I'd like to call attention to the EEVblog.com forum.

I was put off by Dave's YouTube persona and didn't pay attention to it for a long time. Yes, there is no shortage of Bozos, but it is the damndest collection of PhDs, both papered and common-law I've ever come across on line.

Obviously, anyone with a user name including "Dr" or Wizard" is almost certainly full of BS. But I have verified a number of times by PM that the person did indeed have a PhD, though generally not in EE.

Probably my favorite example was a post entitled, "Has Anyone Built a Mass Spectrometer". The OP is working on a quadrapole mass spec. About the 4th post in was someone who had built two. The first an academic instrument. The second a commercial instrument with a $750K budget.

But there are many more people playing around at that level. So it's a lot of fun. At least if you like hanging out with people who know more than you do. And helping others trying to get there.

There's an amazing thread on building a picoradian tiltmeter using a $12 Chinese vial and a capacitance sensor. Though a slightly more expensive British vial gives better performance because the interior finish on the $12 vials is not very good. These are instruments which placed on a concrete slab have a strong response to walking near it. And register clearly that a car pulled in or out of the driveway from inside the garage.

This will not be long, but I'll make a brief comment on my reasoning.

If you look back to the bronze age, that was only possible because there were high tenor (high metal content) ores close to the surface which could be readily mined. And there were abundant trees with which to make charcoal to smelt the ores. Neither of those still exist. The natural resources left whether minerals or fossil fuels are difficult to reach and in the case of metals, *very* low tenor. It takes tens of thousands of people to get a single drop of oil in 9000 ft of water at 30,000 ft BSL. I worked a little bit on St Malo, a Unocal discovery before Chevron bought them. I was riding home on the bus and chatting with a Brit who was subsea systems manager for Jack, a nearby Chevron discovery. All he was responsible for was the equipment that sits on the sea floor and ties in to the production system. He had a $2 billion dollar budget. This was in 2006 or 2007 Jack, St Malo and another field produced first oil in2014. They were discovered in 2003 and 2004. The FSPO (floating storage, production and offloading) system cost $7.5 billion dollars.

How many welders, machinists, fitters and other skilled tradesmen do you think it takes to spend that much money? This was 10 years of intense hard work by a vast number of people. My wild guess is that there were probably about 50-60,000 people involved at some point. Maybe only a few hours like me. All I did was do some synthetic seismograms for the well tie.

If the trucks stop delivering food for a week, there will never be food on the shelves again. Almost everyone has less than a week's supply of food. So it they can get it, they'll stock up as much as possible. In the context of a "just in time" inventory management environment there is *no* capacity for increasing the supply if demand increases. And if demand increases because of a shortage of truck drivers because most of them are sick or dead from influenza, or there has been a Carrington even, a high altitude nuke detonated above the US, a Crater Lake or Yellowstone level caldera collapse or any of a *very* long list of events I can recite., there will be even less capacity to supply food. My doctor, whom I've known since we were 10, tells me people can survive without food for about 60 days.

The net result i will be a period of 30-60 days of incredible violence during which 90% or more of the population will perish. The survivors will be scared and isolated. So social organization will be very difficult.

The Hollywood "Mad Max" version of this is ludicrous. Look at thew costumes. Clothing laced together with leather strips through metal eyelets? Where in the hell are they going to get eyelets? There are no refineries at well sites. There is very little oil left that is not 1000's of ft down. What is left is in places like remote parts of Mynamar.

There was a great article in the Oil and Gas Journal about 15-20 years ago about oil production in the interior. The wells are drilled by setting up a tripod with a pulley. A length of pipe with a beveled edge is attached to a rope. The length of pipe is raised and dropped until it fills with dirt. It is then hauled to the surface, the dirt removed and they start over. Periodically they drop plastic bags off water down the hole as they have found it increases the penetration rate. Once they reach the target, the oil is brought up using a bailer such as the well bucket a childhood friend used to draw water in the 60's.

From there it is transported by young women in 5 gallon jugs to the refinery which consists of a still made from 55 gallon drums.

The wells go dry pretty quickly, so they move over a few feet and rill another one. They even do this "offshore" in a lake using bamboo platforms.

They are very resourceful people, but they are not going to be making semiconductors or machine tools anytime soon unless someone provides a lot of assistance. But those are the only people who have *any* readily recoverable resources. They will survive a collapse of civilization far better than the rest of us. But they will also have no access to the knowledge that makes modern technology possible.

"Oh, but we can use scrap." Oh, yeah? And how many years before all the cars, trucks and other pieces of iron an steel are just brown spots on the ground? Far too low a tenor to be recoverable. A few metals such as gold don't oxidize, but most do. And all the metals important to technology do. Iron is extremely abundant and cast iron is just amazing. It's almost an argument for creationism it's so amenable to primitive methods. But if you don't have high tenor ore, you cannot dig up and smelt an ounce of it. Too much digging and too much tree cutting required.

I got interested in DIY technology around age 20. So at 65, I have spent 45 years trying to prepare for such things. But after reading all those books on the history of technology it sank in that there were two problems: social organization at a large scale (how may people did it take to build the pyramids) and resources which were accessible to technology such as used in Mynamar. Which is only slightly more refined than Drake used in 1859.

I have the tools to do *almost* everything and a library to tell you how. But I'm 65 and have glaucoma. So I'm in a race between dying and going blind. Both my parents lived into their 90's. I hope I do not. I can play guitar and harmonica rather well. Good enough that I can walk on stage and rip a tune with a band I've never played with. But I don't relish the idea of being "Blind Boy Rufus" (I was born with red hair and was given the nickname by my dad. I dropped when I graduated college with my BA in English lit).

I came to realize a few years ago that I am a modern day Noah. I have built an Ark to carry technology. But I have no children and most of the under 30 population considers books as door stops.

So, Toby, that's a short version of why I abandoned the project. It's a very gloomy future. And after 65 years of learning everything (except biological sciences) that I could I can offer no solution. The Silicon Valley elite imagine that when the collapse comes they and their family will get in their personal jet and fly away. Which is possible if they can fly the plane themselves. But the pilot is more likely to shoot the owner and family and take his family than take theirs and leave his own behind.

This is a wretched platform for writing. Doubtless there are many things in my writing which would make me cringe. I took a degree in literature because I wanted a good liberal arts education. The sole criticism I should make of it today is I should have taken math at least up to ordinary differential equations. I did do that later and a *lot* more.

Kids in high school don't learn algebra, geometry and trigonometry because their teachers don't know anything about applying it. But every good skilled tradesman uses them *every* day. And then are insulted because they didn't go to college. It's hard to be motivated to learn something which is difficult if you don't have a clue why you are doing it and neither does the teacher.

I'm going to end it here. Thank you Toby for asking. I hope that at least a few of you found it worthwhile reading.

Reg

On 11/22/2018 4:03 PM, Mike Feher wrote:

Hi Guys –
My question is what do I do with all my engineering college texts both undergrad and grad type. They are mainly from the ‘60s and I believe relatively worthless now. I cannot stand to throw them away. Ideas appreciated. – Mike

Hello, Mike--

I volunteer at a local book sale as the sorter/pricer for science and technology
books. We typically reject almost all texts, especially older editions and those which have been stricken by the Mad Highlighter (*). Recent editions may
get shipped to a used-book wholesaler. Professors may specify that their
students use the prof's own text, for which he or she may receive royalties from the publisher-- hence, older editions are no longer welcome and the poor students are out $100 per text or more.

For our book sale, I'm free to accept books that I deem saleable or of classic interest (e.g., Terman, Rad Lab, ARRL Handbooks) and I price them inexpensively.

The next possible outlet is your local public library, which may have a free-to-take cart.
Some libraries charge a small amount for discarded or donated books and
may accept your gift books. Local libraries may welcome donations of books
that are in good condition for their fundraising sales.

Last stop is your local secondhand shop. But based on what I've seen at Goodwill and Salvation Army stores, most of what gets donated are romance novels... (&)

73--

Brad AA1IP

(*) The Mad Highlighter typically approaches a textbook with yellow marker in hand and
and begins highlighting every other sentence (regardless of content) on page one.

Twenty or so pages into the book, the highlighting thins out, and thirty pages in stops altogether.. At that point, it's safe to assume that the luckless book owner has dropped
the course....

(&) "Oh, Harold!" she breathed, as he frantically fumbled with the restraining fasteners
on her GPIB harness connectors.... [From "Fifty Shades of Gray Pixels"]

On Nov 22, 2018, at 11:58 AM, Jeff Kruth via Groups.Io <kmec@...> wrote:
Hi Paul!
Look them up, there are 28 volumes. They are GREAT! I finally bought a complete set in great condition for 100.00 off a museum

Paul,

Thanks for your comments on the Rad Lab and its work.

The introduction to (at least) one volume tells that “After the cessation of hostilities, many of the scientists and staff “agreed to stay on to document the work” and did so in about 6 to 12 months!

In one set of books, we gave to the world the secrets of how to build a radar! The Magic of Microwaves explained!!

It seems to me that much of the content would have been classified, especially during the war. I wonder if there was a wholesale classification-release program in effect.

...You can look at Hewlett Packard waveguide instrumentation from the 1950-1990 time frame and see that it is directly derived from the Rad Lad designs with HP niceties added!

This phenomenon is parallel to the amateur radio gadgets offered commercially that were taken quite directly from the RCA Hints

and GE Ham News

publications. Two examples are the Millan 92101 receiver preamplifier and the B&W LPA-1 linear.

In a related happening (briefly), General Radio mostly avoided making military-specific equipment. One exception perhaps is the APR-1 and APR-4 ECM receivers. They were developed from a GR instrument meant as a detector/receiver for VHF/UHF/Microwave work, the P-540 receiver. See GR Experimenter March 1947 for further information.

Direct link:

At least go to the KO4BB website and download the PDF’s.

I should download the whole lot as a project. After all, my computer local backup external disk holds TWO TERABYTES, and cost about $80.00. (It is partitioned into 4 separate drives for such purposes.)

My personal connection to the Rad Lab was that my EE professor at Tufts (1964-’66) was Prof. Hammond. He’d been at the Rad Lab, and referred to MIT as “Tech”. I have to wonder if he contributed to the books and what he worked on there.

Here were guys figuring out how to make all the stuff we use now, and EXPLAINING IT.

Indeed: schematics, tube types, resistor and capacitor values (some pulse transformers are mysterious), and so on.

My favorite volume is “Vacuum Tube Amplifiers” by Valley and Wallman. I have two examples of tube type IF amplifiers I assume are radar IF strips. The design and implementation of these things are covered in this volume: the technology used to achieve wide bandwidth with proper phase charcteristics involves stagger tuned stages, specific tuned circuit Q values set with parallel resistances and more.

I didnt even mention the books on timing, waveforms, vacuum tube circuits, servomechanisms, radomes, so on and so on.

Analysis and design of servo systems is a faint memory now, perhaps that is just as well!


Long live this fundamental archive of good stuff, and may our interest in it survive long.

Roy

Roy Morgan
K1LKY since 1958
k1lky68@...

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may be this news can help F1CHF ? ? ? ? ? -------Message original------- ? De : Harke Smits via Groups.Io Date : 22/11/2018 17:34:46 A : [email protected] Sujet : Re: 50 ohm thermocouples was RE: [HP-Agilent-Keysight-equipment] 478A power sensor recal for HP meters (was diode mounts) ? Thanks Jeff! Nice read. Best 73 de Harke On Thursday, November 22, 2018, 5:30:52 PM GMT+1, Jeff Kruth via Groups.Io <kmec@...> wrote: The screws are weird!? Back in the late '70's when a 478A head was worth $250 working (real money then!), I used to repair these. I ran a lab at Westinghouse Defense in Baltimore that did MIC work, microwave micro-assembly and wire & ribbon bonding. I used to pay the technicians on their lunch hours to mount salvaged thermistor beads for me. If you blow out a 478A with too much RF, the reference pair is still good. I used to salvage these and match them to the Ref pair in another head, replacing the blown RF pair.? Made a bit of cash that way! The screws do NOT contact anything, instead they "approach" the thermistor beads, being aligned directly above them. My take on it is that they change the ambient temperature environment by adding a small bit of "hotter" metal closer to the bead, sort of like the DC offset adjustment on an op-amp. However, I could be wrong: instead of adding heat, they may change the reactance of the bead to the chopper frequency, but this seems less likely, as the size is so small (not much capacitance and the frequency of the chopper is low (IIRC, about 10 KHz). The general failure in adjustment in an attempt to re-calibrate the head is to insert the screw a little too far so that it hits the bead and snaps a wire lead off it. Hi Paul!? I found that the "driftiness" of the head can sometimes be improved by working the re-balance adjusting the screw pair alternatively, back and forth. 1/8 turn out on one, 1/8 turn in on the other, etc.? YMMV. I used to leave the head shell off and hold the mount in my hand to heat it, release and watch the behavior of the re-compensated mount as it settles back to ambient. I could get them pretty good after a while.? Oh well, all that was a really long time ago now, it seems, in a period when I had more time than money, now the other is true. Found a box the other day of a pile of 478 & 8478 guts, left over bits from these days, some beads missing. Off to gold scrap, I guess! 73 J. Kruth Hi Jeff?? good to talk to you again regarding the 478 and rebalancing the head using the screws I have found that the temperature? compensation isn’t as good after you have to rebalance using the screws ? By the way never opened the 478? to find out how the screws work Paul B In a message dated 11/22/2018 11:01:39 AM Eastern Standard Time, yrrah53@... writes: Interesting point. I have not worked with thermistor heads since ages but I always wondered how the screws work on the HP478 and HP8478? 73 de Harke On Thursday, November 22, 2018, 4:58:38 PM GMT+1, Paul Bicknell <paul@...> wrote: Hi Jeff?? good to talk to you again regarding the 478 and rebalancing the head using the screws I have found that the temperature? compensation isn’t as good after you have to rebalance using the screws ? By the way never opened the 478? to find out how the screws work Paul B ?

On Nov 22, 2018, at 10:39 AM, saipan59 <saipan1959@...> wrote:

...
I also have several of the original RadLab books. The one titled "Waveforms" is like a foundation text on pulse circuits and such.

I had hoped to get to the shed where the few Rad Lab books I have are resting in a box (it is now about +15 F here, and I am IN for the night after settling the sheep in the barn.)

So maybe tomorrow I’ll go look. If the Waveforms one is there, I’ll bring it in for warming and reading. I have on hand a package of laundry dryer sheets that may eliminate any storage aroma.

Roy

Roy Morgan
K1LKY since 1958
k1lky68@...

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On 2018-11-22 1:42 PM, Reginald Beardsley via Groups.Io wrote:

Jeff,
...
I have bought *every* book on the history of technology above high school level I have ever come across.

A few years ago I decided to read them all as preparation for writing a long essay or book pointing out why the "Doomsday Prepper" crowd is seriously deluded. I only read at about 400 now. Old age and 6 eye surgeries have taken a toll. I spent 6-8 weeks doing very little other than reading all day. At the end I concluded that there was no point. We are living through the Bible story of the Tower of Babel. And to make matters worse, *any* disruption in the supply chain such that there is no food on the shelves in the stores for a week and civilization will end. I am by training a geoscientist. All of the natural resources which can be exploited by a few thousand people are long gone. So restarting technology is not likely despite my having spent my entire life trying to master all the things that would require. I could see no point in pointing out a problem which cannot be solved.

Perhaps I am not the only one who would still like to read your essay on
this.

--Toby

Reg

Jeff,

So nice of you to merge the Rad Lab with yet another topic. Perhaps you could manage to learn to reply to the appropriate thread?

As for your 2nd paragraph. WTF? Loomis had a bunch of test gear disguised as a laundry truck for his MW tests at Tuxedo Park. Yes, he was extremely rich and powerful. But he also was sufficiently well educated to keep company on an equal footing with the absolute elite of science. That he was very modest and generally declined to take any credit for work even though he directed and paid for it is greatly to his credit.

I made a somewhat different interpretation with regard to the cyclotron, that they could not meet the physical requirements because of the increase in size. This was after all, a part of the Manhattan project. If they needed copper, they were going to get it. Although, IIRC, in the end they used silver. I think it's important to bear in mind that Loomis had a rather more far ranging view of the war effort than one project. I am quite certain cost was *not* a concern to Loomis. His concern would have been the demand for copper and the available supply. So I took the comments by Alvarez to indicate that the needed flux densities could be achieved within the design constraints if aluminum wire were used.

I can't find my copy of "Tuxedo Park" but the Rad Lab closed at the end of the war. And the explanation I recall from "Tuxedo Park" was as I stated. The correctness of Loomis' view is reinforced by personal conversations with someone I know who administered $4 billion in NFS grants for a number of years.

But, I'm really far more interested in other accounts of Loomis and/or the Rad Lab. Rather than devote so much attention to correcting my perceived failings, how about providing the bibliographic references I requested?

If you cannot furnish additional bibliographical references to the Rad Lab and Loomis, how about technology and manufacturing since 1800?

I have bought *every* book on the history of technology above high school level I have ever come across.

A few years ago I decided to read them all as preparation for writing a long essay or book pointing out why the "Doomsday Prepper" crowd is seriously deluded. I only read at about 400 now. Old age and 6 eye surgeries have taken a toll. I spent 6-8 weeks doing very little other than reading all day. At the end I concluded that there was no point. We are living through the Bible story of the Tower of Babel. And to make matters worse, *any* disruption in the supply chain such that there is no food on the shelves in the stores for a week and civilization will end. I am by training a geoscientist. All of the natural resources which can be exploited by a few thousand people are long gone. So restarting technology is not likely despite my having spent my entire life trying to master all the things that would require. I could see no point in pointing out a problem which cannot be solved.

Reg

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You can download good scans of the entire MIT Rad Lab series for free at:

They are full of useful information, but there is something to be said of holding a 65+ year old paper book in your hand.?

I'd? love to own the entire set some day.

Dave

Sorry if anyone was confused. The Rad Lab existed at MIT. My point was that Loomis was doing major work at Tuxedo Park long before he was put in charge of the Rad Lab. Given the high quality of the work Loomis was doing on his own nickel and the fact that he ran the Rad Lab, I don't think it is wrong to regard the Rad Lab as a change in location and a much larger staff. After all, the planning for the creation of the Rad Lab was done at Tuxedo Park in December of 1940.

As you claim expertise in the matter, can you provide or link to a bibliography pertaining to either Loomis or the Rad Lab? I have "The Invention that Changed the World" and one on Loomis, but would love to read more. I couldn't locate the biography of Loomis I have. There is a downside to having a 5000 volume library.

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