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Comment Re:I'm curious (Score 1) 97

Thanks for the information. I work on both of those telescopes in Arizona. The HHT has receivers covering 200 to 690 GHz. We just installed an ALMA prototype antenna on Kitt Peak, and have a grant to build a four-band receiver system for it that will cover 60 to 270 GHz. These are also used for VLBI interferometry, but that's another story.

Comment Re:I'm curious (Score 4, Informative) 97

I work on telescopes of the sort that were used to make these observations. In fact, I built the spectrometer that the cited author Stephanie Milam used to get her degrees in astronomy at Arizona. The spectrometer (these days) is a big FFT machine capable of resolving perhaps 1 GHz of bandwidth into 16,384 or so channels. The frequency received by the telescope is typically many GHz. The huge IRAM telescope works at lower frequencies than our smaller scopes in Arizona, which operate above 100 GHz. The spectral lines are first replicated in a vacuum chamber in a lab, to make sure that the spectral signature is thoroughly documented.

Comment Re:Ahmed's story doesn't hold up under scrutiny. (Score 1) 193

When I was a freshman in high school, I built an LED digital clock based on an app note in the back of the RCA COS/MOS data book, 1973 edition. It took a lot of wire wrapping, but I made it work. I mounted it in a nice wood-grained box from Radio Shack. It ran on batteries. I brought it to school one day, and got my electronics teacher to give me extra credit for it, and enjoyed showing it to kids on my 8 mile long school bus rides.

So I did about eighty times as much work as Ahmed did, and I STILL didn't invent anything.

Give the kid a break. At least he was doing something remotely original.

Comment Re:My view of this (Score 1) 662

As a fellow who built a wire-wrapped digital clock from a couple dozen CMOS chips when I was 15, I am keenly aware of the distinction. Yet it really has nothing to do with this story. I brought my clock to school also, but I didn't get in trouble for it. It had no alarm; it was in a metal box; I was white; it was 1976. Many differences. I think all of them are factors.

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.)

Adapt. Enjoy. Survive.