Running Message Display

Light emitting diodes are advan- tageous due to their smaller size, low current consumption and catchy colours they emit. Here is a running message display circuit wherein the letters formed by LED arrangement light up progressively. Once all the letters of the message have been lit up, the circuit gets reset. The circuit is built around Johnson decade counter CD4017BC (IC2). One of the IC CD4017BE?s features is its provision of ten fully decoded outputs, making the IC ideal for use in a whole range of sequencing operations. In the circuit only one of the outputs remains high and the other outputs switch to high state successively on the arrival of each clock pulse.


The timer NE555 (IC1) is wired as a 1Hz astable multivibrator which clocks the IC2 for sequencing operations. On reset, output pin 3 goes high and drives transistor T7 to ?on? state. The output of transistor T7 is connected to letter ?W? of the LED word array (all LEDs of letter array are connected in parallel) and thus letter ?W? is illuminated. On arrival of first clock pulse, pin 3 goes low and pin 2 goes high. Transistor T6 conducts and letter ?E? lights up. The preceding letter ?W? also remains lighted because of forward biasing of transistor T7 via diode D21. In a similar fashion, on the arrival of each successive pulse, the other letters of the display are also illuminated and finally the complete word becomes visible. On the following clock pulse, pin 6 goes to logic 1 and resets the circuit, and the sequence repeats itself. The frequency of sequencing operations is controlled with the help of potmeter VR1.

The display can be fixed on a veroboard of suitable size and connected to ground of a common supply (of 6V to 9V) while the anodes of LEDs are to be connected to emitters of transistors T1 through T7 as shown in the circuit. The above circuit is very versatile and can be wired with a large number of LEDs to make an LED fashion jewellery of any design. With two circuits connected in a similar fashion, multiplexing of LEDs can be done to give a moving display effect.

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Heater Fan Controller

This device acts as a variable speed control for the heater blower in a car. It takes its power directly from the existing wiring and connects with just 2 wires. It will also work for any 12 volt device up to 10 amps.

A PIC12F675 provides all of the necessary functions. It reads the (10k) linear potentiometer and generates appropriately timed pulses to control the DC motor running the fan. The extreme low position cuts the power entirely.


The circuit is relatively simple. The wire to the blower motor (either high or low side) is cut and connection is made to the circuit with the more positive side at the top connection.

The diode and 100uf capacitor always provide full 12 volts because the Pulse Width Modulation scheme always provides a minimum 'off' time of the power cycle.

The LM78L05 (note unusual pinouts) provides 5 volts for the PIC. Depending on the setting of the 10k pot, GP5 sends out positive pulses with duty cycles between 0 and 98 percent.


The IRL7833 has a rated 'on' resistance of 0.004 ohms, so it can handle about 10 amps with just a small heatsink. The layout was done so as to maximize the current handling between the FET and the terminals (upper left area). When printing the layout, the arrow should measure exactly 2 inches.

Here are the Source and Hex files. Note the use of the watchdog timer function. Since this device is constantly powered on and off by the ignition and main blower switches, this provides hardware resets when needed.

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Automatic coming/leaving home light

Those days when I come home at night and strait into the darkness are finally over. This is a very practical device and I built it so that it is a module to my Dual Channel IR Remote Control. Because of that I ended up with a definite overkill of what is supposed to be a simple switch with a timer when I open/close my door. Anyway, it is modular+wireless and that's what I like.

You can download the project files (including the ASM source code for the PIC) at the bottom of this page by clicking on red "download" button.
Project separated into two PCBs (PSU+PIC and UI board)


This add-on consists of a few key parts:
  • Dual power supply with two outputs: 8.4V for IR LEDs and 5V for everything else
  • Ambient light level measurement with CdS cell on A/D converter of PIC12F675 so that the lights don't turn on during the daytime (for power saving feature - we must think green)
  • Sharp IS471F obstacle detection sensor with two transmitting IR LEDs, plus an additional IR focus lens for longer range
  • Third IR LED for RC5 code transmission for "remote controller" emulation by the PIC
How does it work
As I mentioned before, this is an add-on or a hack to my Dual Channel IR Remote Control (IR Remote Switch) project and after reading the description of that project it is clear that for it's operation IR remote controller is required. No problem here since we can emulate RC5 remote controller with PIC and one IR LED. With this PIC we need to send IR codes for ON and SLEEP functions on every obstacle detection so that the IR Remote Switch turns the lights ON and sets them to SLEEP - meaning that they will turn off in about 1-2 minutes. That's about all that this device does, besides measuring ambient light level and it also has a button to send 5 IR codes for programming the IR remote switch.

Setting up communication between these two IR devices
After putting this whole thing together make sure that the RC5 IR LED is pointed to the IR Remote Switch's TSOP receiver. Next put IR Remote Switch to programming mode, and press the Sw1 button on this device. Now IR LED will start to send 5 IR RC5 codes that the IR Remote Switch will learn. Those codes are for channel A - ON and SLEEP.
Circuit schematics


Two pots to set
In the schematics you can see two potentiometers. One is for setting the range of IR obstacle detection (VR2) and the other one is for the ambient light level (VR1). You must set this light level pot so that the device thinks it is nighttime even if/when the lights in the hallway are ON. I was lucky with this because CdS cell can recognize this variation in light level. There is also a software threshold when switching from nighttime to daytime that is 4 minutes long. This is enough time to trigger the two RC5 code sending again when the door closes, even when the lights turn on after opening the door for the first time (the IS471F sensor sends the trigger signal twice every time, once the door opens and the other time when they close - mostly quickly after opening them).

Optics for obstacle detection sensor
Here we have two transmitting IR LEDs and IR focus/filter lens on the IS471F receiving sensor. This combination enables more range especially with the external more-powered supply for the IR LEDs.
Optics arrangement (note that IR LEDs are actually angled a bit - not shown in the picture)
IR optics on PCB along with the CdS cell, button, RC5 IR LED, red system LED and trim pots
The other side of the user interface PCB (IR optics and the rest)
PCB with optics and user interface mounted in the fuse-box cover located above the door
This is pointing DOWN towards the obstacle to be detected (the door)


User interface
Here is the "user interface" with all gizmos sticking out of it explained.
User interface - explained (I got a little carried away while drilling the big hole)
Controller and PSU PCB
The PIC microcontroller does all the hard work, it emulates remote controller by sending some custom RC5 codes, measures ambient light level and decides whether it is day or night and receives trigger-signal from the IS471F sensor. On this PCB there is a power supply unit with two voltage outputs. One is unregulated and comes directly from the bridge rectifier. It's value is around 8.4V DC and comes from 6V AC multiplied by square root of two (that's the rule when we rectify from AC to DC). We need this higher voltage to run those IR LEDs for the obstacle sensor and this way we get more power from them - hence more range. The other voltage source is regulated with LM78L05 down to 5V.
PCB with dual output power supply and PIC
Completed setup inside the fuse-box cover
Now when I come home at night - the lights turn on immediately after I started opening the door AND when I leave home I don't need to turn them off because they will turn off automatically!

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Sony XPERIA Z1 C6903 - Android 4.4.4 - firmware 14.4.A.0.108 ROOT

Sony XPERIA Z1 is Sony Mobile flagship for 2013. This phone has large fullHD Triluminos display, powerfull quadcore CPU from Qualcomm, 2 GB RAM or 20,7 megapixel camera. Sony XPERIA Z1 is also water resistance. Below you can find the latest firmware for the phone and also three tutorials/manuals - how to unlock the bootloader, how to relock the bootloader and how to backup the original firmware customization.

First of all one important thing - before you start to do anything with your phone, do the backup of your personal data. It is only for your safety in case that something goes wrong or any mistake happens. In that case you can use the backup to restore the data and try to do everything once again. Each tutorial has been done many times to verify its propriety, so just read carefully all instructions and continue step by step. For each of Sony (Ericsson) XPERIA smartphones we will provide a manual consisting of 4, 5 or 6 „HOW TO“ chapters. Our tutorials will be of course updated every time when Sony Mobile publishes anything new, affecting any of our topics. All important files have been stored on Google Drive, so there should be no problem with downloading. The major part of every file has been created by myself and every file has been tested on the corresponding phone. In this guideline related to the Sony XPERIA Z Ultra you can find some photos and videos showing how to proceed, but the most important thing are the below written manuals. All referenced files are determined for Sony XPERIA Z1 C6903. So, what can you expect in terms of mentioned manuals / tutorials?


It is following 6 guidelines showing HOW TO:
1. how to install the newest Android 4.4.4 for your phone (for Sony XPERIA Z1 C6903 it is currently the 14.4.A.0.108 firmware)
2. how to install the newest Android 4.3 for your phone (for Sony XPERIA Z1 C6903 it is currently the 14.2.A.1.136 firmware)
3. how to install the newest Android 4.2.2 for your phone (for Sony XPERIA Z1 C6903 it is currently the 14.1.G.2.257 firmware)
4. how to backup your original firmware customization (it is important in case you must send your phone to service)
5. how to unlock the bootloader (in case you want to install the custom kernels with recovery menu and much more)
6. how to relock bootloader on your phone


1. how to install the newest Android 4.4.4 for Sony XPERIA Z1 C6903
a) first of all, check your firmware version (if you already have the newest one, you do not need this tutorial)
b) download and install latest Flashtool from here (mirrors One Drive or Mega)
c) download also latest Android 4.4.4 (mirrors Google Drive or Mega) for Sony XPERIA Z1
d) paste the ftf file downloaded in step c) to folder „Firmware“ included in the XPERIA Flashtool
e) open the XPERIA Flashtool, click on flash and choose downloaded firmware, than click ok. Important - if you do not want to delete any data of your phone, just uncheck flashing userdata.sin file. All data will remain in your phone, but sometimes it can cause additional troubles. So it is better (and I recommend that) to do the backup of your personal data, than proceed with clean instalation and then restore your personal data.
f) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button
g) after few minutes all is done and your phone gets the new firmware


2. how to install the newest Android 4.3 for Sony XPERIA Z1 C6903
a) first of all, check your firmware version (if you already have the newest one, you do not need this tutorial)
b) download and install latest Flashtool from here (mirrors One Drive or Mega)
c) download also latest Android 4.3 (mirrors Google Drive or Mega) for Sony XPERIA Z1
d) paste the ftf file downloaded in step c) to folder „Firmware“ included in the XPERIA Flashtool
e) open the XPERIA Flashtool, click on flash and choose downloaded firmware, than click ok. Important - if you do not want to delete any data of your phone, just uncheck flashing userdata.sin file. All data will remain in your phone, but sometimes it can cause additional troubles. So it is better (and I recommend that) to do the backup of your personal data, than proceed with clean instalation and then restore your personal data.
f) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button
g) after few minutes all is done and your phone gets the new firmware


3. how to install the newest Android 4.2.2 for Sony XPERIA Z1 C6903
a) first of all, check your firmware version (if you already have the newest one, you do not need this tutorial)
b) download and install latest Flashtool from here (mirrors One Drive or Mega)
c) download also latest Android 4.2.2 (mirror) for Sony XPERIA Z1
d) paste the ftf file downloaded in step c) to folder „Firmware“ included in the XPERIA Flashtool
e) open the XPERIA Flashtool, click on flash and choose downloaded firmware, than click ok. Important - if you do not want to delete any data of your phone, just uncheck flashing userdata.sin file. All data will remain in your phone, but sometimes it can cause additional troubles. So it is better (and I recommend that) to do the backup of your personal data, than proceed with clean instalation and then restore your personal data.
f) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button
g) after few minutes all is done and your phone gets the new firmware


4. how to backup your original firmware customization
a) if you do not want to lose warranty of your phone, first thing you have to do is to backup your original customization
b) download Sony Update Service (SUS) and reinstall firmware of your phone (backup your data first)
c) after that, go to SUS folder in Program Files and search for folder db/some Number/blob_fs, there you find 3 files, which names start FILE
d) download and install latest Flashtool from here (mirrors One Drive or Mega)
e) paste the three files, which names start FILE, from blob_fs folder to folder „Firmware“ included in the XPERIA Flashtool
f) open the Flashtool, click on Advanced, choose decrypt files and put all three files from blob_fs folder to the right columm
g) click ok and after approx. one minute a pop up Window will appear via Flashtool
h) mark all files and transfer them to the right column, than fill in a box in the right upper corner (fill in what you want, it is just for you)
i) now click ok and Flashtool will create backup of your original firmware customization, that you can anytime flash to your phone


5. how to unlock your bootloader
a) download and install latest Flashtool from here (mirrors One Drive or Mega)
b) start Flashtool and click on BLU button on the top
c) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button
d) click on get unlock key button, it will switch you to Sony Mobile website, here complete all boxes
e) copy IMEI form Flashtool to Sony Mobile site, than you will get unlock code to your mailbox
f) copy unlock key to Flashtool window and than click unlock
g) connect phone with holding volume up button when Flashtool shows pop up window
h) wait to unlock finish


6. how to relock your bootloader
a) download and install latest Flashtool from here (mirrors One Drive or Mega)
b) start Flashtool and click on BLU button on the top
c) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button
d) just click on relock button and your bootloader is locked for now


IF U Need firmware from Other site Clip Here.

Rooting Guild

  1. download the kernel package
  2. save it to the sdcard
  3. reboot into recovery
  4. flash the kernel package using recovery
  5. reboot from recovery into system
  6. the device should now start booting
  7. enjoy!
[ how to flash this kernel ] (via fastboot)

download the kernel image save the boot.img to the folder containing fastboot binary flash the boot.img using fastboot:
Code:
fastboot flash boot boot.img
reboot from fastboot
Code:
fastboot reboot
the device should now start booting enjoy! Advance Kernel

Advance Stock Kernel with Recovery v05 (FW:14.4.A.0.108)
{RECOVERY FLASHABLE}
{MIRROR}
MD5HASH: 5a7d01df6bee76d3355fedddb306aaa4


For Zawgyi Myanmar Fonts

Download Here

SonyV4.3_mmFont_installer

SonyV4.3_mmFont_Uninstaller

And Put it your Phone Storage.Then press and Off power your Phone Wait for the 30 Seconds. After On Back your Phone and press Volume Up (+) and choose Above link Zip files.

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Nokia Asha 501 RM-900 Flash File Latest Free Download

Click below to download the Nokia Asha 501 RM-900 flash file: DOWNLOAD LINK:

RM900_059R363_14.0.4_070.vpl (4.62 KB)

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iPhone-5 Charging Problem 100% ok

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Sony XPERIA M2 D2303 - Android 4.3 - firmware 18.0.C.1.13

Sony XPERIA M2 is new model in Sony Mobile portfolio for 2014. It has large 4,8 inch display, 2300 mAh battery, powerfull quadcore CPU from Qualcomm and 1 GB RAM. Phone will be upgraded to Android 4.4.2 KitKat. Below you can find the latest firmware for the phone and also three tutorials/manuals - how to unlock the bootloader, how to relock the bootloader and how to backup the original firmware customization.

First of all one important thing - before you start to do anything with your phone, do the backup of your personal data. It is only for your safety in case that something goes wrong or any mistake happens. In that case you can use the backup to restore the data and try to do everything once again. Each tutorial has been done many times to verify its propriety, so just read carefully all instructions and continue step by step. For each of Sony (Ericsson) XPERIA smartphones we will provide a manual consisting of 4, 5 or 6 „HOW TO“ chapters. Our tutorials will be of course updated every time when Sony Mobile publishes anything new, affecting any of our topics. All important files have been stored on Google Drive, so there should be no problem with downloading. The major part of every file has been created by myself and every file has been tested on the corresponding phone. All referenced files are determined for Sony XPERIA M2 D2303. So, what can you expect in terms of mentioned manuals / tutorials?


It is following 4 guidelines showing HOW TO:

1. how to install the newest Android 4.3 (for Sony XPERIA M2 D2303 it is currently the 18.0.C.1.13 firmware)

2. how to backup your original firmware customization (it is important in case you must send your phone to service)

3. how to unlock the bootloader (in case you want to install the custom kernels with recovery menu and much more)

4. how to relock bootloader on your phone

1. how to install the newest Android 4.3 for Sony XPERIA M2 D2303

a) first of all, check your firmware version (if you already have the newest one, you do not need this tutorial)

b) download and install latest Flashtool from here (mirrors Google Drive or Mega)

c) download also latest Android 4.3 (mirrors Google Drive or Mega) for Sony XPERIA M2

d) paste the ftf file downloaded in step c) to folder „Firmware“ included in the XPERIA Flashtool

e) open the XPERIA Flashtool, click on flash and choose downloaded firmware, than click ok. Important - if you do not want to delete any data of your phone, just uncheck flashing userdata.sin file. All data will remain in your phone, but sometimes it can cause additional troubles. So it is better (and I recommend that) to do the backup of your personal data, than proceed with clean instalation and then restore your personal data.

f) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button

g) after few minutes all is done and your phone gets the new firmware.

2. how to backup your original firmware customization

a) if you do not want to lose warranty of your phone, first thing you have to do is to backup your original customization

b) download Sony Update Service (SUS) and reinstall firmware of your phone (backup your data first)

c) after that, go to SUS folder in Program Files and search for folder db/some Number/blob_fs, there you find 3 files, which names start FILE

d) download and install latest Flashtool from here (mirrors Google Drive or Mega)

e) paste the three files, which names start FILE, from blob_fs folder to folder „Firmware“ included in the XPERIA Flashtool

f) open the Flashtool, click on Advanced, choose decrypt files and put all three files from blob_fs folder to the right columm

g) click ok and after approx. one minute a pop up Window will appear via Flashtool

h) mark all files and transfer them to the right column, than fill in a box in the right upper corner (fill in what you want, it is just for you)

i) now click ok and Flashtool will create backup of your original firmware customization, that you can anytime flash to your phone


3. how to unlock your bootloader

a) download and install latest Flashtool from here (mirrors Google Drive or Mega)

b) start Flashtool and click on BLU button on the top

c) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button

d) click on get unlock key button, it will switch you to Sony Mobile website, here complete all boxes

e) copy IMEI form Flashtool to Sony Mobile site, than you will get unlock code to your mailbox

f) copy unlock key to Flashtool window and than click unlock

g) connect phone with holding volume up button when Flashtool shows pop up window

h) wait to unlock finish


4. how to relock your bootloader

a) download and install latest Flashtool from here (mirrors Google Drive or Mega)

b) start Flashtool and click on BLU button on the top

c) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button

d) just click on relock button and your bootloader is locked for now



Rooting Guide

Mr. Awesome DooMLoRD, XDA recognized developer has released a working root procedure for the Sony Xperia M2 running on Android 4.3 Jelly Bean on Firmware 18.0.A.1.30 – v01. You can easily root your phone and install ClockworkMod recovery. Follow the step-by-step guide explained below to get rooted

Warning!! Root at your own risk. Android Root Central and the developer takes no responsibility, if in case you damage your device. Note that the tutorial has been tested and is confirmed working on the Sony Xperia M2

Before Rooting your Xperia M2, It is recommended that you Backup all important data stored on your phone!!


Requirements:
  • Rooting guide is only for the Sony Xperia M2 running on Android 4.3 Jelly Bean.
  • Make sure that you’ve already Unlocked Bootloader on your phone. Unlock Bootloader Here
  • Install USB drivers on your PC.
  • Go to Settings > Developers Options and enable USB debugging.
  • Charge your phone battery up to 6o% in order to avoid uncertain shutdown during the rooting process.
  • Carefully read and follow the instructions

Download the required Files:

Procedure: Installing CWM Recovery
STEP 1: First download the kernel image from the above download links.

STEP 2: Extract the Fastboot folder (Android.rar) and Copy the kernel image file. (Rename it to boot)
STEP 3: Within the folder, Hold the SHIFT Key + Right click on the blank area and select the option “Open command window here”.
STEP 4: Now boot your Xperia M2 to recovery mode:
  • Power off your phone
  • Turn it again and when you see the Sony boot logo, keep pressing the Volume Down key.
  • Connect it to PC via the USB cable.
STEP 5: In the command window type the following to flash the kernel:
fastboot flash boot boot.img
STEP 6: When flashed, type this command to reboot your phone:
fastboot reboot 
You’ve now successfully installed CWM Recovery. To get root Xperia M2 follow the further instructions below. Procedure: Rooting Sony Xperia M2

STEP 1: First download the SuperSU zip file from the above download link and Copy it to your SDcard.<

STEP 2: Reboot your phone into Recovery Mode as you did in the early steps.

STEP 3: Choose the option “Install Zip” > “Install Zip from SDcard” and browse SuperSU zip file.
STEP 4: Confirm to flash.

STEP 5: When done, navigate back to the menu and choose the option “Reboot system now”.

Cheers!! You’ve now safely and successfully got root access as well as installed CWM recovery. You can easily install Custom ROMs, Tweaks and mods on your phone to improve its overall performance. Do not forget to leave your feedback and share your experience. If you’re having queries or confused at any step, feel free to ask for further support and assistance. For more Rooting Guides keep visiting.

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Mini Audio Transmitter

In this instructable I'm going to show you how to build your own portable audio transmitter. This transmits FM waves so you could easily get the signals on your mobile phone, radios, etc. As the name and the picture indicates it is very small and is approximately the size of a 9v battery clip.

This transmitter is like the ones in the movies which are used to spy on people or try to record conversations, well don't use this this to spy on anyone, its just for educational purpose only.

What does this do?
  • Well all this is a FM transmitter so you could start your own mini FM station.
I'm going to build a mini FM receiver soon, to go with the mini FM transmitter

How does this work?

Well all of us have heard of "frequency modulation", most commonly known as "FM", this circuit works on the very same principal to transmit audio signals captured by the microphone. This circuit uses BC547 transistor to amplify the signal and then frequency modulate it. Since it is tiny and powered with just 9v the signal range is limited to only 15m.

If you like my project you can vote for me in the battery powered contest.

OK now enough of the talking and let's start building.

Step 1: Tools and Components

Like always lets start with getting all the parts, the list is quite simple all you need is

Components
  • BC547 Transistor
  • An microphone
  • A variable capacitor 47pf
  • An Inductor (see steps for description)
  • 4.7k Resistor
  • 330ohm resistor
  • 1n capacitor (102)
  • 10p capacitor
  • 9V battery
  • LED(optional)
Tools
  • Soldering Iron
  • An FM receiver (any mobile phone)

Step 2: Components
I got almost all of the components from a pile of old PCBs I had in an old forgotten box. All I had to get was the BC547 and the electret microphone. Actually I did find the BC547 in an old PCB but i was not sure if it would work. It looked quite burnt to me. The old PCBs had many components resistors, crystals, diodes, etc. I may use them some day and for know back in the box.

I had to de-solder the parts of the old board, for those who don't know how to solder and de-solder there is a bunch of instructables that describe how to do this and learning to solder is not a hard task.

Step 3: PCB
First of all lets start with cutting up a PCB to the required size. The size to compare is a 9v battery clip, it might look quite small in the beginning but don't worry it would hold all the components just fine. Use a sand paper for smoothing the sides of the PCB and to clear out any rough edges.

Make sure to get a PCB with big holes as the variable capacitor pins won't go in the standard size holes.

Step 4: Microphone

You can get the microphone at a local hardware store. And be sure to get some male pins to hold the microphone in place refer the picture as to how to solder the microphone in place.

Why not use some wires to hold the microphone?

I would not suggest wires as when you tape the circuit if the last few steps you would not get a clear audio. I tried it and got a lot of noise. I got lesser noise when I used the male pins soldered to the microphone.

Step 5: Circuit

Once you're done with the PCB and know where and how to solder the microphone now it's time to complete the rest of the circuit. Follow the circuit above and solder all of the components. Make sure not to leave any space between any of the components if you need to get the circuit small. For the inductor use 0.5mm wire and 8 turns, with each turn with a diameter of 6mm.

And for the antenna just use a thin 5cm long wire. For more stability you could center tap the coil and solder the antenna to the center tap.

Also If you notice the circuit has a LED in it, it is used to show when the circuit is functional. I did not add the LED in my circuit because it was draining my battery faster.

Step 6: Taping Time

Once you got the circuit like the one in the above picture, it's time to cover it with tape. I used wiring tape to cover the whole circuit except the microphone and the variable capacitor. This is an important step as when you proceed to the next step, where you tune to the required bandwidth. Touching the circuit (mainly the coil) with your fingers would lead to severe noise.

You could also use a heat sink instead of tape, I used tape because I wanted to experiment withe circuit so I did not want it to be permanent.

Step 7: Tuning to the required bandwidth

Now it's time to tune the circuit to a required bandwidth, you could do this in two ways.

Use your mobile phone to find the signal Manually tune the variable capacitor to match a frequency

The first step is recommended all you have to do is power the circuit and turn on auto find bands on your mobile. Your mobile would scan for channels and all you have to do is look for your transmitter (play some music in front of the transmitter) on that list.

The second method is time consuming, in this method you have to turn on your radio and the circuit. Keep the radio at a specific channel, and then tune the variable capacitor extremely slowly. When you hear stuff on the radio maybe a song that you are playing stop and the bandwidth on the radio is the required bandwidth.

Step 8: Re-Chargeable version

After using the 9v battery circuit for some time I thought of replacing the battery with rechargeable Li-ion batteries. If you have viewed my previous instructables you would have seen that I use these batteries a lot.

The rechargeable batteries provide longer transmission than the common 9v battery.

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