I’m still waiting on resolution for the capacitor issue, but I decided that I might as well build the cassette interface.
All sockets are in, so I’m to chapter 2, step 10 of the assembly guide – the installation of the seventeen 0.1 µF decoupling capacitors.
Here’s the problem: Unicorn shipped 1.0 µF caps. This matches the silkscreen on the PCB, but the Mimeo manual makes a point of mentioning that real Apple-1 computers used 0.1 µF instead. I could actually install the incorrect caps, and it’d probably be fine, but I’ll wait for Unicorn.
In any case, step 11 (installing the other six small caps) isn’t actually dependent on step 10, so I went ahead and did it. The next step is another power/ground short check, and while I could easily continue on (really, if I wanted to, all the way to initial power-up, because the decoupling caps aren’t a factor until I start stuffing chips in), I figure it’s best to stop here, so I don’t deviate too far from the manual (and then have more work to do to diagnose a fault if I do mess up).
That is all.
Update: Decided to start soldering. Finished chapter 2, steps through 5, of the Mimeo assembly and bring up guide (PDF).
Now that is all for today. Tomorrow’s plan: install twelve 16-pin sockets in row A, and we’ll see how I feel about doing row B’s fourteen 16-pin sockets. It’ll be a total of 42 sockets to finish chapter 2, step 6, although I’m definitely not doing all 42 sockets tomorrow.
Just thought I’d throw a quick post up… I’m going to be starting a Mimeo build very soon. (For those unfamiliar with the Mimeo, it is a (rather faithful) clone of the original Apple-1, Apple’s first computer. I got to use the real thing at KansasFest 2013, thanks to Chris from Chicago, and caught the bug.)
What all have I bought so far…
- Mimeo PCB, PROMs, and ACI replica from Mike Willegal – still waiting on that
- Panasonic RQ-2102 cassette recorder. I did find out that this is not the cassette recorder that Apple recommended in 1976 (it appears to have come out in 1994, in fact), contrary to what’s floating around, but it is one that apparently works quite well with the Apple Cassette Interface.
- Apple-1 parts kit from Unicorn Electronics – that shipped lightning fast, sitting on my kitchen table now, although I need to check the BOM against what shipped just to be safe
- Various odds and ends for the power section (mostly from Digikey) – well, I just ordered those, so except for the couple things I got locally today…
- Oak plywood to use as a base to mount all of this on – needs to be stained to look better, but I think it’ll be decent
What I still need to buy…
- Replacement encoder for the ][+ keyboard that I have – many years ago, I was given a ][+ that had been (even more years before that) converted into a (cheap) analog clock. Machine was gutted, hole drilled in the lid to install the clock guts. So, it’s a damaged case, and a keyboard – I don’t feel bad about taking the keyboard (the lid is the interesting bit anyway as far as this particular machine’s history goes). Unfortunately, when it was gutted, the encoder was taken. There’s a couple options I’ve got here – Vince Briel sells the Apple II Super Encoder, and Wendell Sander once did an Apple-1 specific encoder for the Apple II keyboard – I need to see if he still has any.
- Plexiglas cover. My ideas for the enclosure are extremely minimal – wood base, with everything mounted to it, some nice tall standoffs (about 4 inches), and a plexiglas cover.
- Plexiglas box around the power components. (Das 120-Volt-Komponenten sind nicht für gefingerpoken!) This will need to be laser cut, and will provide mounting for the fan (I don’t trust those power components to stay cool otherwise), power socket, and power switch.
- Vince Briel’s Slot 1 Expander (listed on the page for his Replica 1 (which is not a replica, but it is compatible with the Apple-1)) – not needed, but nice to have, and I’ve got a nice place for it in my planned case layout. And it makes some plans for Apple-1 shenanigans a little easier. 😉
- Maybe a CFFA1? But I don’t strictly need that…
I’ll be posting more status updates as I make progress along the path to owning a computer 1976-style.
I’m going to rant a bit about the availability and pricing of transportational cycling gear inside the US, because I’ve been inspired by recent purchases. Continue reading “A rant about transportational cycling gear in the US”
Prompted by a Hooniverse article on the subject, I thought I’d go ahead and tackle driver’s licensing in the US in a blog post. Continue reading “Thoughts on driver’s licensing standards in the US”
I’ve been busy upgrading my folding bike.
Starting point was a bone-stock 2002 Dahon Boardwalk 1.
Added the following:
- Skyway Tuff Pads (they appeared to be the Kool Stop salmon compound, and the LBS had them in stock, not sure that’s what they actually are, though)
- 1976 Sachs Duomatic 28h 2-speed kickback IGH coaster brake hub, built into a Sun CR18 rim by the LBS (gearing is 48/22)
- Planet Bike Superflash, turns out that it lines up perfectly under the sprung saddle
- TransIt Epic DX rack trunk
- Biologic Joule 2 20h dynamo hub (Biologic/Tern sells these prebuilt with Kinetix Comp rims for $115 shipped to the US)
- Tektro Sabre BX2 brake lever (the stock plastic lever was honestly terrifying)
- Busch & Müller Lumotec Lyt BN plus headlight (in German)
I think this is pretty much all this bike needs except for maybe tires and a pedal upgrade.
A couple weeks ago, I found the SwissMicros credit card-sized clones of the Hewlett-Packard Voyager series of programmable calculators, and decided to order one. Today, my calculator arrived, so it’s review time! (And, I apologize in advance for the crappy camera phone photos.) Continue reading “SwissMicros DM-15CC calculator review”
So, firearm regulation is a major topic here in the United States as of late, and is a political minefield.
Myself, I feel that additional regulation of the availability of firearms is required to maintain societal stability, but it can be done without banning any classes of firearm – no, not even “assault weapons”, although they’re not even the biggest problem.
I have some ideas for how firearm regulation could work in this country, while still allowing people to own firearms for personal defense, hunting, and other shooting sports. (Yes, I’m aware of the argument that the purpose of the 2nd Amendment is to allow armed insurrection. I’ll simply reply with this video.) Continue reading “My opinions on firearm regulation”