Stereo Gain Audio Trim Control Circuit

Audio Gain Control With Digital Potentiometers

Stereo Gain Audio Trim Control Circuit

This circuit using the MAX5160L digital pot in a divider chain supplying the MAX4252 op amp with some positive feedback in addition to the usual negative feedback via the 100K and 50K resistors. The gain of this circuit can be shown to be:

AV = (1-Kn)/(Kp-Kn)

where Kn is the negative feedback fraction, Kp the positive feedback fractions (for the example in Figure 4, Kn = 100K/(100K + 50K) or 2/3, and Kp is variable).

When the MAX5160L wiper is positioned at the VREF terminal, the gain of the circuit is -0.5V/V, as there is no positive feedback contribution. When the wiper is at mid scale, Kp = 0.5, and the gain is now -2V/V. Hence, by using those 17 positions between VREF and midscale the gain can be varied over a ±6dB range. The 15 unused positions have been traded off for repeatability, as the gain value does not depend upon the digital pot resistance tolerance, as did the circuit of Figure 1. The gain tolerance is now only limited by the ±1% 100K/50K resistors, and the INL/DNL error of the MAX5160L (±4.6% max.).

An interesting point to note, the limit for stability in this circuit is reached when Kp ≥ 2/3, when the positive feedback fraction meets or exceeds the negative. The host processor controlling the MAX5160L should therefore prevent this situation occurring.

The circuit in Figure 5 shows an obvious appraoch to a 'traditional' style volume control using digital pots. All codes are valid, with settings ranging from 0dB to full attenuation. Table 1 shows the calculated attenuations based on the MAX5160L's 32 steps.

Nestbox Solar Powered Wireless CCTV Camera Circuit

Below is the circuit used to power the CCTV camera, provide lighting inside the nestbox, and charge batteries from a PV solar panel.
Circuit diagram for CCTV powered by Solar Panel with Battery Backup


D1 is a Schottky Diode used to prevent battery charge escaping through the solar panel at night. Something like a 1N5817 (1 Amp 20 Volt diode) will do the job and it has a very low voltage drop of under 0.45 Volts. D2 and D3 are ultrabright LEDs used to illuminate the inside of the nestbox. R3 and R4 are resistors chosen (400+ Ohms) to ensure that no more than 30mA of current gets to the sensitive LEDs, with R5 (a 10k variable resistor) used to increase the resistance and therefore dim the LED s if they are too bright.The LM317T is a voltage regulator * used to bring the voltage of the solar panel and batteries down to just over 8 volts using resistors R1 (270 Ohm) and R2 (1500 Ohm) to set this value. K is the wireless CCTV camera. A switch (not labelled) is used to manually turn the camera on and off as required.

Extra - Low battery indicator

The extra circuit supplied is to check the battery condition.
Low battery voltage (below than ~6.9V) will show "RED" light up.
Else will show "GREEN" LED light up.
The basic, if there is a small amount of current go through the zener (reverse bias),
the first transistor (left) will be turned on making the "GREEN" LED turn on.
Other than that the second transistor (right) will be turned on and "RED" LED will light up.

Modification - Add in buzzer

You add in buzzer to the circuit to make it give an audible alarm.
The best is to alert us whenever the cable under test is not "GOOD".
So, adding a resistor, transistor and a buzzer/beeper to the last NAND (near "GOOD" LED) will do the job.
Use your own creativity for this. :-).

Simple Cable Tester

Simple DIY Cable Continuity Tester

How to use

This simple cable tester can be used to check 2 wire cable such as coax cable, telephone cable, audio cable and etc.
Power the circuit using 9V battery.
Plug in the cable and push "TEST" button.
The dummy resistor is connected to the end of the cable which has 75ohm resistor inside.
The tester will show only 3 conditions, "SHORT", "OPEN" and "GOOD".

How it works

The method is to check resistance of the dummy resistor at the "Terminator".
The idea is simple.
Imagine there is a short circuit cable under testing.
The wire will act as nearly zero ohm resistor thus making the voltage divider near the dummy resistor to divide the 9V into 4.5V.
Calculate it your self [ ( 1k / ( 1k + 1k ) ) * 9V = 4.5V ].
4.5V is below than the lower "Comparator" limit (Vref 4.57V).
It will trigger the lower "Comparator" and make "Short" LED to light up.
Now for the open circuit cable.
Assuming the open circuit cable has an infinite ohm.
Voltage divider near the dummy resistor will give 9V.
This is more than the upper "Comparator" limit (VRef 4.8V) and will trigger make "Open" LED light up.
Other than that (both lower and upper "Comparator" didn't trigger) the "GOOD" LED will light up.
For the op-amp, I'm using JRC4558 dual op-amp since I have it in my stock.
You may use 741 op-amp or other multi-purpose op-amp.
Learn more about op-amp here

Vref tuning

Before turning on the circuit (power it up),
tune the potentiometer so that it will give the correct voltage reference to the "Comparator"s.

• Upper "Comparator" = 4.8V
• Lower "Comparator" = 4.57V

Sony Ericsson Xperia ™ mini pro

Ergonomic keyboard and start typing. Widget Type & Send allows all messages handled in one place. Live life with people.



HD Capture with a sharp volley. Shoot the player with a 5 megapixel auto focus camera. The mood dimmed? Flash photo captures it pretty details. Now show mahakaryamu with high contrast on the screen Reality Display with Mobile BRAVIA ® Engine.

Life looks brighter through the touch screen Android from scratch resistant glass. Do not forget anyone's birthday. Fun at once on the Xperia ™ mini pro. Synchronize email and calendar while ago with Exchange ActiveSync ®.



Specification:



Size 92.0 × 53.0 × 18.0 mm / 3.6 × 2.1 × 0.7 inch Available colors Black, White, Pink, Turquoise

Weight 136.0 gr / 4.8 oz Memory Phone memory up to 400MB

microSD ™ support up to 32GB

RAM: 512MB

Memory card included: 2 GB microSD ™



Actual free memory may vary due to phone pre-configuration

Screen 320 x 480 pixels (HVGA) / 16,777,216 color TFT

Battery Performance



Battery performance may vary depending on network conditions, configuration and phone usage.

Talk time: Standby time: Video call:

GSM / GPRS / EDGE 850/900/1800/1900 5 hrs 40 min 331 hours x

UMTS / HSPA 900/2100 5 hrs 25 min 340 hours x

UMTS HSPA 800/1900/2100 5 hrs 25 min 340 hours x



GreenHeart ™



-Eco-smart packaging



The phone is packed in smaller boxes and lighter to reduce the environmental effects in terms of transport and conserve precious natural resources.



-GreenHeart ™ Headset



Headset environmentally friendly, most are made from recycled plastic.



-GreenHeart ™ Charger



Battery chargers obey the V Energy Star level and has a standby power loss is less than 30mW. This means reduced power consumption.



-E-Manual



Save paper. User guide is replaced by an electronic version in the phone.



Camera



-Type the flash / lamp - LED



If the lighting conditions are bad, your picture can still look good.



-Video recording



Capture the action as it happens.



-Video light



Add light when shooting video.



-Touch Focus



Touch the screen to specify what areas of focus.



-Smile Shutter ™



Let alone a camera that automatically shoot when a subject threw a smile.



-Detection smile



Let alone a camera that automatically shoot when a subject threw a smile.



-Picture blogging



Pictures taken your phone will be displayed online.



-HD video recording (720p)



Record High Definition video with a simple touch of a button.



-Geo Tagging



Your photos can be tagged with the following information about where the photo was taken.



-Face recognition



The phone automatically recognizes up to five faces in your pictures.



-Face detection



Your phone automatically sets the focus on faces in your pictures.



-Auto Focus



Auto focus for optimal clarity.



-Aperture f / 2.6



Allows more light reaching the image sensor.



-Digital zoom - up to 8x



Closer to your subject.



-Camera - 5 megapixel



Capture and share special moments.



Music



-XLOUD ™ Experience



Maximizing, speakers blaring sound thanks to the audio engine filter technology Sony xLOUD.



-TrackID ™ music recognition



Record a song for a few seconds and get information on the song title, artist name and album sent to your phone within seconds.



-Sony Ericsson music player



Enjoy your favorite music sorted by artist, album and track. Shake feature and smart playlists.



-PlayNow ™



Download music and games to your phone.



-Music tones



Use the original artist recordings as ringtones.



-Bluetooth ™ stereo (A2DP)



Music from phone to headset over a wireless connection.



Internet



-Web browsers - WebKit



Full Internet Browser with support for standard protocols, images and video.



-Google ™ Search



Find who searched with Google ™ search function.



-Google Voice Search



Use your voice to search on the web, or to launch a quick call to a friend.



--Bookmark



Quick access to your favorite websites.



Android ™ Market



Get applications and games - download it directly to your phone



Entertainment



-Radio - FM radio with RDS



Entertainment radio all the time.



-Radio - FM radio



Entertainment radio all the time.



-YouTube ™



Add your favorite YouTube ™ videos, or upload your own - easy access via YouTube ™ application.

-Video streaming



Watch videos on the go. No need storage space.



-Media



Media content in one place for quick and easy access.



-3D games



Enjoy a game full of color quality and steady.

Connectivity



-Google Maps ™ - With Street View



Find your way to your destination.



-Alignment - Exchange ActiveSync ® through client Moxier



Stay terselaras without barriers with Microsoft ® Exchange email server.



-WiFi ™ certified



Utilise high-speed Internet at Wi-Fi hotspots at airports ™ and other facilities.



-Navigation Wisepilot ™ bend per bend



-USB mass storage



Connect and move items between your computer and phone.



-Alignment via Google Sync



Use your Google account to sync contacts on your phone.



-Alignment through Facebook ™



Match friends up ™ with your phone contacts.



-Modem



Connect your computer to the Web using your phone wherever you are.



-Google Latitude ™



See the existence of your friends - and share your location with them.



-DLNA Certified ™



Connect wirelessly to other devices.



-Bluetooth ™ technology



Connect to other Bluetooth ™ devices wirelessly.



-aGPS



Based services utilizing GPS-powered location.



-3.5 mm audio jack



Sharing music via the extra jack. Use any headphones with a standard connector size of 3.5 mm.



Messaging



-Type & Send



Handle all your messaging directly from the screen porch.



-Text messaging (SMS)



Send text greetings anywhere in the world.



-Recorder



Make voice notes or record a voice clip to send in a message.



Predictive text input



Text messaging is quick and easy.



Picture messaging (MMS)



Multimedia messages in color.



Instant messaging



Online chat on the way



-Google Mail ™



With Gmail for mobile, you can send and receive emails wherever you are.



-Email



Check your email inbox wherever you are.



-Conversation



Tell me via SMS chat style.



-Communication



Twitter ™ - Integration ™ Timescape



Let the world know how you feel and what you think - say via tweet.



-Vibrating Alert



When your phone is in silent mode, you will know if there is an incoming call or message.



-Speakerphone



Hands-free convenience while on the call.



-Sony Ericsson Timescape ™



All your communications with one person in one place.



-Noise Shield



Filtering the sound around for your voice heard.



-Google Talk ™



Communication style chat with friends and family.



-Facebook ™ Application



Connect with friends on Facebook ™ via phone.



Design



-Four corner of the screen porch - custom icons



Quick access to favorite functions via four icons in the corner of the screen porch.



-Keyboard - QWERTY



Easily insert text



-Keyboard - QWERTY on-screen



Easily insert text



-Keyboard - 12 keys on the screen



Easily insert text



-Animated wallpaper



Moving pictures on screen style.



-Touch screen



Intuitive navigation - just touch the screen.



-Intelligent Keyboard



Instant access to relevant functions - just slide out the board ketiknya.



-Reality display with the BRAVIA ® Engine Mobile



Crystal-clear colors and sharp images.



-Picture wallpaper



Your favorite picture in standby.



-Auto rotate



Switching from vertical to horizontal mode by rotating the phone. Whatever your view will rotate to adjust.

Organizer



-Phone book



The information you need to keep in touch with friends and family.



-Notes



Digital records for things you need to remember.



-Infinite Keys



Only one press to find out all about your friends, or the artist info is needed.



-Google Calendar ™



Create, add and edit events Set reminders and notifications via cell phone.



-Flight mode



Disable the radio receivers and transmitters in your phone so you can safely use other functions.



-Calendar



Store names and set reminders.



-Calculator



Fully functional when you need it.



-Alarm clock



Set the alarm clock to ring at the time of your choice.



-Handwriting recognition



Write like you are using a pen. Your handwriting into digital text.



Check my other post : HOT!Electronic Music

Sony Ericsson Xperia ™ arc

Android phone touchscreen Xperia ™ arc - designed to look brave. Viewing pictures and videos in clear with color touch screen Android phone. Clear and clean on Reality Display 4.2 "with Sony's BRAVIA ® Engine Mobile. Enhanced by indentation. The phone has a Sony HD R Exmor ™ CMOS sensor for phones that lets you record high quality movies and still images in low light.





Specification:



Size 125.0 × 63.0 × 8.7 mm / 4.9 × 2.5 × 0.3 inch Available colors Midnight Blue, Misty Silver

Weight 117.0 gr / 4.1 oz Internal Phone Memory Storage: 1GB (free up to 320MB)

RAM: 512MB

Memory card slot: microSD ™, up to 32GB



Actual free memory may vary due to phone pre-configuration

Screen 854x480 pixels / 4.2 "color TFT 16,777,216

Battery Performance



Battery performance may vary depending on network conditions, configuration and phone usage.

Talk time: Standby time: Video call:

GSM / GPRS / EDGE 850/900/1800/1900 6 hours 55 min 430 hours x

UMTS / HSPA 800/850/1900/2100 7 hours 400 hours x

UMTS / HSPA 900/2100 7 hours 400 hours x



Please note that the compatibility of UMTS / HSPA vary by location.

Music Listening time: 31 hours



Music



-Sony Ericsson music player



Enjoy your favorite music sorted by artist, album and track. Shake feature and smart playlists.



-Music tones - MP3, AAC



Use the original artist recordings as ringtones.



-TrackID ™ music recognition



Record a song for a few seconds and get information on the song title, artist name and album sent to your phone within seconds.



-PlayNow ™



Download music and games to your phone.



-Bluetooth ™ stereo (A2DP)



Music from phone to headset over a wireless connection.



-Picture Album



Select a music CD albums by browsing pictures or other images



Internet



-Google Voice Search



Use your voice to search on the web, or to launch a quick call to a friend.



-Android ™ Market



Get applications and games - download it directly to your phone.



-Web browsers - WebKit



Full Internet Browser with support for standard protocols, images and video.



-Pan & zoom



Viewing a web page to suit your taste - get quick overview or perbesarkan details.



-Google ™ Search



Find who searched with Google ™ search function.



-Bookmark



Quick access to your favorite websites.



-Entertainment



Radio - FM radio with RDS



Entertainment radio all the time.



-YouTube ™



Add your favorite YouTube ™ videos, or upload your own - easy access via YouTube ™ application.



-Video Clip



Watch a video clip on your phone screen.



-Video streaming



Watch videos on the go. No need storage space.



-Mobile games



The game involves physical - turn, swing, move the phone to control the action.



-Media



Media content in one place for quick and easy access.



-3D games



Enjoy a game full of color quality and steady.



Connectivity-



-ANT + Technology



Connecting wirelessly to a wide variety of health and fitness products.



-Google Maps ™ - With Street View



Find your way to your destination.



-Google Latitude ™



See the existence of your friends - and share your location with them.



-Alignment through Sony Ericsson Sync



Synchronize your phone contacts, calendar, tasks, bookmarks and notes * through the Sony Ericsson website. Sony Ericsson Sync is based on SyncML. * Harmonisation of items may vary depending on the device.



-Alignment through Facebook ™



Match friends up ™ with your phone contacts.



-Alignment via Google Sync



Use your Google account to sync contacts on your phone.



-Alignment - Exchange ActiveSync ®



Stay terselaras without barriers with Microsoft ® Exchange email server.



-Support Micro USB



Connect to PC and other devices.



-WiFi ™ certified



Utilise high-speed Internet at Wi-Fi hotspots at airports ™ and other facilities.



-USB support



Connect your phone to your computer.



-USB mass storage



Connect and move items between your computer and phone.



-TV out



Get the big screen - connect the phone to a television, projector, or other device.



-HDMI Support



Sharing pictures and videos on TV using your TV remote control.



-Modem



Connect your computer to the Web using your phone wherever you are.



-Bluetooth ™ technology



Connect to other Bluetooth ™ devices wirelessly.



-aGPS



Based services utilizing GPS-powered location.



-3.5 mm audio jack



Sharing music via the extra jack. Use any headphones with a standard connector size of 3.5 mm.



-Google Mail ™



With Gmail for mobile, you can send and receive emails wherever you are.

Messaging

-Text messaging (SMS)



Send text greetings anywhere in the world.



-Predictive text input



Text messaging is quick and easy.



-Picture messaging (MMS)



Multimedia messages in color.



-Instant messaging



Online chat on the way



-Email



Check your email inbox wherever you are.



-Conversation



Tell me via SMS chat style.



Communication



-Google Talk ™



Communication style chat with friends and family.



-Noise Shield



Filtering the sound around for your voice heard.



-Twitter ™ - Integration ™ Timescape



Let the world know how you feel and what you think - say via tweet.



-Vibrating Alert



When your phone is in silent mode, you will know if there is an incoming call or message.



-Speakerphone



Hands-free convenience while on the call.



-Sony Ericsson Timescape ™



All your communications with one person in one place.



-Facebook ™ Application



Connect with friends on Facebook ™ via mobile phone



-Design



Keyboard - QWERTY on-screen



Easily insert text



Animated wallpaper



Moving pictures on screen style.



-Touch screen



Intuitive navigation - just touch the screen.



Reality display with the BRAVIA ® Engine Mobile



Crystal-clear colors and sharp images.



Picture wallpaper



Your favorite picture in standby.



Auto rotate



Switching from vertical to horizontal mode by rotating the phone. Whatever your view will rotate to adjust.



Organizer



-Google Calendar ™



Create, add and edit events Set reminders and notifications via cell phone.



-Phone book



The information you need to keep in touch with friends and family.



-Infinite Keys



Only one press to find out all about your friends, or the artist info is needed.



-Flight mode



Disable the radio receivers and transmitters in your phone so you can safely use other functions.



-Document readers



Reading documents in popular formats.

Includes free trial version.



-Calendar



Store names and set reminders.



-Calculator



Fully functional when you need it.



-Android ™ Platform



Powered by the Android ™ for great performance. Personalize with all the applications you need from the Android Market.

Xperia ™ arc is powered by the Android 2.3 (Gingerbread).



-Alarm clock



Set the alarm clock to ring at the time of your choice.



Check my other post : HOT!Electronic Circuit

Electronics Workbench a circuit simulator

Electronics Workbench

Electronics Workbench is the best circuit simulator and testing tool available.

Designing and testing an electronic circuit is a tedious job. Testing is the area where a computer program can be of help; then you will not need to worry that anything will burn up if things go wrong somewhere. Also, the advantage of using ideal components is provided.

Electronics Workbench includes all the tools needed to inspect any electronic or electrical circuit. The circuits can be simulated using ideal components as well as regular ones. It includes a library with a huge list of analog and digital components. If the component you are looking for is not available, you may create it and save it on the user section of the library. It can be done either by editing a component or creating a new one. You will find the chip makers very useful.

Version 5 is a very old one. The component library is somewhat small but it is quite enough for a beginner. The 74xx digital ICs and the general analog ICs, like 741, and also the 555 timer, DAC, ADC, etc., are available. All we need to do is set up the circuit by dragging the components including the measurement devices, function generator, etc., and click on the start button.

Analysis with graphs is available too. It is very useful in constructing bode plots, etc. The program comes with a lot of circuit examples so that you can easily study them. The Circuit Design Community on the Internet is the best source for Electronics WorkBench example files and projects.

The newer versions, like the latest one 10.1, include a lot more components and tools.Download Here