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Texas Tandy restorations

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About Texas Tandy restorations

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  • Birthday 11/07/1966

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    Houston, Texas

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  1. Tandy CM-11 with original Box - For Sale by Me, asking 150$ USD, perfect working condition no panel damages. Pick up preferred but will ship for 65$ US continental. PayPal or Venmo Accepted. Contact me Directly Here or by email: [email protected]
  2. So, I bought a coco 1 on auction, and it works fine 64K upgraded as well (yes it runs OS/9 L1 V2.1 and Sailor Man just fine. ) More to the point the problem I have is the joysticks did not work at all (joystick calibration program shows no activity (yes tested joysticks on other machine)) So I looked into technical Bulletins and found CC:006 that if memory > 32K then C57 & C58 should be changed from 0.01uF to 0.005 uF to prevent keys F/G and O to not work. (which in my case G /o are not working on keyboard) and I did the changeover, but the keyboard situation did not change. I also found R50 resistor to read 148 ohms instead of 100 Ohms and I replaced that one as well (part of the joystick circuit) Tests performed: I can trip pin 1 and 16 on the main keyboard connector (bypassing the keyboard) and, I get no reaction for expected "O" key, same for "G" oddly enough I can trip pin 1 and 10-11-12-13-14-15 on the connector and I get properly B,C,D,E,F To show on the screen, same goes for pin 2 with 10 through 15, and of course one could suppose 16 was bad, but no, pin 4,5,6,7 and 16 react to give me the W etc. and since its a matrix type keyboard I am confused. The only thing I can see on the diagram is pin 1 and pin 2 are also joystick fire button switch 1 and 2 (right and left joysticks) on the 6821 chip on PA0 and PA1, thus sharing a "line" and is possible to be bad internally. I cannot just swap out the 6821 because of a 64K upgrade that wires 6821 and 6822 together right now . I will order another 6821 and double socket it to keep memory mod but able to swap 6821 if it fails again later (if guilty of being bad) Looking deeper in what a joystick does, the sw1/sw2 fire button ground pin 4 to pin 3 of the joystick port, this made me lookin into pin of the keyboard connector, as per the diagram for "joysticks" and I tested at joystick port with power on, pin 3/4 to be grounded and the answer is No. I have ordered MC6821P replacements but will not be here before next week. Any other idea how to test the 6821? I cannot type letter "O" so I cannot run any joystick calibration to see if sw1 and sw2 are triggering all the time. Thoughts: Also when that joystick pins 3/4 grounding happens, then on the motherboard side, the inductors marked L2/L3 are triggered . My only problem is that L2/L3 of a value of 3.3uH. I just have not figured how to test them yet and if I can actually find replacements for 8479005 inductors as I dont know if they are Coiled, Choke or Toroidal inductors (see picture if you know) And yes this joystick problem is related to the keyboard issue of those 2 keys becauise if you look at the diagranm below you will see sw1/sw2 are connected to pin 1/2 of the keyboard matrix/6821 connections of line1/2. help?
  3. 1. the model 3 power supply information is found in the Model 3 service manuals I uploaded it at the archive.org web site for you : Model 3 Service manual: https://archive.org/details/model-3-service-manual-1980-radio-shack Model 3 technical Reference: https://archive.org/details/model-iii-technical-reference-manual-1981 Sams Computerfacts TRS 80 Model III: https://archive.org/details/sams-computerfacts-trs-80-model-iii-1985-howard-sams 2. the model 3 uses 2 power supplies instead of a single power supply like the model 4 later does. 3. these models of psu only have a single Rifa capacitor.
  4. on Ebay posted for 550 starting price. https://www.ebay.com/itm/134083771349
  5. **Tandy 1000SX - Main computer for sale. Houston, Tx Region - Asking 750.00 USD.** **Updates and additions:** 8088 CPU upgraded to NEC V20 Added 8087 math co-processor Upgraded memory from 384K adding 256K to get a full 640K of ram Added Tandy 1000 Smartwatch by Cybernetic systems Added a Multi I/O 2 Serials (db9 and Db25), 1 Centronics printer port Added an 18MB MFM D220 Hard Drive Added a Western Digital WD1001 8Bit ISA MFM HDD Card Replaced faulty Floppy Disk controller with newer NEC D765C Chip **Also included with the computer:** A Tandy MMS10 speaker box with cable A Tandy CM-11 Monitor with Original Box Two Tandy pro joysticks A Tandy 1000 Keyboard, the "ENTER" key sticks a little. A Tandy 5.25" Diskette box with floppies A Tandy 2 Button Serial Mouse A Hayes v90 9600Baud External model w/ PSU **The System comes pre-installed with:** MS-DOS v6.22, CTMouse, SMWCLK (smartwatch for date and time). Deskmate 3.05, Battle chess, Qix, Space Quest, Thexder, Arkanoid, Kings Quest II, Microscopic Surgeon. Price is negotiable, All questions or bids to be sent via Private Mail here or email: [email protected] Price: 750.00$ USD. Shipping will be expensive (contact for price with address/zip code), no international I would much prefer to do local pickup or delivery up to 75 miles from Houston, TX. (no cost) The payment method is PayPal. So, all parties are protected, an invoice will be given, and I'll pay charges. This, of course, all things being 40 years old, I do not make, nor suggest, any returns are accepted, or warranties are implied, this is to be considered an AS-IS sale. The only cable not provided in the sale is the modem cable (rs232C male-female) As seen in the photos this was a complete teardown and rebuild from the bottom up. Photos and videos can be viewed at this link: https://drive.google.com/drive/folders/1gcQXd2gG951wAOoPO7iFXP5tx76-4Jgy?usp=sharing
  6. are you using a Radio shack cable or a ibm Centronics ? * they are not pinned the same * i would check the pin out on the printer connections vs the printer port on the Model 4 (found in the service manual) my bet its not a 1 to 1 pin out.
  7. I compiled and date organized the Delphi Message boards for TRS-80 and Tandy forums from 1988 to 1994 into a searchable PDF file. it can be downloaded from https://drive.google.com/file/d/1hLMLN2oRHRQckwsRYV0EhSFcKJcO-8L6/view?usp=sharing
  8. just type system (sysgen=off) and it will go away but you can load any DSK/DMK/IMG/HFE disk image you may have with TRS80G which is nice when you do work like I do of copying original diskettes to Goteks to conserve them so it permits easy testing.
  9. Yeah I started using FTP Voyager a while back, neither google or Edge support ftp now.
  10. here you go all the Tandy 1800HD setup files can be found here https://drive.google.com/file/d/1uZjKbnbSXW03DXblXJNUWQb-VbpuuXYK/view?usp=sharing
  11. For quite some time I have been wanting to create a TRS-80 just for me. So I started with a TRS-80 Model 3 case skin set - Repainted shiny Black - Installed a Model 4 TRS-80 Motherboard, FDC and RS232C - 128 Kb of Ram (to be upgraded later to 384K) - Installed a"Langley St-Claire" Green CRT - Two half-height floppy drives "JU455" (360k) from Panasonic with full faceplates - changed as many keys on the keyboard to be as black as possible Starting to look like this: But continuing on the "Black and Green Theme", I started adding Green LEDs under the keyboard Other things still to be done or considered: - Green LEf Lighting of the underside of the case - High-resolution Graphics card - Matching External FREHD + Gotek unit - Two Speakers of 3 Watts, and Amplifier mounted internally with earplug jack and volume control. (Possibly) Orchestra 90 Music Card (Possibly) TTKL to VGA Video card with external connector to plug in VGA Monitor. more to come...
  12. Tested and reviewed a new game for Models 1,3,4 check it out... https://texastandy.blogspot.com/2021/03/roundup-latest-trs-80-model-1-3-4.html
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