for my unused Mitsumi SSSD drive... looks just about identical to the ones in there. If it works, Ill do some work on the one I pull out... see if I can get it back to its former glory. Thanks again! Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 15, 2018 Author Share Posted April 15, 2018 So, a bit of progress to announce... I picked up my Aluminum paint and my 300 grit sand paper... also grabbed a soldering iron and some solder, as I plan to replace the X2 RIFAs when I crack the case. Beyond that, its just a waiting game for when the weather breaks (currently in an ice storm and 30 MPH winds) and when my work bench is clear. I am currently making up a few cables and doing a battery replacement on some components for my TI-99/4A. When the weather clears up, Ill be able to do the paint job in my covered porch area. Quote Link to comment Share on other sites More sharing options...
Asaki Posted April 15, 2018 Share Posted April 15, 2018 Here I was, thinking "A New Day Dawns in Wisconsin" was a really cool name for a homebrew game. 1 Quote Link to comment Share on other sites More sharing options...
+sm3 Posted April 15, 2018 Share Posted April 15, 2018 So, a bit of progress to announce... I picked up my Aluminum paint and my 300 grit sand paper... also grabbed a soldering iron and some solder, as I plan to replace the X2 RIFAs when I crack the case. Beyond that, its just a waiting game for when the weather breaks (currently in an ice storm and 30 MPH winds) and when my work bench is clear. I am currently making up a few cables and doing a battery replacement on some components for my TI-99/4A. When the weather clears up, Ill be able to do the paint job in my covered porch area. Be very careful when lifting the case for the Model III or a 4. There neck of the CRT sits pretty close to the metal shield covering the PCB and wires. It's easy to get it caught while lifting if you are not careful and break something. I'm pasting this video below from Ian Mavric explaining the process. Forward to about 4:58 for that part or you can just watch it all Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 15, 2018 Author Share Posted April 15, 2018 Thanks! I have watched his videos many times in preparation for this *procedure*. He is an excellent resource and a wealth of information. I need to clone him and make the clone open a repair shop in my town.... then I would apprentice at said shop, and one day after my 20 year apprenticeship is up, I will be able to confidently say that I know 37% of what Mavric does about the TRS-80. Quote Link to comment Share on other sites More sharing options...
+sm3 Posted April 15, 2018 Share Posted April 15, 2018 Thanks! I have watched his videos many times in preparation for this *procedure*. He is an excellent resource and a wealth of information. I need to clone him and make the clone open a repair shop in my town.... then I would apprentice at said shop, and one day after my 20 year apprenticeship is up, I will be able to confidently say that I know 37% of what Mavric does about the TRS-80. My Model 4 needed some power supply rework when I first got it and purchased one already repaired (caps) from Ian. I just wish he was closer due to shipping speed Quote Link to comment Share on other sites More sharing options...
Iwantgames:) Posted April 15, 2018 Share Posted April 15, 2018 My Model 4 needed some power supply rework when I first got it and purchased one already repaired (caps) from Ian. I just wish he was closer due to shipping speed Yea Im waiting on parts from Ian myself. Great guy but why does he have to be in Australia lol Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 15, 2018 Author Share Posted April 15, 2018 Maybe we could pool our money and get him to move to the US. Iwantgames is in Florida, Im in Wisconsin...... I think Chicago is a good mid-point. Quote Link to comment Share on other sites More sharing options...
Iwantgames:) Posted April 15, 2018 Share Posted April 15, 2018 Maybe we could pool our money and get him to move to the US. Iwantgames is in Florida, Im in Wisconsin...... I think Chicago is a good mid-point. Lol Quote Link to comment Share on other sites More sharing options...
Zonie Posted April 15, 2018 Share Posted April 15, 2018 Had a room full of 'em in High School... Quote Link to comment Share on other sites More sharing options...
pacman000 Posted April 21, 2018 Share Posted April 21, 2018 Glad the monitor didn't implode. Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 21, 2018 Author Share Posted April 21, 2018 Right?!! That was my concern all along... 1 Quote Link to comment Share on other sites More sharing options...
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