Do you believe with a measly of $7, and you will get a 16F84 PIC frequency counter?

Well, in fact a counter would only cost you less than $2, while the LCD display will cost you a little bit more, which about $5 each.

Those simple and user friendly features in the 16F84 PIC frequency counter also elaborated the uniqueness of it as well.

There are several sophisticated characteristics in this frequency counter, and you might be having the interest on this project even more. Those features are:

A very cute stand alone frequency counter.

A comprehensive digital readout function, which you can eventually set the IF
offset to any of three combinations i.e.: VFO+IF…. VFO-IF or  IF-VFO with the mode switch.

Turn the frequency counter into a Gig region; with just a simple modification, (The additions will include the pre-scaler).

A typical 14 MHz count will be around this figure: 14.060.45.

Note: Make sure you can mount the frequency counter into a 2N2/20.

It is always a fun experience to build a simple and reasonably cheap frequency counter.

RMS G Meter is considered as one of the useful acceleration measurer that ever created.

RMS G Meter had been widely used in the following industries:

• Shipping - RMS G Meter is used for determine and verify the packages traveled with as little damage as possible.
• Manufacturing - It is used for vibration sensing for quality control purpose.

The proper ways to calculate the RMS:

1. Try to pick a function
2. Then, square the function
3. Remember to take the ‘mean value’ of the function
4. Lastly, do take the square root of the function

RMS G Meter is a smart microprocessor-based device, which can display and updates instantly the root-mean-square (RMS) values of the acceleration.

There are six main components in a RMS G Meter:

• An accelerometer
• Low pass filter
• A/D converter
• Microcontroller
• LCD display
• Battery power supply

We must know how to differential the four modes which:

Peak Mode

Once the PMS G Meter is activated, the device will update the highest RMS value it has measured.

Average Mode

The device will display the average RMS value of the signal all of the time since it had been activated.

Integrated Mode RMS

It will report the total of all RMS samples that has been computed since the activation.

The Instantaneous Mode

Display the raw G’s which measured by the accelerometer constantly.

You must wondered, building a frequency counter is a tough task, but is not as hard as you though.

Those materials that needed are:

• LCD 16 character x two lines
• TCXO 12.8 MHz (1ppm)
• PIC 16F84

Some of the features for this frequency counter:

• It can show the frequency in between 100Hz - 2.5GHz and the voltage (0-510mV) on the LCD display.

• Well furnished with IF offset-function, and can be applied for the frequency display with the homemade transceiver.

• Small sized circuit board with 10cm x 4.3 cm.

Now, you will learn how to deal with the IF OFFSET.

Firstly, when you see the RB3=H, RB5=H and RB0=H, this means it is a normal frequency counter with the power turned on.

When the SW for RB7 is pushed, the LCD will show “ADJ”. If you twice the tact SW for RCB is pushed, then the LCD shows “OFF” signal.

You will notice the RB5 and RB0 set as “H/L”, only after the power is turned off. In the final step, you now can make the display with IF OFFSET!

Would you think you’re smart enough to compare with the Einstein? If you are, then you should try to DIY this RV LED light controller.

Material needed:

1. A PIC 16F627
2. A standard 1141 bayonet bulbs
3. Twenty-one LED

We’re using the standard 1141 bayonet bulbs that cost less than 1/10^th power and it can also used as an emergency lamp, by placing a gell cell battery on it.

Some of the great features are:

• Three light output.
• Delayed off mode (Give you times to get into bed, before the lights go out).
• Half an hour auto off mode.
• Low battery voltage alarm (about 11.4 volts).
• No drilling or wiring needed to install it.
• It will maintain regulated light levels to 11 volts, by using the 21 ultra bright LEDs.

If you referred to the above figure, you will see the configuration as:

• Jumper from pin 5-6 show the auto off feature (You can remove this jumper if you do not want the light to turn off automatically).
• Remove the jumper auto off will occur after about 1/2 hour.

Jumper from pin 9-10 indicate the low battery warning (Remove the jumper if you dont want the low battery indication).

Do you love to challenge yourself off in the GPS niche? You have a deep interest in the GPS Locked Reference as well?
Ok, you might want to keep yourself busy with this 10MHz GPS Locked Reference.
Before you’re busy with the project yet, you need to check up the system requirements first:

• A voltage 10Mhz crystal oscillator (We want the tunable type);

• A GPS card (Use for outputs a detailed status message relating to its clock error);

• An external GPS antenna (for the GPS card purpose).

First of all, make sure you only use the 10MHz voltage tuned crystal oscillator, which the frequency is locked to the GPS positioning system clock. We use the Superstar single board OEM GPS receiver for this project.
Secondly, we now will replace the internal 10MHz clock on the GPS card. This replacement will take you some time.
Then, we use a PIC microcontroller to read the serial error word that transmitted from the GPS card. Remember to have the PIC output an analog tuning voltage to the 10MHz oscillator as well.
Finally, we now able to lock the oscillator to the GPS clock system. Project files.