Showing posts with label Electronics. Show all posts
Showing posts with label Electronics. Show all posts

Thursday, July 22, 2010

How to repair RAM Cards (Memory Card)

How to Repair (Damaged/Broken) RAM Memory


RAM ....?


To repair or troubleshoot a memory module you should have to identify what are the problems in your memory. Example: Memory dump or Shorted Ram chip in Ram Card. Some failling Ram Chips make PC restarting or corrupt data during accessing hard disk drive. To solve this problems you can use memory testing software. If RAM card shorted or EEPROM damaged or it erased, then find same ram card or copy EEPROM or replace damaged chip.
Most RAM cards use 24C02 series EEPROMs. with I2C memory reader you can copy or read data in SDRAM DDRAM Cards. But beware when using a multimeter with 3V analog and don't use x1 ohms range with higher mA

If Some ICs are shorted, find same type of RAM chips and replace with a working one.
Here's some of work I did my own.
  • Find the faulty chip

  • After Desoldering

  • Before cleaning up the PCB

  • After cleaning up the PCB

  • Find a similar chip

Solder the corner 4-pins and after solder all pins using hot air

After replacing the CHIP

Monday, May 10, 2010

Capacitor and Inductor (L/C) meter

Capacitor and Inductor Meter
Low cost L/C meter



Using L/C meter it is easy to troubleshoot faults in RF circuit. I had a problem with testing pF value in a clock circuit and oscillators. So I made this and it is very accurate and easy to build.

I replaced the 82uH inductor with 100uH and it works fine. I couldn't find Reed Relay and I replaced it with a 12v Relay with separate 12V regulator to power it.

To get a better performance, use sort wire to L/C connectors.




LC Meter's Inductance Measurement Ranges
10nH - 1000nH1uH -1000nH
1mH -100mH

LC Meter's Capacitance Measurement Ranges:
0.1pF - 1000pF
1nF - 900nF

Expected Accuracy is +/- 1% of reading +/- 0.1pF or +/- 10nH

Main part is PIC 16F84 and use JDM programmer.

Download Source code for 16F84A




Saturday, April 17, 2010

How to Build a Simple Card Reader

SIM/DVB-Cards and any type of Plastic Smart card Reader (Phoenix Interface)

        How to read SIM card or DVB cards?
  1. To read SIM cards you should make a Stable Clock Circuit
  2. TX/Rx (Data In / Out) In put Output Data
  3. Make Serial to stable Level converter (12v = 5V)
  4. Some Software .Depend with what you want (SIM / DVB)
Home made Smart card / SIM Card Reader
Generic Phoenix Smart card / Sim card Reader
I made this reader and it didn't work. There was a trouble in the clocking circuit so I replaced the Clock circuit stage with stable generic clock circuit and it finally worked.

This is the Same circuit with stable clocking stage

Use one of these Crystals 3.579MHz, 4.000MHz, 6.000MHz or 7.000MHz
  • All type of SIM cards fully works without any trouble
  • Irdeto Zeta card 5.04/5.03 works with 6.000MHz Crystal
  • Works with Fausto v1.42
Don't worry about my WebCAM More About SIM and Smart Card SIM Cards Smart Cards

Thursday, May 28, 2009

How Make Universal Infrared Remote Control

Turn your PC into a Universal Infrared Remote Control



This is Pronto 9600 from Philips. They say Best-in-class IR learning and sending performance and are largest Infrared Remote Control data base. It can control a large number of devices. It has the best graphics and you can customize buttons and graphical view and IR codes using their Pronto Studio. www.pronto.philips.com

Make your own!

Make your own universal Infarared Remote controller device that also have these capabilities. With your Notebook or PC you can make a Serial interface based IR receiver and IR Transmitter and learn IR signal codes and send it back.

You can make this simple IR Transmitter and Receiver circuits to make a Programmable Universal Infrared Remote control.


Simple Universal Infrared Receiver for Serial interface

Simple Universal Infrared Transmmeter for serial interface

How to Configure your circuit with winLIRC

IrCode from www.lirc.org

How to control a PC with your IR Receiver





Control your PC with an IR remote

Control your PC with an IR remote controller like of TV , DVD, VCR, SAT, etc...






Every manufacturer (Samsung, Sanyo, Sony. Hitachi, Philips etc..) use different IR code to communicate with IR devices. For an example :- Receiver determines that you pressed "Power" button by identifying the control as 0001 and "Vol +" 0010. That code contains with binary numbers (it have simply 1 and 0 :) ).

Controlling PC with an IR remote

You can make a simple serial port IR receiver to receive signals from any IR consumer remote control and learn various signals from many remote controllers. After you learned IR signals from your remote control, you can define what should happen when you press Power button on your remote. You can set up your remote controller to start a window or play songs or even mouse movement ( Your IR remote controller as an IR mouse). (Or you can buy remote with its receiver that comes with Windows XP Media Centre Edition 2005 by making Microsoft rich)

IR receiver for serial port (Circuit Diagram)

Software configuration for your Circuit

Using serial port IR receiver you can make and collect IR codes for you own Universal IR Remote controller data base. You can Backup and Restore (Receive and Transmit) IR codes from your remote controller. If you cannot find your remote controller in the future you can get that IR code to make a remote controller using PIC.

Make a Programmable Universal IR Remote Controller with your IR Receiver

How to configure your circuit with winLIRC


Wednesday, May 27, 2009

Standard DB9 and DB25 Pinouts

Name        25-pin         9-pin
---------------------------------------------------------
TxD 2 3 transmit data
RxD 3 2 receive data
RTS 4 7 request to send (power)
CTS 5 8 clear to send
DSR 6 6 data set ready
GND 7 5 ground
DCD 8 1 data carrier detect(signal)
DTR 20 4 data terminal ready

IR Transmitter for Serial Interface

How to make IR Transmitter for your serial interface ( RS232 , COM)

What IR range do you want to send using your serial port? You should select IR Emitting diode with your IR range. If you want to control your CD players, DVD players, TVs, VCRs, Cable Boxes, Receivers, Tape Decks, DVRs, home automation, etc. You can use consumer standard IR devices like 510E850C , TIL31 or you can try with your old Remote control Infrared LED. Use this simple circuit to connect your IR LED to serial port.



IC1 = 78L05

Q1 = 2N2222
or try with C945

D1 = 1N4148

R1 = 1K

R2 = 47Ω

LED1 = IR LED
510E850C
TIL31





IR codes for Samsung SVACI-202

Every IR remote have unique IR signals in hexadecimal codes. I have a device of this model with out a remote. And more to my dismay it was locked(by master code) and can't unlock it without a remote controller. If anyone have this device "with a working remote" please send its IR codes to info@zipwaves.tk.

You can get IR codes of any remote using Serial Port based IR Receiver. Here are the instructions to make a IR receiver. You can use this device to control your PC with any remote controller! or you can turn your PC into a Universal Remote Controller with Serial Port based IR Transmitter .....................................................

Use this software to create your IR codes, learn signals of any IR remote controller and imitate that signal. http://www.lirc.org

Tuesday, May 26, 2009

IR Receiver for serial interface

Making a simple IR receiver for serial port (RS232,COM)

For receiving infrared signals you have to get a photo module. First you have to determine what range of infrared signal you want to receive with your serial port.Examples for equipment with consumer standard IR devices are CD players, DVD players, TVs, VCRs, Cable Boxes, Receivers, Tape Decks, DVRs, home automation, etc.

This simple circuit receives IR signals using TSOP 1738 photo module. You can use any IR module for your choice. TSOP 17-XX, SFH 506-XX series is a compatible module to receive IR remote control signals from COM ports on CD player, DVD player, TV, VCR, Cable Box, Receiver, Tape Deck, DVR, home automation, etc.

Photo modules TSOP 1730, TSOP1733,TSOP 1736, TSOP 1737, TSOP 1738, TSOP 1740, TSOP 1756 or you can try your old broken DVD Player!, VCR, TV or anything that have an IR remote controller. It should have 3 pins and 5V. Study your the photo module to know how to attach that device and use that pin connections this circuit.
IC1 = 78L05

IC2 = TSOP 1738
(IR Module)

SFH 506-XX

TSOP 17-XX


D1 = 1N4148


R1 = 4k7


C1 = 4.7uf