Welcome to the N1IR Electronics Website. Totally off the cuff, one take, unrehearsed video projects for anyone interested in amateur radio, electronic design, makers, hardware hackers and science.

Get off you duff and build something!
Training the hand and mind since 1982.

Monday, January 18, 2016

FTDI Cable to Bluetooth HC-05 Programmer

Here is a board that can program the HC-05 Bluetooth Module using AT commands.

All that is needed is a momentary reset switch and a SPST and a resistor. Didn't bother with a PCB because it would be one of a kind to program about (40) BT Modules. With the blimp project we need to rename each module to prevent confusion, Stock name is set for HC-05.

Steps to rename HC-05 Bluetooth Module
Open the Arduino IDE
Setup correct comm port that the FTDI cable is on
Select tools and open Serial Monitor
Set for 38,400 Baud

Set Switch to PROG
Push Reset Switch to place HC-05 Board to AT Command Mode
Type AT
Should reply back OK
Should reply back HC-05
Type AT+NAME=(new name here)
Should reply back (new name here)
Set Switch to RUN
Push Reset

Schematic Coming Soon!

Monday, January 4, 2016

Engineering Academy Blimp 2016

Engineering Academy Blimp

Step 1. Place (2) 8 pin SIP Header as shown below. This is to help you properly line up the board in the next step.

Step 2. Place TB6612 H-Bridge board, IC side down. Pin 1 is PWMA

Step 3. Get Main PCB from Mr J. Pictured below

Step 4. Place (2) 14 pin SIP headers as shown, notice the the headers will not stay in place

Step 5. Place TB6612 H-Bridge board in the bottom most rows of the SIP. This will hold the SIP sockets in place so you can solder and keep pins aligned.

Step 6. Solder the four corners of the SIP Sockets, then check alignment.

Step 7. Once alignment passes, solder the rest of the pins on the SIP socket, with sharp diagonal cutters cut the LEFT SIP socket Flush to PCB. This will help the battery clip lay flat.

Step 8. Place Battery clip. And solder on the componet side of the PCB shown below

Solder POS lead

Solder NEG lead

Step 9. Unplug the TB6612 H-Bridge board and put aside. Get a BT board from Mr. J, Desolder the pins. They are facing the wrong direction

De-soldered BT Board

Step 10. Place straight 6 pin SIP, as show below, long side of the lead facing down, short side of lead plugs into board.

Step 11. File the top of the TB6612 H-Bridge board about 20 strokes, mileage mat vary. This will trim the board do it can fit next to the BT board.

Step 12. File the side of the BT board towards the SATE pin about 20 strokes, mileage mat vary. This will trim the board do it can fit next to the TB6612 H-Bridge board .

Step 13. Plug TB6612 H-Bridge board back in

Step 14. Get a 6 pin Right angle SIP connector

Step 15. Place the 6 pin Right angle SIP connector on the top right hand side on the SIP socket, this is to connect your (2) motors later.

Step 16. Plug BT board in the top left hand side on the SIP socket. If tight fit refile the boards to fit.

Step 17. Place the 6 pin Right angle SIP connector on the top left hand side of main board, this is the programming header.

Step 18. Get (2) glass beads and 16 Mhz crystal

Step 19. Place glass beads on to crystal leads, this will insulate the crystal from the top layer solder pad

Step 20. Solder in crystal, make sure the glass beads are on the leads.

Step 21. Insert (2) 22pF capacitors and solder them in

Step 22. Insert 10K ohm resistor next to Pin1 of the IC, Solder in place.

Step 23. Insert .1uF (labelled 104) capacator next to Pin 1 of the IC, Solder in place.

Step 24. Insert (2) 470 Ohms resistors, Solder in place.

Step 25. Insert LED, Long lead (+) faces the IC socket, Solder in place.

Step 26. Insert 3 pin SIP into the servo position, Solder in place.

Step 27. Insert 22uF SMT Capacitor and remove right angle SIP

Step 28. Plug in BT board

Step 29. Get (2) .01uF (labeled 103) capacitors for draw A35 in the parts room, cut one lead of the cap short.

Step 30. Thread cap though tab on motors, solder

Step 31. Cut leads flush with motor tab

Step 32. Add red/black STRANDED twisted wire (6" long") to each motor Look for the + symbol on the motor attach the red wire to this.

Step 33. Place Right angle header in helping hands

Step 34. Strip, tin and solder on the short side as shown below.
From left to right No Connection, No Connection, -M1, +M1, -M2, +M2

Step 35 Inspec and plug into main board, motors toward bottom edge.

Friday, January 1, 2016

Blimp PCB Test 1

Got the blimp control board up and running heres some pics

The new blimp runs a Arduino, Bluetooth HC-05 and TB6612FNG H bridge, servo not pictured

Things that are missing from the test circuit, IC sockets (2), battery socket. All major components plug into IC sockets for module design.

Bluetooth Phone APP, using MIT app inventor 2

Coming soon!



PCB files

New Camera

Finally got a new camera for the web site, so you should start seeing more posts

Tuesday, December 22, 2015

PCB from China 3

Just got in the new blimp boards for work. From http://dirtypcbs.com/ . Turned out great really impressed

Heres some pics

Text size
Hole Size
Trace Size

Tuesday, December 1, 2015

Camper fan speed control

During our last camping trip we really need to control the exhaust fan over the stove,  it was really cold out and the fan was a bit to strong. So I came up with a couple ideas:

1. Use a resistors to drop the speed. The problem with this is the power loss. Don't forget were on batteries and do no wish to dump energy as heat.

2. PWM - this would be the most efficient use of power and would not required expensive components.

Here is the schematic:

Used vero-board for this project since it was so small

Frequency of PWM is out of the range of hearing so it's quiet, I originally tried 1khz PWM frequency on the breadboard but it made the motor sound like a screeching cat. So I made C1 smaller until i could no hear the PWM.

Monday, October 19, 2015

LM555 Protoboard

Making prototype circuits using a solder less breadboard

Many people are confused the first time that they have to build a circuit. How to connect the components together? The easiest way to get started is by using a solderless breadboard. A breadboard is a tool for holding the components of your circuit, and connecting them together. It’s got holes that are a good size for hookup wires and the ends of most components, so you can push wires and components in and pull them out without much trouble.
At right is a typical breadboard. There are several rows of holes for components. The holes on the breadboard are separated by 0.1-inch spaces, and are organized in many short rows in the center, and in two long rows down each side of the board. The short horizontal rows in the middle are separated by a center divider.
The pattern varies from model to model; some breadboards have only one strip down each side (like this model from Radio Shack), others have multiple side rows, and so forth. The basic model, with many horizontal rows separated by a central divider and one or two long side rows, is what we’ll focus on.
On each side of the board are two long rows of holes, with a blue or a red line next to each row. All the holes in each of these lines are connected together with a strip of metal in the back. In the center are several short rows of holes separated by a central divider. All of the five holes in each row in the center are connected with a metal strip as well. This allows you to use the holes in any given row to connect components together. To see which holes are connected to which, take a multimeter and a couple of wires, set the multimeter to measure continuity, stick the two wires in two holes, and measure them with the multimeter. If the meter indicates continuity, then the two holes in question are connected.

This image of the back of a breadboard may help to clear up how the holes on the front of the board are connected. The backing of the board has been removed (don’t remove the backing on your own board! It will make the board useless) to expose the metal strips connecting the holes. You can clearly see the short strips in the center separated by the divider, and the long strips down the side. The detail photo to the right illustrates how the holes and strips are related.
The reason for the center divider is so that we can mount integrated circuit chips, like a microprocessor, on the breadboard. IC chips typically have two rows of pins that we need to connect other components to. The center row isolates the two rows from each other, and gives us several holes connected to each pin, so we can connect other components.
When you start to put components on your breadboard, avoid adding, removing, or changing components on a breadboard whenever the board is powered. You risk shocking yourself and damaging your components.
At left is a typical use of a breadboard. We have an IC chip (in this case a BX-24 microcontroller) straddling the center divider, connected to several of the rows of middle holes. At the top, a 7805 5V DC voltage regulator is connected to three of the middle rows. The 7805 regulator is also connected to the side rows of pins. Its ground pin is connected to the blue rows of holes, and its +5V output is connected to the red rows of holes. This way, the red rows of holes can be used to supply 5V, and the blue holes allow us to connect to ground. Note how the BX-24 is grounded by connecting the row that its ground pin is in to the blue rows with a short green wire. It is also powered by connecting the row that its +5V pin is in to the red rows with a short red wire. Note also the LED and resistor connected to the BX-24’s bottom left pin (pin 12).
In this detail , you can see that the resistor and the LED are connected in series between the BX-24 and ground (the blue row). A second row of middle holes is used to connect the LED to the resistor. Compare it to this wrong detail . Can you see what’s wrong with the second circuit? The resistor is short circuited, because both of its ends are connected to the same row!
In the first detail above, you saw components connected in series, by connecting one end of one component to a row, the other end to a second row, one end of a second component to the second row as well, and the other end of the second component to a third row. Components can also be connected in parallel on a breadboard. At right, the three LED’s are connected in parallel using two rows. They are then connected to power and ground by connecting the rows to the red power row and the blue ground row.
Many options are possible using a breadboard, which is what makes them very useful and convenient for building circuits. Once you understand which holes are connected to each other (and which ones are not), you can build any circuit very quickly.
It’s a good idea to keep your circuits neat. When possible, shorten the leads on components so there is no bare metal sticking up from the breadboard. Make sure no wires cross each other with metal touching (this is the biggest source of short circuits on a breadboard). Lay things out as sensibly as possible, so each component of the circuit is near the components it needs to connect to. Use wires when needed to separate parts of the circuit that are crowded together. Use consistent colors of wires when possible; for example, use green or black for ground connections, red for power connections, white or blue for data connections, and so forth. This will make your troubleshooting much easier.

Exercise 1

1. With a ohm meter verify the pins on the breadboard that are connected together

2. With a pen please mark on the diagram below what pins are connected together; please show both rows and busses.

Mr. Johnson’s tips on a making successful circuit.

RULE 1). Be Neat with your wires

Here is an example of a good quality-wiring job.

Here is an example of a poor quality-wiring job.

RULE 2). Do one section of the schematic at a time then test that section (small steps). Don’t wire the whole circuit and expect it to work the first time.

RULE 3). Use different color wire for different items

Red for Positive Bus Voltage (mandatory)
    Black For Ground Bus(mandatory)
    Purple for Base of Transistors
    Orange for Collector Of transistors
    Yellow, Green, Blue for each individual Connections between IC’s

RULE 4). Quality, Quality, Quality. Instructors do have the right not to troubleshoot your circuit if it is messy and hard to follow.