SMD R, C and Diode Test Meter

I first started using SMD components in Homebrew Electronic Projects, because they are much cheaper, smaller to store, and the NEW more interesting functions are only available in very small SMD packages. Also, since my early days at Hewlett-Packard, I have always enjoyed working under a microscope on new and interesting things.

As a hobbyist, the one tool that I have always wanted was a good SMD Multifunction Tweezers Test Meter to measure SMD component values. When I first started with SMD's, there was only one very expensive Multifunction Tweezers product available, and if I remember correctly, it was about $1200. Over the years, they have come down in price. I think now they, and the "knockoff" brands, are around $350.

These more expensive Tweezer Meters will "Auto Scan" for; Inductance, Resistance, Capacitance, Diodes, and simple Continuity. All of these functions would be nice to have.

SMD Component
Testing Tweezers

But, $350 is still more money than I want to spend on a Meter.

Recently I found an interesting Tweezers Test Meter,  with maybe a fewer functions at Adafruit.com for only $27.95

Such a Deal ! At that price, I can not afford to be without.

Yes, this model has a few less functions than the expensive sets, but it is similar to the cheaper "Tool Box VOM" that we all have, it should get the job done.

This tool, provides Resistance, Capacitance, Diode, and simple Continuity testing (no Inductance), which are just exactly the functions that are most often needed. Along with my Soldering Iron, I expect this to be my "go-to-tool" on the build bench.

I ordered the Tweezer Test set from Adafruit (along with a few other components/parts) late Friday afternoon, and then received the order on Monday afternoon (shipped from New York to Seattle). Adafruit must have one heck of a Order Fulfillment process that can process an order, and then pick-and-pack products for over a weekend delivery.

A followup post will be provided after I have used this meter a few weeks.

FYI: I am not an agent of Adafruit, I am just a happy customer. The image used within the post was obtained from the Adafruit.com web site without their permission, I hope they will not object to its usage here. 

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WIFI for Our Projects

I remember reading (many years ago); With the invent of the Internet, we would eventually have many in-home devices that would be addressable and controlled via an IP Address. The prediction suggested that even the common Light Bulb would someday be networked.

To date, there are many "computer devices" that are controlled via an IP Address, and many of them are connected via WIFI.

But so far, many Light Bulbs (or LED) still do not have IP Addresses.  The big reason for this is the expense of the compute power needed by each addressable device. A computer or controller is needed to perform the complex network functions, like; TCP/IP Stack, DHCP. Authentication, and General Data Transfer. For most hobby project developers, the complex networking software development is the most difficult impediment.

But, a relatively new device, the TI CC3000MOD (at $20.00) does all the network hard stuff at a relatively low cost. The CC3000 is programmed and data is sent to/from a project device via a simple two wire SPI interface. The actual chip is a little hard to work with, because of its physical small size, board layout, antenna requirements, and soldering methods.

But, Adafruit.com has a new product which uses the CC3000 to make it easy to include WIFI Networking in a controller project.  (Yes I know, my blog is starting to sound like a Adafruit commercial, but they are one of the leaders, and provide some great inexpensive project components. And, No, as stated in other blogs entries, I do NOT work for them. I just really like some of their products.)

Adafruit CC3000 Breakout Board, with Integrated WIFI Antenna *

The Adafruit.com CC3000 Breakout Board (at $35.00) is a small pre-assembled board that can be attached to any project with only a simple 9 pin header. Programming, control, and data transfer is via the 2 wire SPI interface. Complex TCIP/IP stack programming is NOT necessary, as all of the hard work is done by the chip and/or included libraries.

Note: other configurations are available which include external antenna connector and Protoboard space.

I plan to order a couple to experiment with for my future projects.


* As stated before, the photos has been taken from the Adafruit web site without their permission, hopefully they will not mind for this use and recommendation.


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Trinkets

OK, my parts were received from Adafruit.com, see previous post.

The USB Power Gauge works as expected, it is very handy to check the charge rate on my Cell Phone, and for checking power consumed by any USB device, including my Raspberry Pie and/or the BeagleBone computers. The USB Power Gauge provides information that is otherwise a little difficult to obtain.

I had also purchased three Adafruit Trinkets. I followed the recommended software (Ardunio IDE) install instruction, and modification needed for the Trinket. And then, I proceeded to "Brick" all three Trinkets (or at least that is what I thought). I have used the Ardunio Interactive Development Environment (IDE) many times in the past and was not expecting any problems.

Because the "Trinket" has only 512 Bytes EEPROM (boot loader ROM) part the loader (about 1.5K bytes) is placed in FLASH RAM, which leaves about 5.5K bytes for user programs.

While loading a user program into the remaining FLASH RAM, if something goes wrong, part of the boot loader can be overwritten, and therefore it is somewhat easy to "Brick" the Trinket.

Instructions are provide to "UnBrick" the Trinket, but that requires yet another Arduino and downloaded programs.

While reading many pages on the web trying to understand my problem, I discovered that for Linux machines may not support USB in the way that the Arduino IDE for the Trinket desires. The recommended method is to use a external USB Hub to connect the Trinket to a Linux computer.

It worked, . . . how or why, I do not know !!

The Trinkets were NOT actually Bricked, . . . they just looked and acted like it. While plugged into a Hub, they now respond as desired by the Arduino IDE.

My first task was, of course, to run "Blinky", the "Hello World" program.

Once that worked, I quickly put together the following CW sketch to send/blink "CQ" on the LED.

/*
  This Sketch Blinks CQ on the LED
*/
 
int led = 1; // blink 'digital' pin 1 - AKA the built in red LED

int WPM = 13; // Words Per Minute
int ditTime = 1200 / WPM;
int dahTime = ditTime * 3;

// the setup routine runs once when you press reset:
void setup() {
  // initialize the digital pin as an output.
  pinMode(led, OUTPUT);
  delay(2000);

}

// the loop routine runs over and over again forever:
void loop() {

    for(int j = 0; j < 3; j++) {
      dah(); // C
      dit();
      dah();
      dit();
      eoc();
      
      dah(); // Q
      dah();
      dit();
      dah();
      eoc();
    }
    eow();
    
    delay(10000);
}


void eoc() { // End of Charactor
    delay(ditTime * 3); // added to previous End-of-Char time
}

void eow() { // End of Word
    delay(ditTime * 7); // added to previous End-of-Char time
}

void dit() {
    cwpulse(ditTime);
}

void dah() {
    cwpulse(dahTime);
}

void cwpulse(int duration) {
    digitalWrite(led, HIGH); 
    delay(duration);
    digitalWrite(led, LOW);
    delay(ditTime);
}


// End   

A more complete and non-trivial CW sketch would be table driven, but this was quick-n-dirty just to just get something to work.

More complex and interesting programs will hopefully follow.

I think the Trinket will have a place in my bag of tricks, for small Ham Radio Projects. I am currently thinking of maybe a Beacon Trinket Shield, and/or a Tennis Ball Launcher Trigger Controller.

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New Products I Plan to Order

There are two new little products that will make my planned projects easier, both less than $10 each.

The first is a little (inline) USB Power Gauge:

I have several (many) small battery-powered devices that are Charged or Powered via their mini or micro USB connection. For example: a cell phone, mini speakers, keyboards, video cameras, micro-controllers (e.g., Rpi), and several others. I think standardization of chargers and/or power for some devices is great for users, but.

I find that sometimes information is lacking regarding the state, or status, of the device being charged. The devices idiot power LED does not always tell the story. On some devices, the battery does not seem to take-a-charge, or it charges very (maybe too) slowly. The charge rate is typically dependent on the USB charge voltage, the active Application current draw while the device is being charged, or some other unknown reason. I have waited overnight for something to be charged and disappointed with the results the next morning. Without a meter it is difficult to know what is going on, or how to fix the problem.

Adafruit.com is producing a new "USB Power Gauge *" and it will be inexpensive. I plan order one when they are available (in maybe 10 days or so).

Adafruit USB Power Gauge *

The second new little product is a small "Adafruit Trinket"; an Arduino-Like Project Controller:

The Adafruit Trinket has some very interesting spec's, and will be just the right size, with a small pin count, for some projects that I have in mind. With this controller and a simple Arduino Script, all of our Ham projects can be made "smart".  The Trinket can be purchased for 5 Volt or 3.3 Volt circuits. I will include several of these when I place the order from Adafruit.com.

 Adafruit Trinket - A Very Small Project Controller *

* Images were obtained from the Adafruit.com's Web Site, without their permission. Hopefully they will not mind for this endorsement. I do not work for Adafruit, I just really like some of "Lady Ada's" products.

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UPDATE: Oct 17, 2013
Parts are now on order.
I also added the following to the order:
Heatsink Thermal Tape - http://www.adafruit.com/products/1468
Heatsink - http://www.adafruit.com/products/1493


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Part Quest

I am always looking for Small Parts for my projects.

For most of my projects I have standardized on a simple Battery connector, it is the same style that is used in many of the Propeller and Arduino Products. The connector is shown here attached to my PA-47, which is a Homebrew 15 Watt HF PA.

The Battery Connector on 
My PA-47 Project

The actual connector that I have been using is a little different than those that are readily available. This connector has smaller tabs that are used to solder it to the PCB. Because the tabs are smaller, this same connector can be use with proto-breadboards (with only a little difficulty) . The tabs are not exactly the size the breadboard would like. but it works. Also, because the pins are little smaller they fit into round drilled holes in the PCB. Note: Most of my PCB suppliers do not allow plated slots as necessary for many other battery connectors.

My Favorite DC Connector
for  Projects
(unknown to me at the time,
this is a PJ-102A)

My stash of these connectors is almost depleted. Somewhere along the way, I got the (wrong) idea that these connectors were called "PJ-007".


A quick (causal) search via FindChips found the PJ-007 was only available from Digi-Key, I had several other parts that I had planned to order from Digi-key, so I ordered 20 each PJ-007's, for about $12.00

 The True PJ-007

Received, BUT NOT!  what I wanted !

I received the PJ-007's, they are a similar style of connector, but they are about 1/2 the size that I was expecting. My quick and "Causal" search was too quick - now I have a bunch of very small connectors that I will probable never use.

I would have to look to my other suppliers and/or try to remember where I had previously purchased the desired connectors.

After several days of searching and trying to remember, I eventually found my source at Adafruit. But, the search of the Adafruit site was not exactly easy, as this part did not match any key words that I tried. I finally gave up and looked at the complete list of available parts, but still no joy.

https://www.adafruit.com/products/80

I eventually found the connector on the Adafruit site as a "suggested part", while viewing the available 9 Volt Battery Clips (which is a nice clip with wires and a end connector).

But Adafruit description of the "suggested part" did not include a manufactures part number, there was just an order ID number - 373. I plan to add a few to my next Adafruit order.




But then:

While attempting to re-layout my PA-47 Board to correct and add some new features, I did a quick check of ALL of the parts and patterns before ordering a new set of boards. While looking at the Library part for the Battery Connector, I noticed that it included a spec sheet and URL for the connector. With a little research of the manufacture I found the desired part is a PJ-102A. A quick check of FindChips.com suggested the part is available from several suppliers.

Several PJ-102A are now on order.

Until next time, my small Parts Quest, . . .  goes on.

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