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Comment Re: The 555 timer sucks. (Score 1) 170

I agree that the 555 is not very good, but I LOVE knobs! Knobs are like 5,000,000 times more pleasant than buttons. I just put four potentiometers on my Burning Man art lighting project built on an Arduino shield, so that we can control the mood by changing the parameters a bit.

Comment Re:Capitalism is killing them (Score 5, Insightful) 182

The progressives are responsible for making our air clean. The big cities in America used to look like China is now, but the EPA was created to do something about it, and has succeeded admirably. People rag about the government overreaching, but this is one shining example of the government solving a big problem. Unfortunately, the EPA has been hamstrung by the conservative Congress, which seems to think that keeping our air from becoming all polluted again is too much of a price for industry to pay. Assholes.

Comment Re:Needless limiting of options (Score 1) 170

Analog computers weren't built of TIP120s or LM386s or 2N2222s. They were built with 12AX7s and 5U4Gs, and the later ones of Philbrick K2-Ws. By the time the TIP120 came out, DEC was building PDP-11s out of TTL chips. TTL is rather dumb nowadays, as we have CMOS.

One thing is true about the old parts, though... you can still buy them. I've had occasion to work on some 15 year old electronics, and none of the bigger chips are made any longer. We can still get 741s to fix our 40 year old spectrometer, but no Xilinx 4003s to fix the 20 year old one, nor CoolRunner CPLDs to fix the ten year old one.

Comment We actually use them in our telescopes (Score 4, Informative) 170

The TIP120 is not too efficient, but if you're already going to be dropping a couple volts in the transistor, it simply doesn't matter. Our radio telescopes use very low resistance coils to control the attenuation of a microwave signal using a device called a ferrite modulator. Its voltage drop is about 1 volt, and the lowest power supply available is 5V, so it works fine. Plus, we have a bin with 50 of the darn things in the parts cabinet. So there, Tom! (I jest. He's one of my best friends.)

Comment Re:Been laid off twice, and gotten better jobs (Score 1) 179

I remember being laid off once, back in 1982, from a small local hardware manufacturer. Turns out that several of the principals were leaving to start another company, and they hired me immediately. I worked with them for 19 years, and after one of them left to go back to the university that we all came from, he set me up with a cushy job there.

It's definitely who you know. (It helped in the last one that I was able to waltz in and fix a system that had been stalled for a year, due to an unnoticed typo.)

Comment 40 year old spectrometer (Score 4, Interesting) 620

I work on the 12 meter radio telescope on Kitt Peak. It was built in the mid sixties, refitted with a new dish in 1982, and replaced last year with an ALMA prototype antenna. We still use the old filter bank spectrometers. They were built in 1973-4. This item.

Comment Converted old cell phone to uplink transmitter (Score 5, Interesting) 210

Many moons ago, I got tired of what was on the radio, and I built a pirate FM station. It had a studio supplied with over 50 volunteer DJs, but most of all it had the transmitter up in the mountains, with a UHF uplink system, to allow for very broad coverage of our city. I made the uplink transmitter form a 1985 Motorola cell phone, the old brick type. It was suitably modified to put out wideband FM audio. You might be able to read about it by Googling "Radio Limbo Tucson".

Comment Re:Nothing that money can't buy (Score 1) 65

I work on one of the telescopes that is on Mt. Graham. My father was an astronomer who did the initial site surveys for the Mt. Graham observatory and spent a good bit of time on Mauna Kea as well. He took his family to several observatories in Arizona and Mexico; I never thought of observatories as "desecrating the land". Rather, they are quiet places in which solemn work gets done to better understand our place in the universe.

My current boss's husband is the guy who made the special legislation happen that allowed the scopes to be built. He's proud of his underhanded accomplishment. I'm also friends with several Earth First!ers who were on the other side of this fight.

I think both sides on this war are assholes.

Comment Apple ][ was a great product (Score 4, Interesting) 74

I worked at a Byte Shop in 1978-9 as their repair department. I was in high school. We sold Apples, TRS-80s, S-100 bus stuff, etc. The Apple was the most impressive machine, by far. It was apparent just from looking inside it, that the design was the way of the future.

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