ISO TRS-80 Model 4 upgrades

[bettablue]

As the title states, I am looking for upgrades for my TRS-80 Model 4 computer. I am currently upgrading mine with a 64K memory upgrade, and swapping out the 180K single sided floppy drives in favor of a pair of 360K full height floppy drives. What I am looking for are things like an amber monochrome CRT, to replace the original B&W CRT, plus any other undocumented upgrades I am not supposed to know about? Can anyone help me with

 

[Jay Newirth]

I really doubt you will find an amber monitor that will fit in the Model 4 case. Green screen is no problem (I have several for sale). You may want to consider a FreHD emulator card that will give you "hard drive" ability using SD cards. I have installed a fair amount of them in systems. As far as the floppy ... find (2) IBM PC drives on ebay ... but I would think what you have is fine if you go the FreHD card way. Hope this helps

 

[BartH]

Hello bettablue,

I'm not sure wat you want to achieve with these upgrades and why you keep repeating the same questions over and over again, but as it obvious you don't know very much about the Model 4. I'll try to answer most of your questions:

1. CRT. Tandy has only sold green and b/w CRT's in the Model 4. It might be that some amber CRT will fit, but as Jay stated, it is really doubtful. You won't find it here I'm afraid.
2. Video upgrade. I'm not sure what you mean but the Model 4 has a fixed video-controller that can't be exchanged. There is however a hi-res upgrade that gives an hi-res overlay over the normal screen. There is special software needed to utilise it, and it will only work on a few DOS'ses. Only usable when you really know what you're doing.
3. Internal Hard disk. There has never been an internal harddisk for the Model 4. You can try to find an external unit, or use the FreHD emulator. It requires knowledge of the Model 4 DOS's. It won't boot from the harddisk (e.g. you need a floppy to start the DOS) unless you exchange one of the ROM chips.
4. 360 Kb Drives. It can be done and it will work, if you know what you're doing. Especially Newdos80 will give you headaches. It is unclear what you think you will gain by this.
5. 64 Kb. It will give you a total of 128 Kb which is nice. The extra 64Kb can be used for a Ramdisk or spooler, and can be used in Scripsit. For normal programs it is of little use. Be sure to buy not only the memory chips but also the GAL.
6. There are no upgrades that you're not supposed to know about ;-) The official Tandy upgrades can be found on trs-80.com, where the modern upgrades can be found on Ians site The Right Stuff.

My message is: be careful with upgrades. The Model 4 is a fine and complete machine which will give you much retro fun. These upgrades will cost you serious dollars and can only be utilized with the right software, the right knowledge and the right skills.

Hope this helps! (And I hope I don't sound to negative)

Bart

 

[bettablue]

I want to thank all of you who passed info along to me, and my constant requests for more. My hope is that given my limited knowledge, and ignorance of the computer. I have learned a lot though. I just got hold of the TRS-80 Model 4 manual, and a copy of the original Tech Reference manual.

I’m definitely going to read both of my new manuals.

Lastly, I hope you all can forgive my ignorance. You have given me the help I needed while I needed it the most. So thanks everyone. Your help was/is invaluable. I still intend on upgrading the single sided floppy drives, and adding the 64K upgrade. These will double the floppy disk space, and with the memory upgrade will double the RAM from 64K to 128K. As far as displays go, I have seen a couple of TRS-80 Model 4’s with amber displays.

 

[hornbetw]

The CRT in the Model 4 is the same as the Models I & III. Amber tubes were available, but not from the Shack. I think Ian Mavric may have a few.

Tom

 

[Tibs]

Several of us have looked for the Ambers, you're going to be hard pressed to find one. I tried last fall and VDC still doesn't have any in stock, which is where Ian got his stock.

Also, this machine is 8 bit and the extra 64K will be in two new banks of 32K each that can be used for a RAM Drive, or a print spooler, or a task switching application (Best use in my opinion), so you can run two at a time. It doesn't multitask though.

Setting your expectations that the extra RAM is a neat things to have but not essential. The hi-res is neat but not essential or practical for every day use. The floppies however you would benefit from if you really need the storage.

Do yourself a favor and just get the FreHD or M3SE before you do anything else. You might never want the other stuff.