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Tandy 1800HD

C

creaky286

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Joined
Oct 31, 2012
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I know it's bad form to start a new thread with my first post, so please pardon my audacity!

I just purchased a Tandy 1800HD at a hamfest ($5) for sentimental reasons - I always admired them back in the day when they were new and I was broke. It even came complete with a Tandy 9624V modem, user's manual and Deskmate manuals (but no media).

This one works (mostly) with a few caveats:

1. The original EME-263MG floppy doesn't seem to want to spin up at all.
2. The NVRAM battery is dead (replacement on order).
3. The 20MB drive has been replaced with a 3.2GB IBM unit that only works if the NVRAM has been allowed to die completely. If the setup180 program on the drive is run, it will no longer boot, regardless of the settings.

I know from reading leeb's posts and blogs that it is related to the 2810HD and Panasonic CF-270, but I keep running into dead ends when procuring schematics and/or service manual PDFs (I have scoured the Radio Shack support site for what little they did have) for any of these machines - any help here would be much appreciated.

Has anybody managed to get any other drives (HD as well as floppy) to work on these little machines?

Thanks!
 
First, welcome to the forums. Not at all a bad form.. it's a legit on topic question and it's actually vintage! wohoo! ;-) Great find. Which hamfest were you at?

I'm guessing you've probably already found radioshack's support site on your 1800. Is that a typo with number 3? Only runs if the nvram battery has been allowed to die? You probably need a drive overlay program for a drive that large which might be the issue. I think others here have had more experience with that and suggestions (or search around the forums, I know there have been some previous threads).

Not sure about the floppy drive. You could check the power source/cabling but it might default to the hard drive and never try the floppy (guessing).
 
I found it at the Carroll County (MD) ARC hamfest held a few weekends ago - a nice one to end the season on around here.

And no, it's not a typo. Very strange behavior indeed! If I run the setup program so that the initial scrambled NVRAM warning does not show, it fails to boot, claiming a non-system disk has been inserted. The floppy re-homes its heads as normal, but that';s about all that happens. If I unplug it and let the contents of NVRAM dissipate, it will boot (after the complaint about invalid configuration).

I'm thinking of brewing up an adapter between the 26 "pin" flex-cable connector and a regular floppy (if that's possible). One of
the files in the Radio Shack site seems to spell it out (but without a schematic, I can't be sure). I have lots of flex cable - some of it I harvested out of a worn-out Sony tape deck, so I should be able to brew something up if the signals between the two are compatible...
 
Have you pulled the drive out yet? Im CERTAIN you will find that the belt has disintegrated and is mostly-melted into pieces...
On my first one, it sounded like a jet engine spinning up when activated (cuz the motor was spinning only itself..)

If you do a google on panasonic FD belts you might find the guy I bought my spares from...

If not...

I would consider parting with one of my spares.

So you got a good MODEM??? VERY Jelly here! The only one I lucked upon existed in a machine SO GREEN I thought it was a leprechaun! :eek:

Once you get the backup battery installed, you will want to avoid using the setup program... as you have seen... unless you use the Drive Overlay method already mentioned. It will have to be 'reset' EVERY TIME as the software makes adjustments to the CMOS-stored BIOS settings...

Also... INTERLNK.exe and INTERSVR.exe are your friend... probably the EASIEST way to transfer back/forth when the floppy is down!

Cool beans, dude!! :D
 
Hey leeb!
The modem is an external unit, so it's not so cool as that. It's just a generic plastic box with an RJ-11 and a DB25 on the back.
I saw the belt under there - I'll google around and get some spares - thanks for the tip!

I think the drive that's in there was just partitioned into a single 20 Meg chunk, with the rest of it left alone. I don't know how compatible that is with what the BIOS expects.
 
GAWD!!! What a waste... 20Mb on a 3GB drive! :eek:
The drives I could not do surgery on were replaced with various sizes... a couple of them were 1.?-giggers...
Find a Drive Overlay for the brand of the drive and you will be able to make it hold LOTS more... BUT SAVE THE STUFF FIRST!!!! :p

IIRC 2gb was the 2nd drive 'limit' so if you ended up using a DDO, 2gb is likely the largest drive it would build...

Oh... external modem... yawn. :p
The belts I got were supposedly for a MIDI device floppy drive... but they work perfectly!
:D
 
leeb,

By reading your threads/blog I see you managed to scare up a schematic for a 2810 - can you point me to your source? Or perhaps send me a copy? :)
 
Not sure how much help they would be... there are alot of differences between the 2810 and the 1800...

However, PM me your email and we will see if I can send it... The PDF file is around 10Mb.

Lee
 
OK - I finally have some time to mess with the 1800 again - I received the replacement battery (from Hong Kong - took long enough!), but I won't put that in until I've figured out how to clear the NVRAM without removing it. I pulled the belt out of the floppy, and it is definately bad - it's too stretched out and won't grip the spindle tightly enough to spin the disk. I'll try measuring it out and ordering one or two from Ken's Electronics...
 
This 'weekend' (Monday most likely) I'll dig mine out and see if I can remember how to 'short' the CMOS...
There is a a jumper... dont remember where.
:D
 
Thanks for the manual - the CF-270 is similar enough to the 1800HD to help with the mechanics of the computer at least. I suppose there is a CF-170 out there as well, and it's probably the same thing as the 1800HD.

Anyway, I measured out the stretched-out belt, and I got this:

Circumference: 8.6 inches
Width: 0.1 inches
Thickness: 0.015 inches

I've ordered a replacement - we shall see what Ken's can come up with...
 
Well that's a bummer. The belt I ordered from Ken's worked, and the floppy spun up, but still no joy. Upon examination of the drive I noticed that the upper head was missing entirely! I guess somebody forced a floppy into or out of the drive and broke it. Oh well - now I get to monitor eBay for another EME-263MG.
 
Hey creaky286,

I have a dead 1800HD, give me a day or two to dig it out and see what's still attached to it.

It does have the internal modem, I remember paying the "big bucks" for that.

Anyway, more info soon.
 
So far I've found most of the parts of the 1800HD, it's missing the HDD, battery and modem.

I have the FDD but of course the belt is bad and the ribbon connector is damaged. Heads appear to be ok. The FDD worked fine when the video output quit working some 10+ years ago.

I'll keep an eye out for the modem, it may turn up yet.
 
Might you be willing to part with said 1800HD? I could use a parts donor! Send me a PM if you want...
 
PM sent, but I'm putting some info here, too. Just in case you do like I do, make a quick check on the forum without logging in.

Anyhow, the 1800HD is ready to be boxed up for shipment, only need a shipping address (send by PM for maximum security).

IMAG0173.jpg

The box will include:

1800HD main unit with all trim pieces
FDD
ribbon connector for HDD
original 20 MB HDD (tested today, not working)
manuals
AC adapter (tested today, working)
MS-DOS 5.0 for Tandy 1800HD (two 3.5" floppy disks)
DeskMate for Tandy 1800HD (two 3.5" floppy disks)



Will NOT include:

RAM
Modem
Battery
Mounting hardware for HDD


I bought this unit brand new in 92 or 93 (don't remember exactly) and used it until the video quit. By that time it was obsolete and Radio Shack wanted about $300+ for repairs. Bought a Compaq Presario 1610 in 98 which I still have and still works.

Don't really know why I dismantled the Tandy, just because I could, I suppose. Looked for the modem for quite a long time but it's so small and I have such a vast amount of junk, err, treasure, that it really is like looking for a needle in a haystack. Perhaps I'll come across it when I least expect to.

Cover the shipping and it's yours, I'll send it as soon as I have a shipping address (and a day off work).

Kent
 
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