Apple Thermal Transfer Printer aka Iic Scribe repair and cartridge info

[Elemenoh]

I've had an Apple Thermal Transfer printer on the shelf waiting for repair for a while and decided to dive into it.

It powered up but then something started smoking. Uhoh! It looks like at least one electrolytic capacitor (C27) severely leaked and may have damaged a nearby ROM.

Before digging in too far I pulled out the thermal transfer cartridge to see if it'd be replaceable. It looks proprietary on the outside, but is pretty simple inside. It uses 8mm wide thermal transfer tape. The spindles rest in openings in the enclosure. Those spindles are about 26.5mm OD and 24mm ID. I wasn't able to find similar tape online. If anyone who reads this knows of a source, please post a reply.

I haven't found a service manual online, so will be slowly taking it apart to repair the logic board and attempt to get it working again. I'll update this thread with progress.

 

[Elemenoh]

Well, this isn't good. It looks like the cap managed to leak all over the ROM. I managed to get it out of the socket while only breaking two pins. I'm hoping it'll work well enough to dump. Fortunately replacements are cheap.

 

[Elemenoh]

There was a lot of crust on the ROM pins! I used a USB rotary tool to scrape away the crud down to the shiny metal. A couple more pins broke off in the process. I soldered some leads on and by some miracle was able to get it to dump. the ROM dump is attached here, but not sure yet if it can be trusted. I've ordered a replacement EPROM so it'll be some time before I know for sure. In the mean time I'll replace the ROM socket and electrolytic caps on the board.

 

[eric]

Even printers ROMs deserved to be archived - right @Mac84 ? Good work @Elemenoh !

 

[Mac84]

Wow, excellent work trying to get this back up and running! I can dump the ROM from mine to see if they match.

The one ribbon I have always snaps unfortunately. If I tape it together it snaps again…

 

[retr01]

@Elemenoh, can you take picture of the cartridge holder assembly for the Apple Scribe thermal printer? I am trying to see about compatible ribbon cartridges. Sometimes some things are still used today after 30-40 years, usually in an industrial setting.

For example, certain Canon ink cartridges work with the Apple StyleWriter printers.

I see the picture of the ribbon cartridge, but I am wondering about any specific markings in numbers or words on it?

 

[Elemenoh]

@retr01 no helpful markings that I see.

 

[Elemenoh]

This is going to require trace repair for almost every ROM pin.

 

[retr01]

no helpful markings that I see.

Actually, @Elemenoh, it is a good start! Can I see the bottom of the cartridge as I'd like to compare with generics or other brands over the years see if I can catch.

 

[retr01]

By the way, just by using the top picture of the Apple thermal ribbon cartridge, I was able to find this within two seconds.

2 x Ribbon Apple Scribe IIc Thermal Transfer Printer TEC 800 1000 BLACK | eBay

Ribbon Manufacturing ....DIRECT SALE - best quality - low prices !!! Example image: TTR band 8mm in black 2 pieces Ribbon / ribbons Group 400 - TTR Tape - Applescribe 2c Can be used in the following office machines / printers: - Apple Applescribe 2c - Apple Scribe IIc - C. Itoh TPX80 - TEC...

www.ebay.com

 

[retr01]

And from that eBay listing, we learn of some hints:

group 400 - TTR Tape -

black 8mm

Group: 400

Applescribe 2c

TEC 800 1000​

 

[Elemenoh]

Thanks @retr01!

The 28-pin ROM needed 33 trace repairs. All but two needed 40 AWG wire to make space for the socket pins. It was fiddly work but kind of fun to do. I got the replacement ROM and ROM eraser. The eraser I ordered has a euro plug which is weird. It came via Amazon next day delivery. Why would they have those in the US? Anyway, I need to change out that plug, erase and program the chip before the printer is ready for testing again.

 

[Elemenoh]

I programmed a ROM, popped it in and put everything back together. It didn't blow up which is nice, but the head is just clicking and lights are flashing on and off. Anyone know what this means? I'm still suspicious that the ROM dump may be corrupt.

@Mac84 Would you be willing to dump one of yours?

 

[Elemenoh]

Here’s what It’s doing at the moment. Theres no change if the top cover micro switch is activated.

 

[XodiumRetro]

So I ripped apart my pretty busted up Scribe to find a TEC chip on it. Markings are TEC 7293-9137 EC-9137 8427AAA JAPAN

This is the dump from that chip, taken in Xgpro with a TL866II+, though because the TEC chip wasn't in its database I set it to the Intel D27128. So your mileage may vary.

 

[Elemenoh]

Thanks so much @XodiumRetro !!

That dump is identical to the one I posted previously, so that rules that out as the culprit.

I guess the next step will be going back to check my work on the board. Ugh!