James boosted

Progress on the Feather Op Amp Lab: a (low speed) analog waveform display! Same comparator circuit from last week, but now in addition to visualizing the output on an oscilloscope, we can display it on the OLED. Here we see a 1 Hz sine wave from the DAC on OA0's output pin. Then we move to channel 1 to see the square wave, which is the comparator's output. Finally, we can see how adjusting the ratio of the resistors in the ladder affects the duty cycle — both on the scope, and on the Feather!

@polpo I am not super familiar with how the converters work. But I know CCFLs take 10s to 100s of volts to work.

So if you're only seeing ~1 volt AC, either the switching frequency is much higher than your DMM can read, it isn't the hot side, or I'm misunderstanding how the backlight works.

Good chance it's the last one.

@polpo You sure you aren't measuring the (pulsed) DC side? Because that's at least one or two orders of magnitude too low for CCFL

@paulrickards Ouch! I feel your pain.

Once, a seller emailed me proudly, saying they used several inches of bubble wrap. And they did on the top.

After removing 4-5 inches of bubble wrap, I got to the computer, sitting on the back of the monitor. The monitor had a single layer of bubble wrap.

Oh. Its glass screen was facing down. But at least they set it on another single layer of bubble wrap!

I don't think people understand how gravity works.

James boosted

After watching this video I feel like foraging for pine resin to make soldering flux! youtu.be/1piQpi00d-A

James boosted

I really liked the juxtaposition of fleece fabric with 3D printed meshes from my rainbow fish project printed, so I'm now working on making a soft-sided icosahedron with a grid of 3D printed triangles on each side (to be illuminated ofc) It's required a LOT of hand sewing to securely attach the 3D printed meshes to the soft icosahedron sides, but there are now only two left to go before I can start installing the LEDs.

James boosted

I'm most excited about the light/siren combo.

I plan to remove BT/Audio circuit from an old speaker and adapt it to the siren/horn.

Then maybe VU-sensitive lights? Or just something that turns on via internet stuff?

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Here are some of the things I picked up last weekend at Hamvention ... These will become parts of future projects. (Really! ... probably.)


James boosted

Total Replay v5.0 is out. It features 484 Apple II games (182 new since v4), all playable from a single bootable 32MB hard disk image.


Code: github.com/a2-4am/4cade/releas

Thanks to @a2_qkumba, @txgx42, @helix_nrg, Andrew Roughan, Frank M., Kris Kennaway, @ladyailuros, and everyone else who contributed to this project in the past four years.

#AppleII #retrocomputing

James boosted

@oskay The cover reminds me of a "motivational" speaker I had to watch once (for a work function.)

He spent 15 minutes going on and on about having a strong self-discipline.

The problem was that his beer gut was the size of a keg.

Related, a typesetting book that looks like that is impossible to take seriously.

Also, this little guy was on a table near the entrance.

@48kRAM Did you find a replacement for the BAC?

I forgot to measure the physical size and location of the pins with the one in my SE.

A few pictures from CoCo Fest 2023 in Carol Stream, IL. (Very close to Chicago)


@48kRAM Well that's a bummer!

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