Recent content by bzotto

FWIW, there's an outfit in TX that manufactures premade replacement pads for these keyboards which makes an reliable overhaul relatively straightforward and cheap: https://texelec.com/product/foam-capacitive-pads-keytronic/?highlight=foam (I used one of these kits for a PET once some time ago to...

No personal experience with it, but my understanding is that the iCOM (later Pertec) FDOS software was released as a handy complement to their various drive hardware offerings. I don't think they had very broad uptake. There were a couple revisions and I think FDOS-III was the latest. Here's a...

I do not have an Amiga 1000. Yet a few years back, through an unexpected combination of peak-COVID zeal then changed plans, I ended up with four of the A1050 Knockoff PCBs and parts to build them out. The design is a straight recreation of the A1050, the 256K RAM expansion for the (first) Amiga...

You are set up for success! (The AC connection truly is not a big deal to do— it’s the same three wires from the wall directly to the drive, but if you get to the point where you have DC and data sorted but are still feeling iffy on the AC, send me a DM, I can help you.)

There are certainly (vintage) external enclosures out there, though they usually already are home to a drive or two, and they are incredibly heavy and $$ beasts to ship around. (Here's an example of an enclosure that comes with 2x Shugarts.) If you don't have easy access to one of these, you can...

Totally. If you happen to use a Mac, the built-in Calculator app has an octal mode (first View->Programmer, and then move the slider under the "display" to "8". It also shows binary at the same time, so I find this super useful sometimes for octal and hex manipulation and conversions. When I...

Your splicing block looks good to me! I use a metal splicing block and splice tape from duplication.ca which carries good repair supplies for cassettes: https://www.duplication.ca/ (A nice thing about their splice block is that it will hold the tape securely in place in a channel to help you to...

It's basically like a KIM-1, but produced in parallel by another chip company (Synertek) that was second-sourcing the same computer CPU chip (the 6502) that Commodore built the KIM-1 around. (a quick blurb here ). KIMs and VIMs and SYMs -1 are all "computers," but distilled down to their...

Not to complicate your efforts further but you might consider eventually sending one of your tapes to someone with a functioning Teletype model 33 as a final cross check– those use an entirely mechanical reader as I understand it, so the spacing really would matter. Given their popularity in the...

Glad they made it intact! I’m also intrigued by the hole spacing— my punch is a high speed GNT model from the 80s (probably) or later and I expect it to be pretty precise. Its reader is optical but the tape feed is still done with a rotating mechanical sprocket so presumably it can read tapes...

I think this depends on the platform and software/firmware you were using to read/write the tape? The Altair 680 tapes that used the Motorola S-record format in ASCII used CRLF between lines, and used even-parity bits. I believe Pittman's Tiny BASIC program used only LF, no parity, and they...

Excellent! Great achievement, young Steve Dompier would surely approve.

I sense there may be a conceptual skew that happened somewhere up the thread and I worry that you're unintentionally overcomplicating it. I assume you're looking at Dompier's original listing at the bottom of the linked page because we're talking in octal. That listing is already set up to do...

What Chuck said ^^. Octal is a holdover from earlier systems where different bit widths were common, was benign but confusing on the 8-bit Altair, and very quickly was replaced by standard hex on the IMSAI and the Altair 680. If you have a 6-bit character, you can represent that fully and...

I second everything Dave said (and I add my own editorialization that octal is wildly unintuitive for anyone who learned software development after the 70s, for whom multiples of 8 bits is simply a law of nature) but yes, 041 is an octal value, and one way of recognizing that on the Altair is...