TRS-80 Model III, Level I in the flesh.

[8Bit]

Last year, I acquired a working Level I Model III. (4K, with 4K keyboard badge, no disk-drives, cassette interface). It came with a Level I user guide, which is missing a few pages from the back.

It has the catalogue number 262-1061 and has the serial number of 0001545.

It’s a UK model, manufactured in Forth Worth, Texas according to the Silver label and the warranty seal is still intact.

The seller had bought it from a local Tandy store in Liverpool, UK back in the day and had used it until the C64 was released. He upgraded to a C64 and put the TRS-80 into dry storage until selling it on eBay last year.

A ROM Image has already been made (via cassette output) and has been passed to Knut Roll-lund for confirmation.

I'm posting here because I still can't find much info about this model on the Internet and it's becoming obvious this is quite a unique computer.

Does anyone have an estimate how many were built and sold? The serial number would suggest at least 1500+ could have been (and potentially sold in the UK?). Exactly how many still survive would probably be difficult to estimate.

I'm not here to sell, so I'm not concerned with its perceived value. I just thought I'd post to let you guys know these mythical beasts actually exist.

[Mike Y]

"8Bit" <ukretr...@gmail.com> wrote in message
news:634f60d9-a00e-4cda...@googlegroups.com...

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Not sure if I should admit this, but there were a surprisingly high number
of 4K Level I machines made.

A LOT of internal Tandy people bought 'basic' Model IIIs and then undated
them with parts. If I remember correctly, you could get the 3 separate ROMs
for about $20 instead of paying $100 for the Level II kit. (That was the
same with the later Model Is. Shop techs would 'swap out' their Model I CPU
boards so they could just plug in the later version of the Level II ROMs
since they were a 2 chip set.) 16K chips were much cheaper elsewhere, and
just as good or better. (Tandy took a batch of bad TI RAM chips that had
problems. The el-cheapo NEC chips in plastic worked great, and were cheap!)
As for the disk drive, the 'chimney stack' was about 5 or 6 bucks. Then the
FDC card and a power supply. Power cables were cheap through Tandy parts
too. But you always made the FDC cable (although you bought the main board
to FDC cable). Disk drives were available as raw drives all over the place
cheaper than Tandy. (Actually, the later Tandy drives were top notch!) Or
put in double sided drives. Same with the RS-232 option, you built it from
parts. Hmm, I can't remember if any Model IIIs didn't have the keypad, but
they was just snap-in switches and a bezel.

It took a while, and but when it started getting out of hand, Tandy quickly
restricted the parts to shops only, but that wasn't a problem for the techs
in the field.

Now, the REAL nasty upgrade was trying to make early Model IIIs RF quiet!

[8bit]

On Sunday, August 12, 2012 10:49:50 PM UTC+1, Mike Y wrote:
> "8Bit" wrote in message

Then maybe I've been fed duff information.

I was asked for a ROM image from my machine as verification of its existence. Prior to this, ROM images had been difficult to locate. I had been told only one other Level I Model III was available for imaging and the ROM image I created was used to confirm the previous image's integrity.

I'm aware others upgraded their Level I models to higher-spec. I think it's because mine is still a Level I machine it has been classed as comparatively rare. As I mentioned in my original post, it still has its original warranty seal intact.

So you're telling me the Model III, Level I is still readily available via the usual online resources?

[Mike Y]

"8bit" <ukretr...@gmail.com> wrote in message
news:efec5dec-ed8c-4782...@googlegroups.com...

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Oh, Model III Level I were still rare, compared to all the others. VERY
rare!

One of the issues has to do with the technology of the time. When the Model
I came out, there was a 3 month period where ONLY the Level I machines were
available. As a result, Level I got quite a following. When Level II came
out conversions were available for starting the machine either way. Then
when disk drives were available, there was even a loader for Level I,
although that never acheived the popularity of the switch.

By the time the Model III came out, Level I was at the end of it's life. If
it weren't for the fact that it was such an easy port to the Model III, I
don't think it would have been offered. Almost everything in the Model III
worked as default Model I from a Level I point of view.

You know, I wonder... I worked there but I can't remember if they used a
mask ROM for the Model III Level I or did it with EPROM? OTP parts were
becoming available at the time, so maybe they were used.

I also seem to remember that the Level I wasn't available at the first
release date, customers actually got the Level II first. But that may have
just been my perception. Personally I ordered a 'stripped down' Model III,
and I had to wait for it. But that was 30 years ago and I can't be certain
if I ordered it Level I or Level II. I do know it was 4K. Then I built it
up with all the parts into a disk system.