Tomorrow morning a beautiful trio of two planets and the Moon will rise in the dawn. Venus will rise first at 5:02HST, followed shortly thereafter by the Moon and Mercury nearly together. The trio will form a neat triangle about 6° across. The planets will rise an hour before the light of dawn spreads across the sky and nearly two hours before sunrise.
What is modern? What is traditional? What is different about these two words and what they mean? Is there any real difference? I would argue that there is not and never has been any real difference, except in the minds of those who want to see it. A sort of golden age idealism, that somehow things were better back whenever.Too many seem to think there is some massive disconnect between the traditional and modern. They make an artificial distinction between our modern way of life, our current way of doing things and the ancient traditional way of living. Those who take a better look at the past know this to be false.
We are human, ancient humans were far more modern than many seem to envision. Many think of the past and see some cartoon version of people who are somehow less than we are today. A view of the past created by so many movies, so many bad historical melodramas.
If one were able to stroll down a street in ancient Rome you would see a city every bit as complex as a modern metropolis. All of the people you would meet completely recognizable in their roles. No cars or electric lights, but there are police and politicians, barbers and butchers, a world quite similar to our own.
We have a lot of fun when the kids come to visit. We regularly offer tours of Keck to local school groups. When they come we lay in a schedule of activities… Solar telescopes, an IR camera demonstration, tours of our remote operations, the activities can vary depending on the grade level.
After the last tour we got a packet of thank you letters from one of the classes. These are just fun to read, it is great to see what the kids remember from their visit. A drawing of telescopes set up in the lawn caught my eye, I was responsible for running the solar telescope activity!
The New York Public Library has just published 187 thousand digital images online. The collection is staggering in its volume, a collection of images that ranges across the spectrum of American and even world history. One could publish an interesting blog simply mining this huge collection for the historical tidbits it contains. World events to restaurant menus, there is just so much there.I did a few quick searches for interesting Hawaiian images. Most of the images showing the islands are either postcards or stereoscopic pairs. There are views of typical tourist scenes such as Diamond Head and surfing at Waikiki. There are quite a few images of the plantation era, sugar mills and such, as well as quite a few simple “pastoral” images with little context or interest.
In addition to the images there is a great deal of other material. Old engravings and illustrations, maps, even menus from restaurants dating back a century. I will have to refer to this collection when looking for illustrations in the future, there is a treasure trove of material here.
Most of the interesting images I found were stereoscopic pairs. Stereoscopic pairs were incredibly popular in the late 19th and early 20th centuries. While many might be familiar with the View-Master style stereo viewers of the 1950’s and 1970’s, the original version of this used a side-by-side print in place of a transparency.
But then there is this circuit board assembly I cam across… At first glance it looks like a wire wrap board. But there are no posts, the wires are flush to the board. Neither is it traditional point-to-point wiring, the wires are not terminated to solder pads beside the pins being connected. I had never seen a construction technique like this.
The board is an old PCB assembly found in a storage cabinet while clearing out the old junk that has accumulated about the observatory. No idea where it came from or what it was used for, the only clue is some writing on the box… “Keck level shifter”, Perhaps a piece of a detector controller? Someone clearly put a lot of work into the board at one time, now it sits in my office as unknown junk. It is the odd construction technique that caught my eye and led me to hang on to the board, at least temporarily. What is this?
A closer look under a microscope shows a connection clearly made by some sort of spot welder. There is a neat little hole through the insulation at each connection. Stripping back the insulation reveals a very neatly welded wire. Each wire is welded to the flat bottom of each pin socket. Every component pin is socketed, this includes all passives, which are mounted to headers and plugged in alongside the IC’s.
There are a number of advantages to this wiring method… The connections should be very reliable and robust, the weld is a nearly ideal electrical connection. As no connection pads are needed beside each socket the density is much higher using less circuit board real estate per component, you can cram more on the board. Interestingly the connection technique can be used without terminating the wire, daisy chaining to the next connection point.
There are disadvantages as well… The method clearly requires some sort of welding equipment with perhaps an automatic wire feeder and cutter, a built-in microscope for positioning the weld, and more. Clearly an expensive piece of kit. No components can be present during welding as they may suffer damage from the high electrical currents needed for spot welding, thus everything must be socketed. All those little sockets are expensive! Rework or repair would need to be done with more traditional soldering techniques.
I would love to see the machine that did this board assembly. Maybe even a chance to use it. More information on the process seems difficult to find on the web without a trade name or other keyword that would clearly identify the process.
Not that these welded wires would be of much use today. The technique is clearly ideal for complex digital circuits of the style and speed that was common through the 1980’s to around 2000 or so. After that the prevalence of surface mount technology and the abandonment of the DIP package would doom the method. Modern high speed circuits benefit greatly from the more controlled traces of a printed circuit board and would not fare well on a welded wire board. In these days of easy computer layout and cheap printed circuit boards welding would not be my fabrication method of choice.
My slide digitizing project is now producing data by the gigabyte. As expected I am filling up the drives on my desktop computer. Not that there was a lot of space available in the first place, less than 50Gb was clear on the primary data drive. Time to buy a new hard drive! At least when I built the computer I bought a gaming cabinet with plenty of drive bays.I face the agonizing decision… When dealing with critical data, what brand and model of hard drive do I buy? I make multiple copies, but still, a failure can cost me days of work between backups. What hard drive do I buy for my photos?
The reviews on Amazon and other retailers are nearly useless on hard drives. There will always be failures of devices like this, and angry buyers are very likely to leave negative reviews. Thus the data looks very skewed and it is hard to evaluate the reliability in any sort on meaningful way. Much less compare one drive to another.
There is real data! The cloud storage provider BackBlaze runs thousands upon thousands of hard drives. Obviously hard drive failure rates are of paramount importance to them and they closely track each type of drive they buy. Fortunately for the rest of us they publish this data and allow us to see what does, and does not work.
There are several obvious lessons in the data… Stay away from the 3Tb drive from Seagate and to a lesser extent the 3Tb drives from Western Digital. Several 4Tb models appear to be far more reliable. The failure rates on the worst drives can be upwards of 20% to 30% per year, while the better drives well under 5%. Those rates may seem high, you need to consider the hard use these drives get in a data center.
Based on this I have a new HGST 4Tb drive installed in my computer. All looks good so far, a trouble free installation and my photo collection copied over without issue. Now to see how long the drive lasts when I put some hours on it.
The Moon and Jupiter will rise together this evening of January 26th. The Moon will rise first, around 20:40HST, followed by Jupiter half an hour later at 21:25HST. Over the course of the night the Moon will slowly approach Jupiter, closing to about 4° by dawn.
The following evening, January 27th, the order will be reversed, with Jupiter rising first at 21:21HST and the Moon rising twenty minutes later at 21:40HST, with about the same separation of 4°.