delabs Circuits

Friday, July 21, 2017

Continuity Tester

Question - i want a continuity tester circuit or get one.

mail by RB

Here are some pages that might help

Simple Component and Continuity Tester - This simple project may be used for testing components, as well as checking circuit board tracks, wires and connections for continuity (conduction). It tries to pass a small current through the item being tested and the LED will light brightly, dimly or not at all according to the resistance of the item.

POPTRONICS Continuity Tester - This is another invaluable piece of test equipment for digital work. It has been designed by us to cater for a particular application . . . servicing digital projects sent in for repair. 

Continuity Tester, Smart - A tester by Tony Van Roon. This uses a 741 opamp and works off a dual supply and hence rather complex but more accurate. This may need some design changes too.

Silicon Chip Online - A Programmable Continuity Tester - Let's face it, almost every analog and digital multimeter does have built-in capabilities for testing continuity. However, this function is somewhat limited.

It would be a good idea to buy one like this

Continuity Tester CT6101

Heavy-Duty Continuity Tester CT6101- The Continuity Tester is very easy to use and is used to test for breaks in non-energized wires or cords. Continuity has a bright 360 degree visual indicator located near the tip along with a flexible lead for ease of use.

Thursday, July 20, 2017

Simple Battery Characterizer

I was reading about some IC's from Maxim/ Dallas saying " Simple battery characterizer" for plotting a charging/ discharging cycles & graphs are available on computer for study I want to plot an extensive data of these batteries.

From MO

This circuit is a battery characterizer that applies a fixed load to a charged NiCad or NiMH cell and measures milliamp-hour capacity as it discharges.

PIC-based circuit example from Westford MicroSystems - Battery Characterizer that determines milliamp

Simple Characterization Circuit

Simple Characterization Circuit for Rechargeable AA Cells - Maxim.

Abstract: This characterization circuit, plus a PC and some software, accurately measures the full discharge cycle for a rechargeable AA cell. Cell capacity and output resistance can easily be determined from the curve resulting from these measurements. 

delabs

Friday, July 14, 2017

Desoldering Methods

Dear Solderman, i hope you know how to dessolder a wave soldered component from a board. There is problem because the pins are two face soldered. - thanks

mail from JS

Sending a few sites, read them all and then tell me.

Desoldering - Wiki

A component with one or two connections to the PCB can usually be removed by heating one joint, pulling out an end of the component while the solder is molten (bending the other lead to do so), and repeating for the second joint. Solder filling the hole can be removed with a pump or with a pointed object made of a material which solder does not wet, such as stainless steel or wood.

Desoldering Methods

How to Desolder

One of the most frustrating parts of building electronic circuits is getting something wrong. For a board that should take ten minutes to put together, you could spend an hour just trying to fix a component that you got backwards. Sadly, desoldering it’s not as easy as soldering in reverse.

Desoldering requires two main things: a soldering iron and a device to remove solder. Soldering irons are the heat source used to melt solder. Irons of the 15W to 30W range are good for most electronics/printed circuit board work.

Desoldering THM and SMT

Desoldering is a topic that no one seems to get to excited about until the time comes when people discover that a lot of damage is being done during this operation.

delabs

Wednesday, June 14, 2017

Active Camera trigger shutter

well listen i read about an idea but i didn't get it so well and i want to develop it if i understood it with ur help active camera trigger shutter something like that i want to know input output solutions and i was wondering if i can send the picture to a mail and how

mail from MK


Is this what you are looking for....

The HSP DIY system must therefore be a control system. Suitable control systems range from amazingly simple to extraordinarily complex. The tips on the following sections are designed to help you select the type of control system you wish to build and us

Active Camera trigger shutter

Photoflash circuit from pocket camera - This schematic was traced from an electronic flash unit removed from an inexpensive pocket camera, a Keystone model XR308.  Errors in transcription  are possible.

Flash slaves are used when you need to supplement one flash unit with one or several more. This slave trigger simply triggers those other units.

Slave Flash Trigger - A Programmable Optical Slave Flash Trigger  for Digital Cameras with Processor PIC 12F675

delabs


Monday, June 12, 2017

RF Microwave and Wireless Projects

hi im a communications engineering student can u help me to find an idea for my secondary project. i want a hardware project that is related to for example wireless communications , microwave or fiber optics something like that can u help.

mail from MK


Think of the project you want, enter multiple keywords, then see the results. you may need download pdf files by right click save target ,

Cambridge Wireless Resources
"development and application of wireless and mobile technologies to solve business problems."

RF Microwave Projects

Look at these links too....

 Application Notes - RF Cafe -  Useful Learning Application notes on RF and Parts vendor sites.

New Wave Instruments - RF snd Microwave resources

A comprehensive collection of RF & microwave resources for wireless communication engineers. Includes tutorials, theory, design aids, circuit diagrams, products, and more.

First try out above links and google scholar, Then give me more specific ideas, so i can help you better.

delabs


Wednesday, June 07, 2017

Application for 8051 mcu project

Need an unique Application for 8051 mcu project ? - mail by J9


Look at this place

8052.com - The Online 8052 Resource - This web site is dedicated exclusively to the 8052 microcontroller, related products (both hardware and software), and 8052 derivative chips. This includes the traditional 8052, 8051, 8032, and 8031....

The best place is PJRC: 8051 Projects - This 8051 development board provides an easy and low-cost way to develop projects based on the 8051 microcontroller, without the need to purchase any other equipment, such as EPROM programmers or emulators.

8051SBC

8051SBC V1.0 - The old day chips, say 8031, 8751, 8032 or the new chips,89C51, 89C52, 89C51RD2 can be used without any problem. Some may think that your old chips were useless, now you can use it for many projects.

delabs
This is an answer of mine to an old post - 2006

Friday, April 21, 2017

How does RTD Work

How Resistance temperature detector works?

Post by JG

The most popular RTD is PT-100, Platinum 100 Ohms, As all Metals have a Temperature Coefficient of Resistance. The Resistance of RTD increases with rise in temperature.

How does RTD Work

Even Copper wire can be used, but you need to have a very thin and long wire to make usable measurements.

Resistance: Temperature Coefficient - Since the electrical resistance of a conductor such as a copper wire is dependent upon collisional proccesses within the wire, the resistance could be expected to increase with temperature since there will be more collisions

Resistance thermometer - Wikipedia - . The RTD wire is a pure material, typically platinum, nickel, or copper. The material has an accurate resistance/temperature relationship which is used to provide an indication of temperature. As RTD elements are fragile, they are often housed in protective probes.

What are RTDs? - in the case of Platinum known variously as PRTs and PRT100s, are the most popular RTD type, nearly linear over a wide range of temperatures

What is a Resistance Temperature Detector (RTD)? - Most RTD elements consist of a length of fine coiled wire wrapped around a ceramic or glass core.
The material has a predictable change in resistance as the temperature changes; it is this predictable change that is used to determine temperature.

delabs
This is an answer of mine to an old post - 2006