Making: A $20 Parts-Meter & How to Use It

If you’re into robotics, computers, electronic circuit design, fiddling, or you’re a ham radio hobbyist wanting to spend more time on the boss end of a soldering iron, my friend Jeff at the local ham club turned me on to something called an “M-Meter, parts meter and assorted other names.”

What makes this a useful tool is it answers one of the more troubling problems face by newcomers to electronics;  which is “Just what it this damn part I’m looking at?

Pretty cool, too,” I was assured. Just plug a part in and it will tell you what you’ve got!”  Given the number of eye operations I’ve been through, anything that lightens the load on the eyes is “all good.”  Besides, the Parts or M-Meters are dirt cheap – about $11-bucks on eBay for the working board and I splurged for an $8 acrylic specially-made box to put it in.

(*Continues below)

 

The first step in assembly is to lay out the case parts to get an idea of how things to together.  There’s a QR code on some of the packaging.  But, while the Chinese may believe all American’s own iPhones, there are those of us on slow circuits and out of cell-range in the woods.  I already warned you some tablets – like my new Kindle HD 10 will not focus close on small QR’s, right?  Still, it’s an enclosure for crying out loud — how tough could it be?

Essentially, you get two big pieces of clear acrylic.  The one with the plentiful screw holes is the bottom, while the one with the cutout for the component test-bed goes on top.  Not hard stuff.

Just remember that on the two long side pieces, there’s one with a cut-out and this is placed adjacent to the top where the test socket (and lever) are located.  The side cut-out lets the lever move to the locked position.

There are four long screws and nuts;  also four screws that are short with nuts.  The short one are used with small plastic stand-offs to hold the CPU/ display board off the case.  Eventually (since rocket science is what we do around here, yeah?) I figured the four long screws with nuts would clamp the case together.

After using those untrimmed fingernails (no one who actually makes things trims their nails, I tell yah) the paper is off the plastic parts (they look water-jetted) and you’re ready to, er, screw.

The standoffs go under the printed circuit board (PCB) and they will only fit one way with the holes lined up…

If you look closely, you will see that Ure’s truly has spread out a micro fiber cloth to work on.  Several reasons for this:  Acrylic scratches if you so much as look at it crooked.  I buy large packs of the micro fiber towels from Amazon.

Micro fiber clothes are cheap:  $10-bucks for 25: S&T Bulk Microfiber Kitchen, House, & Car Cleaning Cloths – 25 Pack, 11.5″ x 11.5″. These come in multiple colors.  Which I use for different projects.  Yellow and green are for electronics, other colors are for automotive and milling and metals.  Adds to my delusion that my shop is orderly and organized…

While getting fingerprints of hot vacuum tubes (which can cause hot-spots on high power tubes) these micro fiber god-sends are perfect finger-print getter-offer for all things plastic.  A quirt of Plexus Plastic cleaner ($19, but great to have on hand for all things plastic) and it will look like new.

Did I mention that the dropped tiny screws are easier to find when you drop them on a yellow micro-f shop towel? (Gotta do something about my floor, lol.)

Just before the top cover goes on the parts meter, don’t forget to toss in a really fresh 9-volt battery.  Although the unit is simple enough to hold together (after you’ve gone through the dropping curve to hold the case together while putting in screws and nuts one-handed because you’re too lazy to get the masking tape to help…) this is not something you want to plan as a centerpiece when entertaining.  Repeat after me: PITA. Get the masking tape to hold things together and then remove.

How Does It Work?

Cool!

In Ure’s Lab, all the pill bottles I’ve ever handled live in some semblance of order.  So, I was able to quickly pick some difficult projects for the parts meter.  I wanted to see just how good it with do with this and that:

Can we bring out our first candidate, please?

If you squint at the lower corner of the meter, you will see it is 10.13 nano farads which is what the part is labeled in my (surprisingly neat) parts collection.

You just need to remember on capacitors there are conversions to get from micro farads to nano farads, to pico farads, which is newspeak for micro-micro farads which is redundant redundant!

It’s just that there are three ways to state something like capacitor value on older schematics of radios, robots, and whatever:  In this case, the choices are 0.01uF / MFD,  the 10nF nano farads, or the 10000pF (MMFD) where MMFD really means uuf (now pico farads) if you’re a grown up.

Doe it work on all values tried?  No.

Had something of an issue with small capacitors like 47 uuf,  (47 pf).  BUT it got the small chokes (inductors) about right – and that’s what it will be used for.  Inductors, also called “coils” or “chokes” have a color coding system 300-feet past stupid when your eyes are sub-Optimus Prime.

Come to think of it, lots of components are little Decepticons.  What the hell is a capacitor vale (disk ceramic) of “103???”

A dandy article over at Robotoid here goes into this occult other-earthly capacitor language.  Or, you plug the part into the meter like this just-assembled parts meter  and out pops the answer.

Is it the be-all, end-all?

Far from it, eventually you will end up with a sizeable meter collection that will eat up most of your bench space if you don’t keep them locked up and prevented from reproducing.

Left to right:

The first meter is the new parts meter.  This will take a stab at playing “Name that component.

Second one is an Equivalent Series Resistance (ESR) meter.  This will take a whack at capacitors including (with a dozen asterisks) in-circuit caps with 50 asterisks.  One of which is that table on the front of it which requires a magnifier for older techs like, uh…you know!.

Meter #3 is used when you don’t believe the ESR meter.  It’s a pure capacitor meter, BUT it will go wonky on some capacitors (big broadcast silver-micas don’t read well, for example).  Unsolder one end of the capacitor you’re wondering about because it doesn’t do in-circuit well..

The last meter is a simple transistor and IC checker.

“How Many Meters Do You Need?”

Dang!  That is a toughie.  If you are doing “simple” robotics, then a “grown-up” meter with a current clamp, probes, holster, and all that makes sense.  Take out $235 and get a Fluke 117/323 KIT Multimeter and Clamp Meter Combo Kit.  But, what about inductance?  Try the on-sale for $11 Digital Multimeter, HOLDPEAK 4070L Manual-Ranging Multi Tester for Measuring Resistance?Capacitance, Inductance, Transistor, hFE of 2000 Count (Blue).

When people ask me “why so many” I use the water analogy to electricity.  Voltage is like the water pressure.  Current is like the cubic volume of water flowing.    The “pressure” (volts) times the “amount of current flow” (amps) gives you the amount of “work being done” (in Watts).

Ergo, voltmeters, ammeters, and watt-meters.  This “parts meter” is really an inexpensive subset of LCR (inductance, capacitance, resistance) meters.  There are lots of them available with the main feature change being whether the unit is auto-ranging or if you have to spin a switch to find a reasonable reading.

Measuring Alternating Current (AC) Voltages

When messing about making things, we have Alternating Current (AC) as well as Direct Current (DC).

It’s not so simple as you’d think:  Alternating current (AC) has two major ways of being measured:  One way is “peak-to-peak.”  This is from the top of one cycle to the bottom of it.  Assuming symmetry…another longish debate,  Peak-to-Peak reading.

Unfortunately, while it’s true that Peak Volts and Peak Amps will multiply into a number giving Watts (instantaneous work done), the REAL number in the power world is called RMS – stands for root-mean-square).  You use RMS to get to average work done,.

DON’T USE THE PARTS-METER in today’s project to test AC lines!!!  Use a real meter – Fluke 117.  Insulation matters!

So, if you (CAREFULLY WITH EXPERIENCED SUPERVISION) stick a peak-reading AC volt meter into a dryer plug you might find peak to peak is 339 volts.  To convert this to RMS, you multiply times 0.707 and THAT is what the power company will bill you on.

EXCEPT even THAT refined number is not really a pure one.  Because of something called “power factor.

Regulators (does the term “lying lazy pieces of crap” come to mind here?) have been sold the idea that utilities should bill everyone on the basis of a power factor of 1.

What this means, without going into the engineering side too deeply, is that it the power company is allowed to ASSUME that peak current and peak voltage arrive at your appliances at the same time.

They don’t – not in the real world.  When the peak current shows up at a different time than peak voltage, you may pay for one kilowatt-hour of work and only really get 0.80 kilowatt hours!

Think about this closely. If the current and voltage are totally out of phase:  Peak voltage arrives when there is ZERO current, so no work will be done.  Since 240 volts times ZERO amps in this worst case nightmare is zero amps, the dryer won’t dry clothes well.

Same thing other way around:  If peak current arrives with zero volts….

Back to the robotics angle:  This power-factor discussion is not academic.  Because in robotics the easiest way to control power is using pulse width modulation.  PWM.

Instead of nice, smooth sine waves like come out of your wall, PWM robotics controllers slice or chop Direct Current on and off.  For light loads, it’s a paper thin slice of voltage.  For a heavy loads a bigger ‘slice of power’ is used.  Think of PWM as different thicknesses of sliced breads.  Thin slices give you less energy..

For complex power (PWM) you won’t use a parts meter or even an LCR (unless looking for a faulty component).  the right tool for complex wave forms is an oscilloscope.

That’s beyond the discussion in this week’s making oof stuff, but the point is, you need as many meters as you’re planning to mess about with.

If you cover from DC to AC daylight?  OMG.  Not only will you need volt and current (and capacitor and component) (LCR) meters, but you will need precision voltage sources to test and calibrate things. And an oscilloscope.

At the end of the day only simple questions remain:  How much precision and over what kind of range?

The ultimate limiting factor – though seldom stated – is “How much are you willing to afford?“”  There’s always like any other hobby, if you have the money, someone’s got something really cool to sell you.

Test equipment for messing about is no different.

Now, off to play with the ham radio: Computer: turn on the tunafish!”  (See the Coping section on voice automation hell this week….got it worked out, lol.)

Write when you get rich,

George@ure.net

Making: Landscaping Improvements & Tractorfying

Saturday morning, after working the bugs out on the Peoplenomics server (new security update, CHMOD issue) it was time to get on to the first Make project of the weekend.  “Purdying up the yard.”

The first thing you do is touch off the pile that’s been accumulating for a few weeks.  The idea is you light off one side of it using what we call a “cactus burner” and then push the unburnt side into it.  That way, you’ve got great control of your fire.

This doesn’t seem like a big deal if you live inside a city and the fire department will be there in less than five minutes.  But, out here in the Outback, one respects the volunteer fire department, pays the annual membership dues promptly, and then watches all outdoor fires like a hawk.  Even so, we have had two fires near us already where I was one of the people on tractor-back making sure the fire stayed contained.  A drought’s on the horizon, and we expect the Texas Forest Service will be busy this year.

(Continues below)

 

People sometimes don’t appreciate how much damn work can be done with a small to medium sized tractor.  Let me show you a “before and after” of a stand of yaupon at the base of a keeper tree.  The first picture is from the tractor looking at the victim plant.

This second picture is a pass down and back later.

Less than 90 seconds.  Gone, mulched, done, and off into the deep woods.

There is some debate locally about what to do with yaupon.  Oilman2’s son, who’s been known to tractorfy a bit here ’round, is allergic to the stuff.

I’m none too fond of it, either.  On the other hand, since NPR has a story over here on the interesting past of the yaupon, maybe a hashtag (like #saveyaupon) will pop up with us at the center of a Trump-sized hate movement.  There’s just no telling, these days.

Still, American holly or just a damn nuisance, some of it near the house had to go.  So did a number of small trees that were blocking some of the young pine stands coming up.  You use the tractor bucket like a gigantic weed puller and then get the offending tree on the bucket and head for the fire.

When you get there, you drive into it as you dare.

This is one of those “judgement” things city slickers don’t think about.

OK, you need the tractor because it’s the main line of fire defense should the weather have been drier and the wind up.  But, in order to keep the fire heaped up (and thus burning clean, not spread out and smoky) you like to dump fuel into the middle of the fire.  But the tires will burn, so you are quick in, quick out.

Once the small stuff has been piled on, you go looking for big dead-fall.  Trees that have fallen down on their own.

You can see how far this downed tree hangs off the bucket on the right.  It dangled just as far off the left.  So, getting to the fire is a series of Z-turns through the woods; first the right side goes by a close tree, then a hard turn right to get it past the next tree on the left, and so on.  A diesel ballet.

Eventually, something always goes wrong when you are tractoring.  No, not if you’re a gentleman farmer on a manicured property. Nothing goes wrong there since you have unlimited funding.  But here?  Uh….

Out here in the Outback, it’s a constant battle to keep Ma Nature bound and tressed-up just so.  She, in turn, responds by getting the tractor stuck in soft ground at a low spot.

I’d taken on a LARGE defiant tree, maybe 20 feet long and fatter than me.   There was no alternative but to do an end-push to get it to open ground where it could be more easily moved.  The only way to get there was through a shallow drainage ravine.  Four-wheel drive or not, that’s where I got stuck.

The old farmer has lots of options, so that getting stuck is not the end of the world.  In fact, it can be an excuse to stop work for coffee.  One way to get out of such a predicament is to push the bucket down and using the power-tilt of the bucket, digging the teeth in – thus creating a great-big lever on the front-end.

That’s an easy one sometimes because you don’t even turn off the machine.  Just lock up the 4-wheels and let ‘er rip.

Except this time, it just dug in further.  The second option was to see what was holding me in position.

Answer: the brush hog.

Solution:  Lift the front off with the bucket to take the strain off the top link of the three-point. Unhook the top link, and  then pull like hell.  That worked.  Dragged the brush hog on the lower links.

After fighting a bit more with the big defiant log – this time armed with a hundred feet of 5/8ths line (Texans call it “rope” but remember, we lived on a sailboat and a 11-years of sailing sailing the salty seas hasn’t rinsed off even 15-years on).  Finally, I said to hell with it. Articles to write, beer to drink, and so on.  The ham gear needs to be used, too.

Besides, the rain had picked up – it was 11:30 AM now.  Another axiom of “working your land” is don’t do heavy work when the ground is really wet.

Soil around this part of the property has lots of clay in it and this means if you compact it down, too much, it is a bugger to get much of anything to grow in it.  Think planting in concrete. So, the tree gets to sit in a new place for a while longer.  A chainsaw will be applied at the right moment in the future.

With the rain was coming down, and now semi-soaked, it was nice to visit one of the dead cedar trees which we have left untouched so our wildlife has good homes.  The hawks and the owls like it.  Pretty tree, too.  It may be standing longer’n us:

Who said making landscape improvements can’t be gnarly?

purist on the topic of Making things might argue that landscape work is not “making” per se.  I’d suggest, any time you sculpt anything – metal, wood, and today even the forest, it’s all part of the continuum of making that distinguishes us from the Apes.

Even the ones who don’t look up from their phones.

Write when you get rich (or done),

George@ure.net

Coping: Personal “Hints & Kinks”

Making is great fun.  But, one of the hardest choices we’ve set up for ourselves is what to make.  Each choice seems to have its own  set of hints & kinks that make the pursuit pleasurable…yet it’s hard to find all the little hints collected in one place.

My first encounter with Hints and Kinks was in the ham radio journal QST.  Don’t run off – I’m just saying that ham radio is a fairly complicated sport.  so much so that Hints and Kinks is now updated about annually.  In 1954, it was on Volume 5…to give you an idea how deep the topics run.

Robotics  and both the Pi and Arduino crowds will no doubt get Hints and Kinks for robots going – if they aren’t already.

(Continue below)

 

There more traditional sports – hunting and fishing, to name a couple – already have huge compendiums of hints.  Why, just the hints and secrets to reloading (at the match level) could fill several books.

Same with fishing, too:  Depending on fish, sunlight intensity, time of day, moon cycles, wind, bugs, jet skis…why there have to be a million hints on just selecting the right fishing spot.

Medicine is loaded with “differential diagnosis mapping” as expert systems come along, but what we don’t have yet is the “Expert System Shell” software product we could all sure use.

Let me describe this idea for you:

You know how there are basically six types of software, right?  Word processing, spreadsheet, communications, databases, graphics, and games comes most things, though a few insist utilities should be a seventh category.

What we don’t have is this thing I’d call the 8th Wonder of the World – let’s call it 8WotW for short – which would be a standardized, free, expert system.

Imagine it like a resident version of Wikipedia that lives on your phone or desktop.  Except instead of looking up just a single topic, you would first select the information domain first.  Then, you would be able to navigate (in menu-tree fashion) to the specific data that you’re looking for.

I’d call this an expert system shell.  But unlike most – generally compiled by knowledge engineers, you’d be able to jump right to the heart of Babel of any topic in half a dozen clicks…maybe more, but follow along here.

Let’s say I want to paint.  I have the basic concept of painting in my head.  So I open this new software product (8WotW) and I select a Domain of Doing.

That would be Art.

Then under all the different forms of art (music, ceramics, carving, modeling (like model railroads and dioramas, right?) we come to Painting.

Next choice I have is Paint Type.  Hmmm…Elaine’s acrylics are sitting out…so I click on this.

Now I come to the Process section.  It offers me processes for Layout, Design, Paint Mixing, Order of Work (workflow), Brushes, and on like that.

Having never done a painting before, I whip through the Layout – make some mental notes, glance at design…but then I find exactly what I didn’t know:  Painting (oil or acrylics) is generally done from background to foreground.

AH HA!

This is what I have been doing wrong.  I had previously painted in no particular order and didn’t have a clue what I was doing.

Pressing the “HK” (hints and kinks) icon, I discover that the back to front is only done with layering materials.  If you are doing pencils, gels, charcoals, then you art in foreground and then sketch in background…

Point is, there is all this useful knowledge out there, why hasn’t anyone figured out this 8WotW so that instead of going through a million data entries and clicks (search Google, search Bing, search YouTube, search Vimeo, search Yahoo Groups, search….yada yada yada…) we don’t have this open source 8WotW idea out there and then have open-source publishing of “modules” of content?

Let’s say I’m out in the shop.  I get into a woodworking project and come up with a question.  I don’t want to get all over the board and waste an hour on the computer.  All I wanted to know was a question about sanding sealers prior to painting.

I would jump right to what I’m  doing:  Wood>Projects>furniture>finishing> sanding and hit the HK (hints and kinks) button.

Ideally, this would pop up with the world’s current state of the art in sanding sealers which could then be searched using any of the standard domains outlined in The Millennial’s Missing Manual.  I might be finishing wood in a house, something which might contact food, rolling stock like a car, a wooden phone stand in communications, and so forth.

And while at it, please give me the choices prioritized by cost (you might have selected time, but that would get you into lacquers and such and we don’t like volatiles around the shop because they might limit investigations into welding, casting, or electronics where sparks might show up…

The idea is that Wikipedia is a great fact-base and sure, the HTML links in each (most) articles work, but for general MAKING of things, why not a knowledge framework and then accessible online specialties like woodworking, auto repair (by make?), boating (power or sail), art, and on and on?

The tools are in the works.  I’ve mentioned this a number of times in past years on the Peoplenomics.com side of the house because it will be the basis for the widespread use of what I envision as A.I.-Lite.

That a look at the Disciple project at George Mason University, which we have covered before: They have it called  “Knowledge Engineering: Building Cognitive Assistants for Evidence-based Reasoning.   And yes, you can download the code.

I would recommend a book, first: Knowledge Engineering: Building Cognitive Assistants for Evidence-based Reasoning will set you back $78-bucks and I don’t know how far it will go toward what we’re talking about here.

But the HUGE INNOVATION step that people miss when talking about A.I. is we will shortly have the capability to take something like the Disciple code, cobble up a consumer front end for it (8WotW) and use a small fraction of its intelligence to building useful knowledge on the fly.

And that, my friend, is where MAKING takes a leap.  Because when we figure out how to deploy the A.I.-Lite against problems like the perfect Creator outcomes we’re after as Makers on weekends, it will then give us a path to using such A.I.-Lite tools to do things like learn and automate our stock-trading concepts.

And that, my friend, is where the evolution of Hints and Kinks from the ham radio people, could be leading us as knowledge engineering moves of the white board and into the living room.

Write when you get rich,

George@ure.net

Making: The Rest of the Amplifier Story

Making:  The Electronic Detective version of the story was fun to write, but it didn’t get deeply into the  making/fixing part of the linear amplifier project so this morning I wanted to run through the process of restoring an old piece of electronics.

Process, you see, is a HUGE factor in whether a person is successful at anything.  And, just as we have reduced the complexity to building a home to just four basis processes (measure, cut, join, finish) there is a similar series of steps that can be applied to “all things making.”

Those steps are:  Assess, hypothesize, troubleshootize, repair, re-assemble, and test.

(Continues below)

 

Assessment:

When you use a piece of gear for the first time, you put it through all of its paces and figure out what isn’t working right.  So for the amplifier, here were my observations before putting the unit on the bench:

  1.  Switching was all working normally.
  2.  An odd arcing was sometimes seen, but there was no component smell.
  3.  The amp would not make full power.  Max power out was about 300-350 watts with very little screen current and plate current was only hitting 250 ma. maximum.
  4.  Observationally, the bias voltage regulator tube was not igniting under any of the Mode settings.

There are (sadly) people in the ham radio world who will take their “golden screwdriver” to a perfectly good piece of equipment and just start twisting things (almost like an ape, randomly trying this and that hoping a fault will cure itself).  Surprise:   That won’t!  BUT all that “magic screwdriver” will almost certainly break other things!

Hypothesize:

I knew that the amplifier SHOULD be making full power output which I would expect to be in the range of 500-800 watts.    I looked at the schematic from the output of the rectifier where the jagged DC is cleaned up:

Starting at the Upper right (-BIAS) I knew this would likely be where my issues were.  I circled the actual faulty component which we will come back to.

The point is that I had hypothesized ahead of time which section of the amplifier was giving me problems before getting the cover off the unit.

Troubleshootizing

Sure enough, measuring things out with an ohm meter, and following the manual’s “typical resistance readings” I measured from pin 2 of J102 to ground.  By the book, this should be either  4,000 ohm or 9600 ohms, depending on mode.

The 4000 ohm resistor had failed open.  So I had my problem solved…or nearly so.

The best news about that resistor being open was that it solved all of my problems in one fell-swoop.  That’s because:

  • When the resistor opened, bias voltage INCREASED.  And, as we all know from Tube Theory 101, too MUCH bias reduces an amplifiers output.  Bingo!
  • Further, we then knew why the 90 Volt regulator tube was no longer working:  When the voltage went up, it went past its design specs and that was the end of the regulator tube.

Since I had figured this might be the case in Hypothesizing, I’d taken the preemptive step of ordering both a new rectifier and a new regulator tube on eBay this week.  Both came to like $11-bucks.

Repair:

This is where having large hands is not a good thing.

The replaced part is that white boxy-thing (a 10 watt 4.7K ohm [k is 1,000 so 4.7K is 4,700 ohms) resistor plus a couple of other resistors from the junk box).

There’s a good story to the resistor:  All I had in my junk box was the 4.7K which was too big.  And, I didn’t have a large second resistor that would work.  So hitting one of the Online Calculators, I did the substitution using 4.7 K plug (2) 56K ohms in parallel.

This is where the two most important formulas in troubleshooting are useful.

I knew that the likely output voltage of the unloaded power supply might be as much as 150 volts.  Using  Volts divided by resistance to get current (E/R = I) we solved current as 0.03191 amps, or about 32 milliamps.

Using this current, we could then use the voltage times current to tell us how much Power would need to be dissipated.  This is remembered as P=IE.  Power equals (I is current) time (E is voltage).

With the voltage across our resistor network being 150 (we’re guessing), and current of 0.03191, this means about 4.8 watts.  With the 4.7 K being well over, we were safe.  But, what about those two 56K resistors?

150 volts divided  by 56K (56,000) gives us current of 0.00267 amps.  And take that times our 150 volts 0.408 watts.  We’re in luck!  The 56K resistors are 1/2 metal film types!

Repair 2:

The other problem that remained on our list was the mysterious arcing.  You may recall, one of our readers said it might have been a cat hair…

It turned out, however, to be a loose circuit board on the top side of the chassis.  You see, the fan is mounted to this board and as you can see in the picture what happened.

When the board slid to the right, only ONE of the blades on the fan got close enough to arc…which it did in fine fashion.  All the while, though, I was looking to replace the cracked-insulator on the plate RF choke, or tear out the door-knob type high voltage capacitor  (the brown thing left).

Since the arcing was only happening when the board heated…well, it was one of the stranger problems I’ve seen.

Repair of this problem was not fun.  It involved taking out the entire filament transformer to get at the bolts, long-ago covered-up.

Reassemble and Test

With all the faults identified, it was almost heartbreaking to wind up the project.  Repair of tube type radio equipment is incredibly satisfying to me.  Tell me if this looks like something built in 1964 when I got done with it:

Almost hated to plug it in and have it just work.  Oh well, another day, another Making.

When I did plug it in?  My oh my!  Key down the amplifier will put out 750 watts to the antenna.  More cool than the raw power is that the amplifier also gives a reassuring thumping sound (as the big power transformer such down the line voltage) when keyed.

Yep…that’s what we love in ham radio:  Something that will dim the lights when keyed.

Totally tactile world-changer for those brave and bright enough to use Morse…the original digital mode.

Write when you get rich,

George@ure.net  (de ac7x)

Making: The Electronic Detective, Case #1

Making:  it’s what people do on weekends.

In our first episode, we will tackle a medium-complexity problem in electronics.

While many people are put-off by such endeavors, with an almost superstitious belief that there “is magic in all those wires and parts” nothing could be further from the true.  In fact, electrons always follow the rules of simple physics – much to the consternation of poor humans, ill-equipped at times as we are to understand and follow such rules…  So to this weekend’s adventure!

(Continues below)

 

The Electronic Detective

The Case of the eBay Amplifier

Allow me to introduce myself;  I am the Electronic Detective but my parents named me Phaselock Home. I operate my detective consultancy from L-21(b) Inductor Street, not far from High Pass in the Filter district.

The case began with an amateur operator trying to recreate his ham radio childhood.  His “Elmer” had owned a Drake 2-B receiver with the 2-BQ Q-multiplier.  The transmit side consisted of a Gonset GSB-100 and a Johnson-Viking Courier linear amplifier.  A TA-33 (Junior) beam sat squatly on top of his single-story house, raised by only a 6-foot tripod.  A repurposed AR-22 TV antenna rotator moved antenna headings.  It was 1964.

Amazingly, in side-by-side testing, my client’s Drake 2-B was as sensitive as his recent (2015) Kenwood TS-590S transceiver.  Not as stable for digital modes, though.

The GSB-100 worked well, also, save some sideband suppression issues that promise another case, should my client be unable to follow the straight-forward directions for alignment common to to phasing-type SSB equipment.

The amplifier?  Well, that was a different matter.

My client, you see, is a vintage radio addict.  He learned to always enter a “Make Offer” bid 40 percent lower than the “Buy It Now” (BiN) prices on eBay.

In this case at hand, a $400 offer, plus a small fortune for shipping, was accepted for a complete, working Johnson Thunderbolt amplifier.  Buying with the “make offer” option ensured that if later resold, the odds of a profit would be higher.

Upon its arrival, additional help was hired to help move the beast.  Watt’s son was fortunately at hand allowing 125-pounds of “desktop” equipment to be moved into position.  My client had inspected the unit, and installed necessary tubes.

But, he was confused by large number of voltage regulator tubes.  The marking of tube numbers were unreadable on most.

Here, my years of experience paid-off.  Taking a tube, I rolled and rubbed it through my hair as my astonished client picked up his jaw.  “Those things are dirty!” he exclaimed.

While indeed they were, the fine oil from the human hair adheres to the places where the numbers used to be. As the numbers appeared, we were suddenly able to sort out an ancient OC3 from a a nearly identical looking OD2, and so forth.

Next came an appearance issue:

The Thunderbolt had a crank to move the rotary inductor as it left the factory.  So I demonstrated how a piece of wooden dowel, and a 1-inch long 8-32 screw could be made in one’s drill press.

Esthetically, it was not a permanent repair.  A painted screw head, preferably Phillips, would be located later, along with some hollow black plastic tubing of suitable diameter.  But, when prosecuting crimes against the spectrum, expediency is paramount.

A further problem was the antenna change-over relay – smashed in shipping.  Its robust mechanical parts were intact, but the leaves of the relay, where contact is made, had been bent into useless condition.

With 20-minutes labor, the relay was disassembled and parts bent-around, just so, to make them work as desired.

Those “buttons” at the end of the relay were the issue.  They are shown here after my client learned the art of “relay detecting.”

The Thunderbolt, I instructed, was an odd duck having no internal provision for transmitter-receiver switching.  The most solid arrangement, although a bit 20th Century, involved the use of two antenna relays drive by switched transmitter AC provided by the GSB-100.

If you inspect the picture, you will see that un-powered, the top two buttons are connected.  We call this a “normally-closed” (often abbreviated NC) position.  When energized, the relay center pole (the next leaf down) disconnects from the NC and contacts the third leaf down.

When not transmitting, as in the photo, there is no path from the second leaf to the third making this contact “normally open” – abbreviated “NO.”

These three wires are mechanically pressed into a jack  (lower middle) here, in the lower left of the photo.

I’ve given my client instructions to continue his quest for a proper plug to make with this socket.  But, since this is a 1964-era amplifier, the number of necessary components to create a “factory-fresh” restoration are very limited.

My client is still looking for Johnson Part # 22.1190 to mate with socket Part # 22.1191.

Our time is limited, but the Electronic Detective does offer elucidation to his clients.

Related to this case, observe as follows:

1.     The amplifier in question offers a superior product compared with typical grounded-grid designs.  “Modern” amplifiers, you see, were designed to be drive by the prototypical 100-Watt (output), usually Japanese-made, single sideband transceiver.  “Old” ham gear can be virtually any power level.  In fact, you can drive a Thunderbolt to a full 2KW PEP (input) with a low power radio such as an Elecraft K3 or even the new uBITX, a $119 (including shipping!) all band transceiver out of India! (http://www.hfsignals.com/index.php/ubitx/ )

2.     This flexibility comes because the Thunderbolt does not drive the cathode (which is how grounded grid amps are driven).  Instead, they are grid-driven.  Admittedly, there is more complexity.  Those three wires on the Thunderbolt switch operating and cut-off bias on the two 4-400C amplifier tubes which are nearly the same (though shorter) than the 3-500Z tubes.

3.     While grounded-grid amps are most commonly cut-off when not driven, a grid-driven amplifier is not.  Which is why bias-switching becomes important.

4.     Sources for restoration parts include eBay for most things, including tubes and such.  The Boat Anchor Manual Archive (BAMA) [http://bama.edebris.com/manuals/]  is the premier source for FREE copies of manuals.  Surplus Sales (of Nebraska) has many odd connectors – they’re moving so we haven’t found a Johnson 22.1190 from them yet.  K5SVC (who runs an eBay store) has good prices on tube sets, while Hayseed Hamfest offers an assortment of newly-built (to spec.) can-type capacitors and complete radio re-cap kits.

The Electronic Detective doesn’t recommend a serious boat anchor project of this sort for your “first-time, out-of-the-box” encounter with ham radio’s glowing tube-enabled past.  Not only are there LETHAL VOLTAGES involved (which can hurt ‘all the way dead’), but you’ll need to remember that mercury-vapor rectifiers (such as the old 866-A’s) need to be “cooked” for several hours before first user after shipping so as not to arc-back internally.  That can be expensive.

In a further adventure, perhaps with the help of Watt’s son, we will tackle something simpler: A quick restoration of a triple-conversion receiver.

For now, I’m back to chasing Moriarty, again.

No, not the villain.  You see, I have as my goal this year to work half of the 80 hams who live in Moriarty, New Mexico!  I missed all of them in yesterday’s running of Winter Field Day.

To the bench, Watt’s son!  And bring a meter.  The solder’s a-smoke!


With that, the Electronic Detective put on an oddly shaped piece of head-gear:  A Danish Army helmet replica from WW II.  No point holding to convention, around here…

Coping: With the “Artistic Urge”

Every so often, I get the “urge to art something.”  (No “Where’s the f?” jokes, if’ you please…)  Problem is, like most people, I haven’t discovered my “gift” in art, yet.  Writing doesn’t count, lol.

When I think art I think of things like what my buddy Gaye over at www.strategiclivingblog.com talks about in Pursuing Your Passion: Getting Started With Adult Coloring.  Since we’ve been friends since ’73, or so, I’ve talked to her several times about this kind of art – and what she says makes it sound like something that might be worth trying.

Truth be known, I was a pretty good “paint by numbers” guy,  50-odd years back.  Want a million-dollar idea?  Come up with a paint-by-numbers kit that you could project onto your own canvas that would colorize the painting and put in the numbers for you.  THAT would be cool.

(Continues below)

 

My tastes in Paint By run to paintings like these:

As you will notice, I like rural, mountains, woods, and waterside things in general.

But, like I was saying:  If there was a service where I could send in a picture, like the boat we lived on for the first year and a half we were married, THAT would be fun to turn this into a painting.

Since the “regular” painting kits, in the 16X20-inch range, run in the $15 and under area, I would think a $50 kit with the right paints and the numbers would be a really cool service.

Maybe it’s out there and I just haven’t stumbled into it yet. But, if someone has done it, Paint By Numbers (PBN) is a form of making.  And all making is good.

Meanwhile, Elaine’s got a corner of the guest quarters/gym staked out for her artsy side.  She’s one of those people I envy – not needing numbers of lines to stay in…

There’s actually a forest scene that will emerge from that canvas one of these days.  A big problem painting while looking out at the woods is there’s just so damn much to see.  It’s distracting as hell… deer, owl, hawks, cats…it’s all out there somewhere lurking.

Activity Scheduling for Later in Life

As much as I would love to be working on a painting – that’s just one more time sink in life I don’t need right now.  Still working on web site revisions – which will be done— when they’re done.

Doing a paint-by-numbers looks to me likek something that could be pushed back into late-stages of life.  Assuming there’s not too much of a palsy, of course.  Heck, even if there is, it’s just turning that into a bazillion brush strokes.  Not stippling, but near enough…  Attitude and overcoming is the point of life, is it not?

For now, I can still handle most of the Big Work around here single-handed.  Where I need/or cautiously rent – a hand now is for high work on ladders and such.  Cleaning out gutters, comes to mind.   Sure,  CAN still do it all, but statistics say that’s dumb.  

Lifting heavy weights (much over 80 pounds) seems like an unnecessary strain, so those go onto the “for hire” list.  Painting the house might be on it this spring, too.

On the other hand, gardening seems like it could go on much longer (80 something?) IF you have been studying that weed-free gardening book I mentioned to you recently ( Weedless Gardening by Lee Reich).

Reich’s approach doesn’t involve turning over the soil – and that appeals to me more every year.  Love-hate- with the tiller this time of year.  We have plenty of pine straw around, toss in a few bales of real straw and a couple of 166-foot rolls of Trimaco Red Rosin Builders Paper, should  give us a good start on that Weedless Garden Reich writes about.  Five minutes to a half hour a week?  Pinch me.  More on this as we give it a try this spring.

At some point in aging, it will be time to shelve the power tools, too.  That may be when we get serious about moving to the ideal dream retirement home.

We keep collecting the list of specifications (one level, short walk to store, low crime, inside city, 3-minute medical response times, modest climate but not too cold, low taxes, no HOA ham radio nazis, etc.).

With that big picture done, the subordinated task becomes figuring out what hobbies, pursuits, and pastimes will be put into that “some day” dwelling.   Thing is, we know when people either don’t have projects, or if projects get stalled, then ill health almost automatically follows.

I was talking to a fellow who has an airplane for sale  (at the right price we still think about it…) the other day (flying, like sailing is something you never get over).  Gentleman selling a mint Cessna 175 is 80-something and has been retired for more than 15 years.  He’s building what will be his second or third airplane now.  An RV-4, if you’re interested.

Knows he probably won’t be flying it much.  But, as a retired A&P and inspector, he just loves keeping active.   “People die when they sit down” he confided…and we agreed.

It’s like that with ham radio around here.

We will be taking a number of casino trips this year – loading up the memory banks with some of the great entertainers who are still around.  Going to see Johnny Mathis is early March, for example.  Tom Jones in May.

You see, that’s the thing:  We don’t enjoy the cattle call experience or wife-grabbing that air travel has evolved into.  So, we plan to take leisurely drives.  A cruise now and then, maybe….sure.

But our main goals are to fill in all those blanks in life we’d never gotten around to earlier.  Write the Great Novel, find the hidden keys to life, master spiritual realms ahead of time…little projects like those.

Which gets me back to painting.  Even if rudimentary and by numbers.

I told you a good while back about Karl Hansen, one of the last of the real master model builders of sailing ships out of Portland, Oregon, was a friend of the family growing up.  He sailed them all:  Tall Ships from about age 10 as a cabin boy around 1890 on…

As an Able Body Seaman, he’d sailed the last of the big ships – ones used in the lumber and grain trades, mostly.  Knew every line aloft by heart and has been up there in gales around the Horn and more.

There’s a “doing magic” part to those eras.  Like the steam engines. Something more of a “hard contact sport” of life than the sissified world gone virtual, accessible, correct, and boring.  There’s still some frontier land in Texas, and many other states.  But the people are softer now, less determined, lacking the broad vision.  Don’t know how to put it into words.  But seriously, is getting consciousness out of a body and onto a chip a worthy goal or charade – a kind of last act of self-delusion by a world of people driven mad by their own devices?  Bit questions these.

It would be just a dandy decorating project for the “last home” to have something in the den/office that would be a focus on a single ship.  Maybe old Cutty Sark, or Thermopylae would be good.  Bigger?  Sure: something like this Model Shipways USS Constitution 48” Long Wood Kit. Easier to work the lines (shrouds, ratlines, and such) if you’re dealing with larger.  On the other hand, hand-laying the plank on frame models IS more difficult than an inexpensive plastic variety.

Plastic isn’t bad.  Hansen built a goodly number.  Where his genius was he knew better than modelmakers where each line went, what it’s purpose was, and how it was stowed.  Modelmakers who’d never been to see made some stupid decisions on some lines.  You don’t just put up lines for fun and appearance on a real ship, though.  Purpose…focus on that.

Between a painting, a good-sized model, and a writer’s over-active imagination with a penchant for travel, the whole package might be spun  into quite a painting, a finely crafted model, a book, or two, and travel adventure to see the old harbors.

I plan to continue banging on  a Morse key well past the medic unit showing up…and with so many books to read (and many more to write) it isn’t like there’s not having enough to keep us busy around here.

Still, when the sun’s out but still too cold for real gardening work, it’s tempting to eye the “art spectrum” and figure up how to  “stage” some of that into the order of appearance for the tail end of life.  I don’t think any of us every get to sample enough or it, though.

Assuming this smorgasbord doesn’t stay open forever, there’s still empty-space between our ears into which we can all pack a ton more experiences and knowledge – the currencies of the soul that you really can take with you when you go to the Big Sleep.

Busy people don’t die.  People with no goals, on the other hand, seem to be pushing themselves to the front of that line.

Additional Weekend Column?

Hobby and Making discussions:  I’m thinking about adding a column on Saturday or Sunday from time-to-time.  Topic would be Making & Electronics.

There are lots of “moving parts” to this little enterprise, but some of the more interesting ones (to me, personally) are those involving electronic projects.  Ham radio restorations, explaining the fine art of being The Radio Detective – plus I’m well over 100 pages in a slow-motion writing project I’m working on called “The Art of Ham Radio Repair.”

This is aimed at the retro tube-type equipment which is far easier (thus more fun!) to work on than SMT (surface mount technology).

So let me know if there’s interests in the further adventures at the dumb end of the soldering iron, scope, RF signal generator…etc. etc….

Been a ham since 1963 or 64 (memory blurs) but in that time I’ve made most every mistake someone can make…no reason you should have to…

Write when you get rich…

George@ure.net