Sunday, April 05, 2020

What I Did Today

     Today and yesterday, in fact: I messed around setting up my ham station.  Having decided I need a 1:1 balun -- a kind of RF transformer, used to connect unbalanced (ground-referenced) equipment to a balanced device (like my G5RV antenna) -- I found a ferrite toroid core that seemed likely, wound two interwoven 12-turn coils of #14 house wire on it (as much as would fit), and looked around for an enclosure.

     I didn't have much, and then I found my collection of old tea canisters.  That worked.


     The coil is sandwiched between two 1/8" Garolite* plates held by brass screws (one headless) into a ceramic insulator; another, shorter insulator is threaded onto one end and fastened to the bottom of the box.  The lower plate has two corners clipped so the wires from that side can get to the terminals.


     There's a trick to working with such thin metal.  You can drill it, but it's risky -- even with a backing, it can catch and tear.  A better bet is to mark hole centers with a sharp awl and use a Roper-Whitney punch,† which will center up on the awl-made dimples.  Careful work with a hand reamer or chassis punch will enlarge the holes if necessary.  Small holes can just be punched with the awl, especially in places the punch wont reach.  (The lid does fit square, when properly seated.)



     My little SWR analyzer says it's not terrible on  the 80 meter ham band and not bad on 40 -- the ferrite I used was supposed to be good through 30 MHz, but the match start getting worse and worse by the 20 meter band.

     Checked it with the RME-45 receiver and Millen "Junior" transmatch and it works okay, slightly better signals with it between the antenna and the matcher.  80 meters was a jumble of noise this afternoon.  Just went down (10:20 p.m.) and turned on the receiver; as I tuned past 3885 kHz, a voice came out of the speaker: "Hello, Bobbi!  C'mon Bobbi..." 

     That got my attention, as you might expect.  I dodged the slow-rate tuning back and forth a little, and he came back on, "[callsign], this is [other callsign], c'mon, Bobby, if you're not there I'll just call CQ, CQ, CQ , this is [othercallsign] and remember, people, don't buy coax jumpers, you build your own.  CQ, CQ, from [other callsign], c'mon..."

     So I wasn't hallucinating.  And I was certainly glad I'd made my own coaxial jumpers!

     Next step, rebuilding the transmit/receive switch and moving the DX-60 transmitter over to the new shelves.
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* As close to Bakelite as you can get now.  McMaster-Carr stocks it in a variety of sizes and shapes.

† Mine is actually a Whitney-Jensen, an earlier model with a few minor differences.  These useful little devices are widely available used. Plugging the name into a search engine brings up a lot of listings at online auction sites.

Saturday, April 04, 2020

Cooped Up? Vacation From Your Desk!

     BBC has a delightful collection of "Places That Don't Belong," geopolitical anomalies all around the globe.  Many of them were hard to find or difficult to get to even before we were all staying home -- but you can visit them online!

     I may have to plug my Raspberry Pi into one of the big TVs and go on a tour.

Friday, April 03, 2020

Friday!

     I don't have much for today.  Just try to be nice -- socially distant doesn't need to mean socially rude.

     Supposed to rain here this weekend.  I hope they're wrong about that.

Thursday, April 02, 2020

And It Keeps On

     Being poor sucks.  I've been poor.  A couple of times, I have been so flat broke, I didn't know what I was going to do next.  You get through it, but I lived on a diet of ramen and hot dogs, of store-brand canned soup, where the occasional can of corned beef hash is a treat and restaurant food, even drive-through junk, is reserved for holidays.  I learned to mend jeans and to keep work clothes just for work; at home, old jeans and a T-shirt or a nightgown and robe was good enough.  There were better times, too; but they never lasted and there was no counting on them.

     When I first went to work at my present job over thirty years ago, the improvement in food I could afford was an unbelievable bounty; they handed out $30 grocery-store gift certificates at Thanksgiving and every Christmas, the company parked a freezer truck at the back door and handed out boxes of hard-frozen meat: two or three steaks, a nice ham, over five pounds of high-grade goodness.  It was remarkable; I started cooking again and slowly got to where I didn't feel as if going out to a dinner where someone else wasn't picking up the check was a frivolous waste of money

     Dealing with what coronavirus worries are doing to grocery-store shelves feels like being poor again.  I tend to focus on what's available, what I can make work for multiple meals, what I can safely store for later.  Just like decades ago, I worry about next week and next month.

     Of course, I'm not alone.  Most people are feeling this, and a lot of them didn't start with the stock of food and supplies Tam and I have on hand. 

     It's normal to fret a bit in times like these.  That doesn't make it better but maybe it makes it a little easier to bear.

Wednesday, April 01, 2020

So, It Occurred To Me...

     ...All over the First World, children who have been picky, fussy eaters are being told, "Well, that's what we've got, so eat it or go hungry."

     I take this with the slightly malicious glee of a spinster aunt, reminded of my mother's story of  staying with one of her much-older sisters for a couple of weeks one summer.  This would have been some time between 1938 and 1941; Mom was grade-school age and her sister was out of college, working, and not yet married. 

     Times were hard, money was tight, and if you think the wage differential between men and women is significant now, it was far more so then.  Mom was the very youngest, and accustomed to having her own way.  Her sister lived in a small apartment, downtown in a fair-to-middling southern Indiana city

     One day, lunch was chicken noodle soup, bread and butter, and milk.  Mom had decided after a few spoonfuls that the soup was not to her liking.  She ate her bread, drank about half her milk, and looked around, complaining that she was hungry.

     "Well, then, finish your soup."

     "It's awful."

     "I see."  A streetcar bell clanged outside the window.  "Oh, there's the trolley!  Go have a look!"

     Thrilled as only a child can be by such a connection to the wider world, Mom rushed over to the window and watched as the trolley car stopped, passengers got off and other got on, and the motorman dinged the bell and sent it trundling away away.

     Her sister said, "Come back and have your milk, and you can go play."

     Mom returned to the table, picked up her suddenly-full milk glass, and chugged it -- realizing, too late, that the glass was now half-milk, half chicken noodle soup.  Raised too polite to spit it out, she finished her "milk," and took the lesson to heart -- or at least well enough to heart that when she had children of her own, she made sure we knew what might happen.

     My siblings and I all learned to finish our soup.

     Perhaps a new generation of children is learning to eat what's set before them -- a lesson that may have wider implications than just at mealtime.

Tuesday, March 31, 2020

Morning Assortment

     I've got to get to the grocery this morning and see about assembling a week's worth of groceries, so today's post is a little hasty.  Along with that, Holden the cat is still learning that cats are not allowed on my desk at breakfast time, a rule about which he expresses great doubt.
 *  *  *
     But let's talk about a few things, data and ways to present it among them.

    One of the best books I can't remember the title of, a book ostensibly about commercial art, had a very good section on how to avoid telling lies with charts and graphs.  It is staggeringly easy to do so, intentionally or not, because of a few factors.

     The first is that we love a pretty picture.  If scales and hues need to be adjusted to get an eye-catching presentation (or just to fit the  page or screen), we will do so.  You end up doing things like over-emphasizing small variations between very large numbers (commonly done by rescaling or trimming bar charts or graphs to remove "all that wasted space.)

     Another is that while most of the growth (and decay) processes in the world tend to proceed logarithmically, our perceptions and expectations are linear.  Even our senses scale exponentially rather than linearly.  In the very short term, the straight line and the swooping curve track closely enough to get by -- but in the long term, they diverge rapidly.  Once a processes gets started, it ends up going like a rocket!  That's why, outside of a few hard-hit and early-onset areas, you're probably looking around and thinking, "Hunh.  Not much of a pandemic."  In NYC, ERs are packed, gurneys in the hallways, and they're nearly out of ICU beds.  Even here in Indianapolis, the biggest hospitals are starting to feel the pinch -- and we've got a couple weeks to go before the peak, if present predictions hold.

     A third is confirmation bias: we're good at cherry-picking what we see or read to conform what we already expect.  This is the bane of experimental work, and why in things like drug trials, there has to be a "control" group, who do everything your test group does -- except use the drug under test.

     A fourth is "granularity."  For the United States, the Johns Hopkins coronavirus map only goes to the county level; for Canada, case data is per Province or Territory, and for most of Europe, it's per country.  These are not sections of equal population; they're just handy chunks that probably reflect how the data comes in to JHU.  The IHME data and predictions, on the other hand, are state-by-state at their narrowest; you're not going to find anything about measures taken by cities and counties on their pages, though it may affect their predictive models.  You can't read this data any deeper than it goes.

     Fifth and last, our good old friend, Dunning-Kruger Syndrome: we don't know what we don't know.  Heck, I can do math, I can read a study written in plain English -- why shouldn't I make my own predictions?  One reason would be that I don't know how good a model a locked-down cruise ship full of the kinds of people who can afford to go on a cruise might be for a large American city, full of a wide assortment of people doing a wide assortment of things; YMMV, but remember, there are folks who make a living doing this sort of thing and the reputable ones are extremely cautious about inferring too much.

     Please, let's just do what we can to get through this.

Monday, March 30, 2020

Predictions

     There's a very good site with national and state-by-state predictions for the course of COVID-19.  It's run by the Institute for Health Metrics and Evaluation (IHME), a think tank that describes themselves as having "the goal of providing an impartial, evidence-based picture of global health trends to inform the work of policymakers, researchers, and funders."  They've got a nice, fat $279 million grant from the Bill and Melinda Gates Foundation to do it with, free and clear.*

     When it comes to COVID-19, they, like the rest of us, want to know what's going to happen next.  To that end, they are collecting and collating data as it becomes available, refining their models and updating it daily.  Unlike a lot of such sites, they include not just the median prediction, but error bands as well: they're willing to show the limits of their knowledge and their models.

     The state-level predictions I have looked at (many) are a good fit to what I know (not much) and have extrapolated.  New York and many of the surrounding states are in serious trouble; a lot of the Midwest is in better (but still worrying) shape.

     Have a look.
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* Paranoid rants incoming to comments in five, four, three....  You know, writing that in all caps isn't going to improve the odds of my letting it through the filters.  I have been patient with people's irrational suspicion for years, in large part because I figure all our institution need watching and it's a great way to keep the 'noids usefully busy; but there's a limit and I reached it some time last week.  Not every comment I sideline fits that category, and I am sorry to have had to hold up quite a few good ones because they included assertions I could not verify, or digressed into political partisanship that serves no useful purpose against this pandemic.

Sunday, March 29, 2020

"Flattening The Curve" vs. "Business As Usual"

      If you're a member of the "Oh, it's no worse than a bad flu season" set, you might as well leave now, and take a look at the video coming out of Italy and NYC on your way: this thing hits hard and fast, compressing a flu season's worth of deaths and cases requiring hospital support into a few weeks.  Too many, too quickly for hospitals to cope.  Health-care workers are falling ill at a much higher rate than the population at large: they have to get universal precautions right every time, while the virus only needs to get a solid toehold once.

     The thing that social isolation and stay-home orders sets out to accomplish is not quite like a classic quarantine order used to contain something like measles, where quarantine and contact tracing can stop an outbreak in its tracks.  COVID-19 appears to be infectious for a couple of weeks before symptoms appear.  By the time you know you're sick, you've already been spreading it.  The best we can hope for is to slow it down.


     Slowing it down will save lives.  It will save many more lives indirectly than directly: The goal is to keep from smashing our healthcare system so flat that it takes years to recover, and does a much worse job coping with the surge and its aftermath.

     Nobody seems to understand that facilities and personnel are not going to bounce right back from an Italy-type caseload. Few people grasp that every patient in a hospital suffers when it is overloaded by a surge of COVID-19 patients.  A lot of people will die of a lot of things while we learn this lesson.

     In Marion County, Indiana, my county, we've got 676 known cases as of midnight.  That's about fifteen to twenty times as many as a week ago.  We're two or three weeks away from the peak if present projections hold.

Saturday, March 28, 2020

How Do I know It's A Pandemic?

     Because the COVID-19 heat map at Johns Hopkins has nearly one-to-one correspondence with population density, at least for the United States.

     Like most of my generation and subsequent ones, I grew up in a world of cure (or at least treatable) disease.  Throughout my adult life, the planet has kept issuing little reminders that it's not a simple battle; we just got a big one.

     The models for coping with this look like the more-successful responses to the 1918 - 20 influenza pandemic, or London when they best coped with Plague.   We cannot stop it by sheer force of will.  There's no bluffing a blind, biological robot.

     And no matter what we do, this is going to hurt.

     We had good years, good generations.  My Dad and Mom grew up fearing polio but my sibs and I didn't; my nieces and nephews didn't.  We've all got the scar from our measles vaccination.  Antibiotics have been truly miraculous -- I would have succumbed to childhood rheumatic fever were it not for penicillin and later drugs.  It was a halcyon time and now it's over.

     We're back to the 1930s at best in dealing with this virus.   There's no magic bullet, not yet.

Friday, March 27, 2020

If You Like Crunching Numbers

     Here's a decent set of charts and graphs, presented with straightforward, factual description and discussion.

     Remember, having a helmet fire is never helpful.  Knowing the facts is usually helpful, if there's anything you can do; and if there's nothing you can do, it's at least entertaining.

     I'm still home with what I hope is kidney stones.

Thursday, March 26, 2020