which components are used in tv circuits?

[legend killer]

Hello everyone
I saw tv circuit board and i could identify few elwctronic components like capacitor, resistors, i guess diodes and few mysterious components which i couldnt identify. What are other electronic components used in tv circuits. Just curious to know
Regards
Lk

 

[alec_t]

.... integrated circuits, inductors, varistors, bipolar transistors, field effect transistors, LEDs, LCD displays, connectors, .....

 

[legend killer]

Thanks alec_t for the reply.
Can you please tell me what is the name of the three terminal device in the pic. I found that in Tv circuit board.

 

[tvtech]

Hello legend

That is a PTC (Positive Temperature Coefficient) resistor. Found in CRT TV's and used for controlling the tube degaussing.

Regards,
tvtech

 

[legend killer]

Hello tvtech,
Thank you very much for the reply.
Is it a variable resistor since it has got three terminals?
regards
Lk

 

[tvtech]

Is it a variable resistor since it has got three terminals?

Lk

Hello legend

I suppose if one STRICTLY tries to define it, it is in a way. However, not like a normal variable resistor (pot), that has 3 legs and an adjustment slider.

A PTC is a sealed device. No adjustment. They use a special type of resistor inside (two in a three pin and one on the 2 pin variety).
These magical things when cold have a very low resistance. When a TV is switched on from cold....and they sense the power...get cross and hot very quickly and go to a high resistance and stop the degauss coil burning out.

And then stay hot for ever and a day as long as the TV is working. That is the simplest I can explain them. However, for much more detailed and complicated information check here: https://www.resistorguide.com/ptc-thermistor/

And yes, a Thermistor is part of the Resistor family. Just keeping things simple and basic here. As per the question .

Regards,
tvtech

 

[Nigel Goodwin]

That is a PTC (Positive Temperature Coefficient) resistor. Found in CRT TV's and used for controlling the tube degaussing.

Actually not exactly correct

It's a 'Posistor' - used (as you said) for deguassing, but it's two thermistors, a PTC one and a NTC - the PTC reduces the power to the coils, and the NTC one 'shorts' out the coils.

Only the two pin ones are PTC only.

 

[tvtech]

I just knew this was going to happen....but I fell for it anyway. So Nigel and I had a similar Posistor vs PTC thing about 2600 Posts before this one when I just joined here. I kept thinking with my reply to legend killer I must mention "Posistor" somewhere..Nah I decided. It's just going to complicate things.

And so it goes on

No sweat. Love this place.

Regards,
tvtech

 

[dr pepper]

I have a drawer full, probably never use them.

 

[Nigel Goodwin]

I have a drawer full, probably never use them.

I chucked them all away

We don't even look at CRT sets any more.

 

[tvtech]

I chucked them all away

We don't even look at CRT sets any more.

Hello Nigel

Unfortunately, someone here has to. And there are very few of us left. I mean about ziltch.

So I often feel like telling the tossers to take their stuff and throw them in the sea..chase them away so I cull all the rubbish out there....but they keep coming.

No end to it. Ever. Just when I think I have seen the very latest and very last CRT...the next batch arrives.

And then they refuse to listen. Please help me they say??

As a Moderator Nigel you would have seen and read my frustrations here. I keep asking these Idiots "WHERE ARE YOUR OWN TECHNICIANS?

Silence from them. Make like they don't understand. My repair again. They act dumb.

I feel like shouting and swearing again because Tomorrow is Monday...and the TV's are going to pile in again. And I am one. Zero backup.

My Champ Bench Tech is in Chemo. I don't think he will be back ever. All these useless customers are relying on me to help them...a White Guy???

I am so over this ****. Please delete as you see fit Mods.

Rant over.

tvtech

 

[JimB]

take their stuff and throw them in the sea

Please don't do that, dumping stuff in the oggin is illegal, contrary to various international conventions observed by most civilised countries.

I keep asking these Idiots "WHERE ARE YOUR OWN TECHNICIANS?

These IDIOTS are your CUSTOMERS.
It is very often the case that customers are idiots, this happens everywhere, but at the end of the day it is the customer who pays your wages.
No customers = no income.
"THEY" do not have technicians, that is why you have a job fixing the obsolete CRT based TVs.

I understand where you are coming from with this line of though, but you are wishing yourself out of a job.
So, what is your "plan B" ?
What would you like to do if there were no more CRT based TVs to fix?

JimB

(Quite a bit of thread drift going on here, and I seem to be a major contributor.)

 

[fezder]

Legend, if you salvage crt's you'll find some beefy components inside (fets and stuff,) but please, be careful, there can be quite high voltage lurking there (warning labels are there for a reason) these guys know much more than me, trust their word! and umm before i forget, welcome buddy!

*mostly applies to LCD/PLASMA tv's also...

 

[tvtech]

Please don't do that, dumping stuff in the oggin is illegal, contrary to various international conventions observed by most civilised countries.


These IDIOTS are your CUSTOMERS.
It is very often the case that customers are idiots, this happens everywhere, but at the end of the day it is the customer who pays your wages.
No customers = no income.
"THEY" do not have technicians, that is why you have a job fixing the obsolete CRT based TVs.

I understand where you are coming from with this line of though, but you are wishing yourself out of a job.
So, what is your "plan B" ?
What would you like to do if there were no more CRT based TVs to fix?

JimB

(Quite a bit of thread drift going on here, and I seem to be a major contributor.)

Hi Jim

A complicated scenario...lets say I had and was working with a competent crew that knows how to fix sets. Maybe three that could replace the ONE good bench tech I had working along side me....still would not be OK. This is Africa Jim.

The good Tech working beside me will waste less, fix more and steal buggerall....

The other crew will create havoc by trying anything and everything to get a set fixed. Swapping parts...doing this..doing that...

Ask them what they did to get the set working...they cannot tell you....so you cannot cost it properly. So you cut your losses and charge a Maximum fee..say R1000....

Back at the ranch....maybe R3000 was spent on the repair. Bad for a business.

Back to your original question: Idiots are my Customers. I promise you as as much as I threaten to throw in the Sea...so they will send more.

Have I a Plan B = NO. I am just tired of this load on my plate...I have no life anyway.

As long as a whitey is here slaving away....the fodder will bring their stuff here to be fixed.

Time for a song. Stuff this.

 

[dr pepper]

Repairing tv's itself is a dissapearing business, you'll be aware of that nige.
Seems that folks have enough readies now to throw out their telly when its just out of fashion rather than it being broke.

 

[debe]

I live in a small rural town that once supported 3 TV/VCR techs. Today there is none, & I don't even bother anymore. The electronic equipment is so cheap to buy.

 

[4pyros]

Hi Jim

A complicated scenario...lets say I had and was working with a competent crew that knows how to fix sets. Maybe three that could replace the ONE good bench tech I had working along side me....still would not be OK. This is Africa Jim.

The good Tech working beside me will waste less, fix more and steal buggerall....

The other crew will create havoc by trying anything and everything to get a set fixed. Swapping parts...doing this..doing that...

Ask them what they did to get the set working...they cannot tell you....so you cannot cost it properly. So you cut your losses and charge a Maximum fee..say R1000....

Back at the ranch....maybe R3000 was spent on the repair. Bad for a business.

Back to your original question: Idiots are my Customers. I promise you as as much as I threaten to throw in the Sea...so they will send more.

Have I a Plan B = NO. I am just tired of this load on my plate...I have no life anyway.

As long as a whitey is here slaving away....the fodder will bring their stuff here to be fixed.

Time for a song. Stuff this.

What would they all do if you stopped fixing the old TVs?

 

[Nigel Goodwin]

What would they all do if you stopped fixing the old TVs?

He wouldn't have a job any more

I fail to see what he's complaining about - fix the old CRT sets (which at least ARE fixable), and take their money. It's a LOT easier than trying to fix LCD or Plasma.

 

[tvtech]

He wouldn't have a job any more

I fail to see what he's complaining about - fix the old CRT sets (which at least ARE fixable), and take their money. It's a LOT easier than trying to fix LCD or Plasma.

No comment. Except for be here and live it. Then we will be on the same page.

Regards,
tvtech

 

[gary350]

There are lots of good parts, resistors, capacitors, heat sink, chokes, power transistors, connectors, wire, transformers.

Most of the ICs are special items just for TVs. There are gang capacitors and strip resistors made special for TVs too. Transistors often have only a manufacturer identification number part number like #34 and NO transistor number. Diodes are the same thing no clue what most of them are. The are many TV parts that are not very useful for home projects. Capacitors with no values need to be tested to find out what they are but it is not easy to determine the voltage rating. Factories order parts in very large quantities usually special order with special number just for them. Numbers are useally small 2 or 3 digit for quick identification. Part 1-5 on a capacitor might mean .1uf 50v or it many not mean anything at all to us. Factories may have a list of parts 1-1 to 100-100 you look up a number like 32-21 to lean that means .001uf 35v. You need to test the parts to learn what they are sometimes that is more trouble than it is worth of you have a 1000 used caps you have to test them 1 by 1 until you find the one your looking for then you still have no clue what the voltage rating is. Parts are usually ok to use in low volatage circuits. Be selective what you save from old TVs most of it is trash.