LED Backlight Tester model A : The world first battery TV led tester

[capwizard]

LED Backlight Tester model A : The world's first battery TV LED Backlight tester.


LED Backlight Tester is nothing but a high voltage power supply.

We are going to make battery LED TV Backlight Tester, basically, circuit is one transistor oscillator to a HV DC to DC Inverter.

Inside a bug zapper racket / racquet , with schematic.
https://www.youtube.com/watch?v=yGR2G4qHm6g

Simple Inverter Using D882 Transistor- With Circuit Diagram Explanation
https://www.youtube.com/watch?v=RTDegNtQEh0&t=557s

How To Make Inverter from 1.5v to Ac 220v
https://www.youtube.com/watch?v=_I06m2NHius

If you take out parts from CCFL lamp make your own coil then you can limited output voltage by turns of coil. if you use a bug zapper racket which has about DC 3000v, how can we do it?

to be continued

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

First step we take out voltage tripler circus and then we low down the voltage to 1.5 volt and we put a potentiometer on the base of the transistor so right now we can adjust the output voltage to 320 volt.

Now you have the world's first adjustable TV LED backlight tester.

Next time we gonna put a voltage meter on it....to be continued....

[stj]

Re: LED Backlight Tester model A : The world first battery TV led tester

i need that for something else,
where do you get the bug zapper things?

can you show the other side of the pcb?

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

Come on .....that's put a meter on it. 1.5v AAA battery really can't drive digital meter...so.... what we're going to do is useing 18650 battery. Now we know how much is the voltage LED used.

Next time we're going to do is use lm1117 1.5 volt to limit just use one 18650 battery.

You could put A dual voltage meter with the current display now you have the world's first battery powered LED TV backlight tester...... only over here ...........badcaps.net

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[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

i need that for something else,
where do you get the bug zapper things?

can you show the other side of the pcb?

Ebay....here you are.

Stj:.....i need that for something else,....are you gonna make a ozone generator?

Picture 2.... I'm too lazy to take parts out I just leave one leg up.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

This is a very good holiday small DIY project. Today we want to commemorate him. Martin Luther King. So I'm going to name this TV LED backlight tester the Martin tv led tester model A.

I found one lm1117 1.5v over the junk vizio main board. Soldered inside. that's it....to limit use only one battery.

I put cover and the screws back the finished product is this.....picture 5 and 6.

Fin........

[stj]

Re: LED Backlight Tester model A : The world first battery TV led tester

no ozone generator,
i need a very compact 200vdc psu that runs from 9v or less for my zener diode tester project

[redwire]

Re: LED Backlight Tester model A : The world first battery TV led tester

I use disposable camera strobe power supplies. 1.5V to around 300VDC.
You can add turns to the primary if you want to run off a higher voltage.
I ditch the big electrolytic, and use a smaller 1uF 300V cap.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

no ozone generator,
i need a very compact 200vdc psu that runs from 9v or less for my zener diode tester project

Because I change operating voltage to 1.5 volt for safety reason if you use original voltsge 3 volt. It will have enough current to testes zener diode or Tr breakdown voltage.

See the picture because it's not enough current. I think zener diode test need at least 10 mA.

[vinceroger69]

Re: LED Backlight Tester model A : The world first battery TV led tester

i need that for something else,
where do you get the bug zapper things?

can you show the other side of the pcb?

my local pound shop sells these zapper things dont be tempted too touch it as it bloody hurts lol my nephew got me with one on my arm.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

So... you're a big BUG then

According to my calculation. A bug this big needs at least 10000 volt and enough current to zap.

[vinceroger69]

Re: LED Backlight Tester model A : The world first battery TV led tester

lets just say my nephew learnt a few new swear words that day haha

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

no ozone generator,
i need a very compact 200vdc psu that runs from 9v or less for my zener diode tester project

Two way to solve this problem one is we can change the meter from 16.1 to 18 .0 volt. Picture 1

the other way is use my next project Valentine TV LED backlight CC CV tester model B. Tested current at 10 mA.

I am working on now. Picture 2

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

no ozone generator,
i need a very compact 200vdc psu that runs from 9v or less for my zener diode tester project

Sorry I use cellphone to post. I had Pushed the wrong button.

Two way to solve this problem. one is we can change the meter from 16.1 to 18 .0 volt. Picture 1

the other way is use my next project Valentine TV LED backlight CC CV tester model B.

I am working on now. Picture 2

[stj]

Re: LED Backlight Tester model A : The world first battery TV led tester

i think a zener can be tested at <5ma

the highest voltage zener i come across is 145v,
the meter i will use (DT830) has a 200v scale.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

I found some informations.

This effect is especially noticable in those low voltage zeners of a few volts. For example, a 3.6V zener in my component box have a breakdown voltage of only 2.95V at less than 1mA current, 3.3V at ~3mA and 3.6V at about 5mA or more.

Bear in mind not to exceed the zener power rating and try to keep the zener current within 5 - 15 mA range.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

okay that's put Martin Model A to work.

60 inch Samsung TV has screen backlight blinking problem I thought was the power supply problem so I swapped them is still same thing happened.

I have had a walking panel so I can compare the difference of both tv panels for you guys.
The working Panel is
the blinking panel the voltage is

divided by 3.2 you know how many LEDs are not working

actually the the customer brought this TV From Craigslist about $400. I felt sorry for them but I knew this gonna be a tough job. With so many LEDs are not working. so I pretty firm on my price.

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

okay that's put Martin Model A to work.

60" Samsung TV has screen backlight blinking problem I thought was the power supply problem so I swapped them. Tv still has same problem.

I have a walking panel so I can compare the difference of both tv panels for you guys.

The working Panel is 184v
the blinking panel the voltage is 79.2 that's why caused the overcurrent protection from power Supply.

184-79.2 divided by 3.2 you know 32.75 LEDs are not working

actually the the customer brought this TV From Craigslist about $400. I felt sorry for them but I knew this gonna be a tough job. With so many LEDs are not working. so I pretty firm on my price.

Ps... I glued a magnetic from speaker and Martin Model A works better.

I double post again.

[budm]

Re: LED Backlight Tester model A : The world first battery TV led tester

You will get Vf of around 3 ~ 3.2V if you drive the LED at the rated current, but since you only driving with < 30mA then the Vf will be around 2.8V.
For example look at the Vf VS If graph on page 10.
Low current LED tester is good to certain point, bad LED may light up OK at low current but when you drive it at working that is when bad LED will show bad, I.E. blinking on and off, same if you have bad connectors on the LED strips.
"The working Panel is 184v" at that Voltage, do you see the backlights on?
Is the LCD panel model # CY-DF600CGSV2H (84 LED's)?

[capwizard]

Re: LED Backlight Tester model A : The world first battery TV led tester

You will get Vf of around 3 ~ 3.2V if you drive the LED at the rated current, but since you only driving with < 30mA then the Vf will be around 2.8V.
For example look at the Vf VS If graph on page 10.
Low current LED tester is good to certain point, bad LED may light up OK at low current but when you drive it at working that is when bad LED will show bad, I.E. blinking on and off, same if you have bad connectors on the LED strips.
"The working Panel is 184v" at that Voltage, do you see the backlights on?
Is the LCD panel model # CY-DF600CGSV2H (84 LED's)?

The working Panel is 184v" at that Voltage, do you see the backlights on?

yes, its light was very dim. 84*3.3=277.6v and 184v These two have great differences!

is the LCD panel model # CY-DF600CGSV2H (84 LED's)?

yes 84leds 14 leds x 6 strips leds but panel no. a little bit different, I will let you know tomorrow.

since you only driving with < 30mA then the Vf will be around 2.8V.

I have been thinking about this all day, because the Martin LED tester test one Samsung led result is 3.2v. is it because of the Martin LED tester use half-wave rectification?