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MicroMac, a Macintosh for under £5

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Re: MicroMac, a Macintosh for under £5

#161

Post by habi »

phone8675309 wrote: post #160
habi wrote: post #116

Earlier quoted context omitted.

CRTs were emitting an electron beam to draw images on a phosphorescent screen, not emitting X-rays: https://en.wikipedia.org/wiki/Cathode-ray_tube Blasting X-rays through a screen to the face of an observer would not have been a good idea…

Ask the Therac-25 patients if the difference between electron beans and X-rays is important

The difference is important in the case of a CRT screen, and less important in the case of cancer treatment with Therac-25.

CRTs produce a (low-intensity) electron beam that has just high enough energy for exciting the phosphorous screen.

Therac-25 was able to produce both a high-intensity electron beam or an X-ray beam, depending on the therapy need.

Re: MicroMac, a Macintosh for under £5

#162

Post by habi »

jlokier wrote: post #159
habi wrote: post #116

Earlier quoted context omitted.

CRTs were emitting an electron beam to draw images on a phosphorescent screen, not emitting X-rays: https://en.wikipedia.org/wiki/Cathode-ray_tube Blasting X-rays through a screen to the face of an observer would not have been a good idea…

X-rays are mentioned 28 times in the Wikipedia link about CRTs, https://en.wikipedia.org/wiki/Cathode-ray_tube Although X-rays are not used to draw the image, they are generated as an unwanted side effect. The phosphorescent screen emits X-rays when struck by the electron beam. To protect the user, the glass must be a special kind of glass to absorb those X-rays, and the accelerator voltage has to be set not too high…

> X-rays are mentioned 28 times in the Wikipedia link about CRTs, https://en.wikipedia.org/wiki/Cathode-ray_tube

CTRL-F for "X-ray" gives me 1 result, "-ray" gives me 13 results ;)

Absolutely agree that X-Rays are generated in the phosphorent screen, but they are not emitted by the CRT.

> […] and the accelerator voltage has to be set not too high.

Yes, with electrons only so high that they reach the screen, which is low enough to only generate very minor secondary X-rays in the screen, which is then nicely shielded. If the phosphorous screen would be blasted with X-rays, the shielding of the screen would need to be much thicker and expensive.

(I’m working with shielded microCT machines, so speaking with a bit of experience)

Re: MicroMac, a Macintosh for under £5

#163

Post by tomcam »

rnewme wrote: post #139
tomcam wrote: post #51

Earlier quoted context omitted.

We need to deal with some important issues you raised. > After the date... She quickly learned I'm no stranger to dumpster adventures. Ah, was there another date? > Recently, I was renovating something with my wife Any relationship to dumpster adventuress?

There were more dates, including illegal aquirement of shopping cart on her side for me (she drove it in public transport across half of the city during night), stop sign from me to her (new, unpacked, found on a construction site, NOT removed from street!) and broken fire extinguisher from her again (saw a pile behind a local stadium and somehow got through the fence). My wife is not the same lady, she prefers store…

Ok that was a fun answer, thank you!

I don’t mean to boast but I’m kind of a big deal—I was able to get 3 shopping carts off the free section of Craigslist when a local food bank discarded them. One awesome part about living here in the Seattle suburbs is excellent free stuff that doesn’t even require larceny to obtain.

My wife is tolerant of these activities too but prefers I stay out of dumpsters. How dare she ;)

Re: MicroMac, a Macintosh for under £5

#164

Post by MenhirMike »

snvzz wrote: post #149
jamesy0ung wrote: post #63

Earlier quoted context omitted.

A500 Mini isn't as cool IMO. It's just a generic arm board running linux with an Amiga emulator. The keys don't even work. May as well just use a Pi or a PC.

Indeed. It's just a cash-grab device exploiting nostalgia. The software it uses, amiberry, is open source and was made for the more powerful, useful and common Raspberry Pi boards. Getting one of these is a much better idea.

I wouldn't go _that_ far because the case, mouse, and controller are actually really good quality. But yeah, the bundled games are a bit underwhelming and ultimately it's just a Linux/Emulator box.

I wish someone would make an Amiga shell for a Raspberry Pi that's quality like that. I can 3D print my own, but injection molded plastic is still a quality level above.

Re: MicroMac, a Macintosh for under £5

#165

Post by MenhirMike »

hammyhavoc wrote: post #9
MenhirMike wrote: post #6

I was considering doing something like that for an Amiga, running AmigaOS 3.2. It's a cute idea, especially once you 3D print a shell that looks like the original (shrunken down). I do think that the lack of an old school floppy drive means that something is kinda missing from the experience, but I do like the idea of having a machine dedicated to running this instead of just firing up an emulator on my existing desk…

Need CRT too for the authentic experience.

With a 4K display and HDR, we can actually do really decent CRT emulation. It seems a bit ridiculous to need 4K/HDR to emulate 40 year old display tech, but you need the resolution to do the aperture grille in a way that's small enough to work, and you need HDR for that phosphor glow.

The Retrotink 4K has been pretty eye opening (and eye-watering, given the $750 price tag) in terms of where we are with CRT emulation these days.

Re: MicroMac, a Macintosh for under £5

#166

Post by numpad0 »

rbanffy wrote: post #129
hammyhavoc wrote: post #121

Earlier quoted context omitted.

Interestingly, a lot of folks used to repeat the x-ray thing, that's where the term "eyeball cancer machine" came from.

Well... Technically we spent a lot of time looking down the barrel of a particle accelerator...

Adding to my own shame, TIL not all free-flying electrons are X-ray

Re: MicroMac, a Macintosh for under £5

#167

Post by tuatoru »

ssl-3 wrote: post #125
tivert wrote: post #101

Earlier quoted context omitted.

>> Over a decade later, the fob got destroyed in an unfortunate boating incident. > Need to hear this story as well. I bet it's "dropped her keys into the lake." Perhaps after awkwardly balancing them a place that, in hindsight, should not have been used.

Nyet, comrade. She was at the front like some sort of living maidenhead while I leisurely rowed at the back with the entrenching tool that I kept in the car, one evening at an outdoor music festival somewhere in the Midwest. It was all very beautiful; the girl was beautiful, the sky was beautiful, the music was beautiful, and the place itself was beautiful; everything was approximately perfect. There was such a profo…

* figurehead (A maidenhead is quite a different thing.)

Re: MicroMac, a Macintosh for under £5

#168

Post by vectorcrumb »

dougg3 wrote: post #25

This is a really impressive project! It was a fun read. Thanks for sharing! I like this writing style. > As an aside, I try to create a dual-target build for all my embedded projects, with a native host build for rapid prototyping/debugging I find myself doing the same thing on my embedded projects, including at my job. I actually find myself using the PC build much more frequently than the hardware for my day-to-day…

How would you go about setting this up? Do you mock out low level calls or are you running some sort of emulator?

Re: MicroMac, a Macintosh for under £5

#169

Post by hammyhavoc »

rbanffy wrote: post #129
hammyhavoc wrote: post #121

Earlier quoted context omitted.

Interestingly, a lot of folks used to repeat the x-ray thing, that's where the term "eyeball cancer machine" came from.

Well... Technically we spent a lot of time looking down the barrel of a particle accelerator...

I still do! Love my Sony CRT PVM. I bask in its glorious glow like a serpent in the sun.
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