Old school Fortune Magic Green 14" S/N 96097669 CRT

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

this is likely too late to post the picture but New year and Christmas is a busy time

so here it is

[Th3_uN1Qu3]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Lower Rds = better. Try to match Qg (gate charge) also.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

A full schematic of the circuit that switches power to the TDA9102 might help. That B649 transistor is supposed to switch power to the TDA9102. If you find exactly what is connected to the base and collector of the other transistor, you can start testing components to see why that circuit isn't working.

What's going on with those film caps (marked 824)? Do you still have the two smaller caps in parallel to replace the bad one?

I am think same this B649A supposed to switch the power for TDA9102 but it has checks B649A good, yes, i have checks all the transistor connected to B649A. Iam also checks all resistor and diode off circuit but nothing were defect. This monitor looks like doesn't have any schematic anymore. I couldn't find it on googling.

the caps 824J is still there and no problem. I try to touch it and getting not too hot. I don't replace it with two 474J paralled. My question is Mosfet looks like very hot. It looks like I have to find another replacemnet. Lower Rds would be a pain on mosfet replacement?

[lti]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

A full schematic of the circuit that switches power to the TDA9102 might help. That B649 transistor is supposed to switch power to the TDA9102. If you find exactly what is connected to the base and collector of the other transistor, you can start testing components to see why that circuit isn't working.

What's going on with those film caps (marked 824)? Do you still have the two smaller caps in parallel to replace the bad one?

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Some update here, pardon me if digging out the old post, but i want to thank you for all of you contribute in this thread and help me out to find the problem.

I am just too upset when get a bad picutre before, so I am just laying the monitor down on bench. A couple days ago I am success fixing my friend TV and the problem just a badcaps and failed HOT (he give me a reward ).

Today I have many spare time and decided to try fix it again, I am trying the suggestion, replacing IC LM358 and caps 100uF 35v, the really one that messed me up is a cold solder joint on TDA9102 pins (forget to makes note) that I am missing !! I haven't change 824J caps (found no replacement).

Yes, maybe the jumper is not supposed be there, but I have try the monitor on and watch a video about 3hours and just fine
I have try all my best but they are no defective components as I checks, so I am still use this jumper method. Now the monitor run likes a charm regarding the jumper (maybe it should be there before??). The colors is very perfect and the lcd monitor that I used looks like a crap comparing with this monitor color. I would post some picture soon because the color is amazing beautiful.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

I presume it should work on VGA / SVGA input.

Have you tried the front panel controls?
I doubt 824 cap would cause. But I wouldn't allow set to run for long periods until one is installed.

yes, i have try front panel controls, brightness, widthness, pincushion, etc. I still get this screen. no change.
this monitor input cable is VGA input like usual LCD monitor input. so how we call for this symptom for tv technician?

I want try to read some site that has mention symptom like this I face but I don't know how they are TV technician call this symptom.

I think like you before that this caps no problem, but after changes it with two parallel 474J, the screen looks like this (divided).
for note : before changes caps the screen just like wave without any clear picture..

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

I presume it should work on VGA / SVGA input.

Have you tried the front panel controls?
I doubt 824 cap would cause. But I wouldn't allow set to run for long periods until one is installed.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

As far as leaving it jumpered, YOUR set, YOUR safety, YOUR call.

As you said My safety, I'm afraid for leaving it jumpered . I don't buy LM358 IC and 824J 400V polycaps yet. I'll try it after have a time.

What symptom like this on my screen to call for TV technician?

I wants to learn and search google where section could be the causes to be checked for this "divided screen" symptom likes I call. that's so many symptom as i see before like no raster, horizontal line, blurry, ghosting, etc and because of language barrier I don't understand clearly..

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

btw where is B+ pin on TDA9102?
&
for the IC
KA3842BN
NE555 Timer
Weltrend WT8043 N201
TDA 9102C/T
TDA 8172
LM358 Op Amp
CA 3080

I have already download all datasheet.

Does set fire up if 12V is connected momentarily to pin #20 of TDA9102?

As far as leaving it jumpered, YOUR set, YOUR safety, YOUR call.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

I am try to make the setting normal, any site to guide me how to set properly?
Yeah, i'll try to buy and changes it. but I am just wondering if this not solve my problem, could I just jumper this permanently?

I have try to checks components all surrounding this IC and NE555, but components near TDA9102 checked good yet. so remain this circuit i have to checks..btw where is B+ pin on TDA9102?

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Make sure computer is set to a resolution that the computer monitor is capable of displaying.

Dual op amp IC is cheap. Worth a try.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

If there was NOT any jumper there to begin with ?? NOT the 'correct' way to repair set.

Can you post picture of "looks divided 4 parts horizontally?"

Here it is..

I have checked all surrounding components, except ceramic, polymer caps. I don't have capacitance meter. maybe the LM358 IC itself, but i try to measure between GND and VCC, no dead shorted..how do you think?

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

If there was NOT any jumper there to begin with ?? NOT the 'correct' way to repair set. 12 volts probably needs to be 'switched' to that trace. Quite likely will be something in the circuit you started drawing earlier.

Can you post picture of "looks divided 4 parts horizontally?"

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

I was saying that the TDA9102 IC had NO B-Plus. By bypassing (jumping this connector) you are just proving that it is CAPABLE of working IF you correct the initial problem. That connector could be for factory 'aging' the set.

With jumper still connected, does POWER button turn set ON & OFF?

Some monitors require a signal to give other than white raster.

yes, with jumper still connected, power button turn set on & off looks normal.

I have test it connected to my CPU. it has a picture.. but it looks divided 4 parts horizontally. so I can't make this jumper permanently? I have to track a B+ trace to this IC TDA 9102 find for culprit?

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

I was saying that the TDA9102 IC had NO B-Plus. By bypassing (jumping this connector) you are just proving that it is CAPABLE of working IF you correct the initial problem. That connector could be for factory 'aging' the set.

With jumper still connected, does POWER button turn set ON & OFF?

Some monitors require a signal to give other than white raster.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Just for a second.
IF B plus is all that is missing to run that IC, then the High Voltage should come up. Then you'll have to figure out how/why its not making it there.
On the other hand, the worst that could happen is smoke, fire, flames.

B+ is not missing, it was measured as 100VDC. Hey bro, you and I MAKE it !! Thank you so much I am just realize there is a little connector that I think ever disconnected by someone, and I makes a jumper between this two connector that looks like a bare terminal block..and BIZZARE !! her live !!

But I got no picture, just a raster likes white screen..I try changes all screen setting but nothing, try changes 824J 400V poly caps that looks black burned and makes me guess (still acceptable I think before) with two parallel 474J I am get picture but it was divided into 4 horizontal picture.. So I think the next is find this critical value caps and I will get this girl back from death...
I think there is no problem anymore, but how do you think? any ideas?

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Just for a second.
IF B plus is all that is missing to run that IC, then the High Voltage should come up. Then you'll have to figure out how/why its not making it there.
On the other hand, the worst that could happen is smoke, fire, flames.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

MOMENTARILY! short the 'IN' & 'OUT' stakes in your drawing on picture.

from momentarily, I think that you means just a couple of second to short it? or makes a wire jumper permanently on this circuit?

[jts1957]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

did you mean I makes a jumper 12V for this IC?

YES ... see next sentence...

MOMENTARILY! short the 'IN' & 'OUT' stakes in your drawing on picture.

[senz_90]

Re: Old school Fortune Magic Green 14" S/N 96097669 CRT

Vcc pin LM358 has 12V, but TDA9102 no voltage.
I have checked the trace and parallel connected to PSU connector to power button led.

it has 5V marked on the board before TDA9102 from power supply trace that connected to power button led. but i just get around 1.5 V DC. This is normal for Vf led, but this TDA9102 IC need 12-18 volts to active right? I have checked this parallel trace too that has 1 ceramic caps, 1 electrolytic, and zener diode but checks good..this gonna crack my brain. lol

did you mean I makes a jumper 12V for this IC?