Category Archives: Electronics

Rack mounting a Fluke 8846A and Fluke 8808A (A review of the Fluke Y8846D 19” rack mounting kit)

What?  Rack mounting a DMM in a home electronics lab?  That’s just plain crazy talk.

IMG_0426Space is at a premium in my home office. 

Long ago, I started rack mounting computer and networking gear in order to keep from getting overrun by clutter.  As a result, when I go shopping for electronics, it has to be quiet, rack mountable, and power efficient…  In that order.

I already had a fluke 8846A 6.5 digit multimeter and was planning on purchasing another lab multimeter, and I wanted to rack the two together.  After looking at various multimeters, I decided to get a fluke 8808A 5.5 digit multimeter after talking with several electronics test instrumentation vendors.

I purchased the Fluke Y8846D rack mount kit and am happy to say that the multimeters are now racked. 

This kit (Fluke Y8846D rack mount kit) is basically a shelf, with holes drilled into the sides to match up with the holes in the sides of the multimeter.  The meters fit onto the shelf, are screwed in on each side of the shelf, and have a filler plate which is pushed between the two meters.

IMG_0428Before I purchased this kit, I had a lot of questions and even asked a few equipment vendors whether or not I could rack mount an Agilent or Tektronix DMM (or power supply) next to the Fluke DMM.  The answer is not really.  The back edge of the shelf it bent up at a 90 degree angle which fits up to the back of the DMM.  My Tektronix power supply is too deep to fit and the shelf.  moreover, the screw holes on the sides of the instrument do not match up with the holes in the side of the shelf.

It works very well for the Fluke meters.

[Review] Evil Mad Scientist Discrete 555 Timer electronics kit


Three Fives - Discrete 555 Timer Kit

The “Three Fives” Discrete 555 Timer kit from Evil Mad Scientists is a transistor-scale replica of the ubiquitous NE555 timer IC, packaged as an easy to assemble kit.

And by easy to assemble, I mean easy.  The component values are clearly printed on the silkscreen on the board.  I never once had to look at the schematic or parts list.  In fact, I didn’t even look at the assembly instructions until it came time to test with the example circuit.


Building the Kit

DSC_0014The Three Fives kit is one of the easiest-to-build soldering kits I’ve encountered.  It includes the circuit board, PVC foam legs, resistors, transistors, 8 color coded thumbscrew terminal posts, and assembly instructions.

To build the kit, you will need the basic electronic soldering skills and tools: soldering iron, solder, wire clippers, and a Phillips head screwdriver.  That’s it.

Using the Kit

DSC_0018Since the kit is the equivalent circuit for an NE555 timer, you can lookup one of the hundreds of 555 timer circuits freely available on the internet and implement them with spare parts.  The only caution is that if you are using a power supply above 6.5V, you cannot connect the RESET pin directly to the 6.5V source directly; you’ll have to use a 100k resistor in between the connections.

The Weller WX2 Soldering Station Has Arrived…

IMG_0247Today, the “new” Weller WX2 soldering station has finally arrived and is in working order.  The saga began when I contacted Apex/Weller to upgrade the firmware to the latest version, and it bricked my control unit

I had purchased one of the original units as soon as they came out, and over the years the display had started to dim and it was getting harder to register presses on the touch screen.  As a result, they said they were going to send me a new unit.

When they said I was getting a “new” unit, I envisioned a shiny new unit in in a brand new box.  That didn’t happen.  This one was just bubble wrapped and packed in peanuts.  

In any event, I’m glad to have it back.  I was worried I was going to have to scramble to get a soldering iron for my EE term project.  In fact, I was shopping for a substitute soldering station when I stumbled on a promotion where if you purchase a WX1 or WX2 (or bundle) you can get a free hand piece.

Mix a few beers, quiet desperation, and a special offer like that and my brain rationalized purchasing a WX1 soldering power unit to get a free SMT tweezers set with stand…

I bricked my Weller WX2 Soldering Station

Update #2: Somehow, my address got mangled and the package got flagged as a wrong address.  UPS shipped it back without any notification to me.  It will arrive back at Apex in another week.  I’ve asked that they send me another one, but it was later in the day.  I’ll have to see if they ship another one to me without waiting for the current one to slowly make its way back across the country.  I’m really not happy with UPS right now.

UPDATE #1 :  Apex tools decided to send me a brand new WX soldering station because the LCD was dimmed. I should have it soon.

Friday, I tried to upgrade the firmware on my Weller WX2.  I had purchased the unit right after they became available in the US, and still had the original firmware (0.49).

Technical support sent me the updated firmware (0.64) and the upgrade instructions.  The upgrade process hung and after well over half an hour, I powered cycled the device to try again.

Nope.  It was bricked.

That’s when I learned that WX unit has firmware more than three or versions back, it will not update, in some cases.

Yesterday, I packed it up and shipped it off to Apex tools to be reprogrammed or replaced.

SparkFun’s Cheap Chinese Multimeters are Impounded by Customs, Unleashes Rage of the Internet, and Fluke Gives SparkFun Free Merchandise.

imageSometimes, I have to shake my head.

Yesterday, SparkFun posted a blog post which generated a lot of hatred for Fluke, entitled, “Fluke, we love you but you’re killing us.” 

A cyber lynch mob formed and legions of SparkFun defenders started immediately monkey hammering their keyboards in unison, indignantly telling Fluke they will never buy a Fluke Multimeter.  Fluke responded by promising to give SparkFun a truckload of their products, for free.

SparkFun is a multimillion dollar company, with over 130 employees, but still publically acts like an mom-and-pop shop with altruistic values.  I get it.  It works.  In 2010, SparkFun pulled in roughly $18.5 million in revenue1, almost all of it from products imported from China.

SparkFun had a shipment of 2,000 Chinese multimeters stuck in customs, which were impounded because they looked remarkably like the trademarked Fluke multimeters, even down to the curve of the sides of the meter.  These were made by an OEM manufacturer for SparkFun, complete with SparkFun’s own packaging and logo.

When U.S. Customs impounded them, without Fluke’s direct intervention, Nathan Seidle (CEO of SparkFun) threw a temper tantrum and threw down the “we-are-a-small-business” card being crushed by unfair rules.  Oh the tyranny.

Nathan stated that they were out $30,000.  I call bullshit on this.  $30k would be 2,000 * $15, the full retail price, not the actual price of the units.  But let’s not let facts get in the way of a good story.


So what did Fluke do?  In a classy move, Fluke decided to give SparkFun a shipment of genuine Fluke products to replace the trumped up losses.  That’s right.  It would give SparkFun, for free, a truck load of merchandise to sell or give away.

While I respect this as a brilliant public relations move to squelch the virulent firestorm, I’m somewhat saddened that SparkFun can rake in so much cash on the business model of selling Chinese merchandise not suffer any losses given the risks of selling only Chinese made merchandise.

On a side note, the $15 multimeter is listed as “CAT III Max 600V.”  There is absolutely no way that that multimeter would be able to handle CAT III power applications safely.  When questioned about this, SparkFun responded with…

Screen Shot 2014-03-20 at 11.17.35 PM


1 Bootstrapped, Profitable, & Proud

Review: Fundamentals of Logic Design, 7th Edition


What is the best book to buy to learn digital logic design?  Well, it’s not this one.  That much I tell you for sure.

If you are required to purchase this, don’t get the kindle version.  You will find yourself flipping back and forth between the practice problems and the text in order to try to figure out what you missed. 

And trust me, you will figure you missed quite a bit, because there is a dramatic mismatch between the text and the practice problems.

I found myself mumbling things like, “Convert 111010110001.0112 to octal and then directly to hex?  What page was that on?”  Oh wait.  It wasn’t.

The book is filled with many such puzzles, where you try to intuitively fill the gap between what is presented in the text and the practice problems. 

This book doesn’t teach the material, it punishes you and forces you to look for better information on the subject. 

EE101: myDAQ Educational Lab Kit Unboxing

As I’ve said elsewhere, I’ve decided to take some electrical engineering courses at the University of North Dakota (UND) as a distance student.

Remarkably, there are very few, if any reviews or information about the DEDP program online that I could find when I was considering enrolling.

As a result, I thought I would posted a quick review of the National Instruments myDAQ kit that is required by several of the electrical engineering courses, along with some comments about the program.

The $750 USB Cable Intelligence Test


We all know that marketers tend to stretch the truth.  But the audio industry plays by a different set of rules, because many “audiophiles” are simply too stupid.

I remember listening to a kid claim that he had to trim his audio cables to exactly the same length so the sound would arrive at his ears at the same time. I thought I misunderstood and I asked if he meant the speaker position.  No, he said speaker position didn’t matter as much as the cables.   Apparently in his universe, the speed of sound is faster than the speed of light.

Today, someone pointed me to an article, entitled the 2013 TAS Editors’ Choice Awards: Digital Interconnects.  In the article, the “TAS Staff” gave awards the $549 AudioQuest Diamond USB Cable, and the $750 Audioquest Eagle Eye USB cable among other expensive USB cables.

That’s right a $750 USB cable.  That’s not just a rip-off, it is an intelligence test.  If you purchase one, you’re not very smart.