Magnavox tv problem,

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dacflyer
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Post by dacflyer » Fri Apr 20, 2007 3:43 pm

ok, i do not know which is which,,but heres the 3 biggest IC's

TDA8369
TDA9852
620001-1

pick one {:>P

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Janitor Tzap
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Post by Janitor Tzap » Sat Apr 21, 2007 11:13 am

TDA8369: NTSC Video Decoder/Processor.
TDA9852: Stereo SAP Chip.
620001-1: ????? All I can tell you is it is a NAP in house number. :sad:


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Bob Scott
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Post by Bob Scott » Sat Apr 21, 2007 6:28 pm

Janitor Tzap wrote:620001-1: ????? All I can tell you is it is a NAP in house number. :sad:
Network Access Point? Numerical Audio Processor? Not A Part? :idea:

NAP - National Action Plan?
Network Access Protection?
National Association of Parliamentarians?

No, really, what is a NAP part?

Don't get me started on "ATM". :yuck:

Bob

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Janitor Tzap
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Post by Janitor Tzap » Sat Apr 21, 2007 7:40 pm

Bob Scott wrote:
Janitor Tzap wrote:620001-1: ????? All I can tell you is it is a NAP in house number. :sad:
Network Access Point? Numerical Audio Processor? Not A Part? :idea:

NAP - National Action Plan?
Network Access Protection?
National Association of Parliamentarians?

No, really, what is a NAP part?

Don't get me started on "ATM". :yuck:

Bob
North American Philips corp.:)
{But it looks like they're only calling themselves just "Philips" now.}

Oh, Well......:???:


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dacflyer
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Post by dacflyer » Tue Apr 24, 2007 7:53 pm

*bump up *

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Post by dacflyer » Wed Apr 25, 2007 8:22 pm

bumped up again...
where are you Edd?

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dacflyer
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Post by dacflyer » Thu Apr 26, 2007 4:52 pm

boy...cannot belive its so hard to get any help here on this...
am i and Edd the only tv guys here??

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idea

Post by Geoff » Fri Apr 27, 2007 5:59 pm

I am not sure if the Philips chassis I'm thinking of is the one you have, but a common problem is when that 100 uf/ 200V capacitor fails. The B+ goes up, and the horizontal output transistor shorts. This blows a 2 (or 2.5?) amp pico fuse on the board.

Also, on these sets a shorted horizontal output transistor can be caused by bad connections in the area of the drive transformer. I always resolder the pins on those, even if I'm not working on a horizontal/power problem.

If you test the horizontal output transistor in-circuit, you will read a short base to emitter. This is normal; you're seeing the secondary winding of the horizontal drive transformer. If you see a short collector to emitter, its bad. (or something on the B+ line is)

You sometimes see these sets show a horizontal hold problem before the horizontal output blows. This is the set trying to cope with too much high voltage. The size may change as average brightness changes.

I hope this helps

Geoff

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dacflyer
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Post by dacflyer » Fri Apr 27, 2007 10:27 pm

geoff >> sorry, but if you read my post you would have seen that i had said i already had checked all that stuff,,,,,thanks anyway...

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Post by Edd » Sat Apr 28, 2007 11:12 am

.

Without having to delve through all of the potential schemas in the LRC resources, would you pls positively confirm that, in reality, the PS IC the set uses is a STR30130 series and not being another number of unit.
Referring to, and using a new reference posting at the Sams site while retrieving the latest index, shows no referencing of a STR30130 ever having been used in their sets chassis that are encompassed on that lists concurrent timeframe . Nor do your two other reference IC's, with the exception of the long numbered one, taunted as now being in a NLA category.

Tech reference:
http://www.samswebsite.com/Sams_IC2PF_111705.pdf

Also, I wonder what the possibilities are of that unit have been a ****ard offsping, made by another manufacturer....over the waters..and then their having placed their MAG name upon it.
In the interim another thought to check, see if there is a 12, 9, or 5 VDC three terminal regulator involved in the design and then check out the electrolytics at its input and outputs for their ESR, as well as any large value Raw DC electrolytic reservoir filter associated with their
supply circuit. Since I believe that you did not mention any CRASH and BURN of any / other components on the chassis proper.
( Nor ..as mentioned....any burnt open micro fuses that are as small as, and sized like yellow or black 1/2 watt carbon comp resistors.)

Standing by for feedback...such that I can break out into further spurious oscillation.

73's de Edd
[email protected] ...........(Interstellar~~~~Warp~~~~Speed)
[email protected].........(Firewalled*Spam*Cookies*Crumbs)
:grin: :razz: :grin:

Since sponges grow in the ocean. I wonder how much deeper the ocean would be if that didn't happen.

.

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Post by dacflyer » Sat Apr 28, 2007 9:24 pm

Edd >> this is indeed a magnavox boob tube set..
and as you will see in the fotos it does use a STR30130 regulator..
i do have my B+ and 5 volts..but i cannot find any other regulators or voltages..

even the pix tube is phillips.

see fotos as proof...
Image

Image

Image



as little richard says in the geico commercial...SOMEBODY HELP MEH !

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Janitor Tzap
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Post by Janitor Tzap » Sun Apr 29, 2007 10:03 am

dacflyer,

Don't drive yourself crazy working on this dog of a set.

If you really like it that much, just replace the main chassis module.

Here's PTS Electronics.
http://www.ptscorp.com/television.html
They been rebuilding Chassis's and Tuner's for some 25 years.

I know this isn't what you wanted to hear.
But sometimes it is easier to just swap out the old board for a rebuilt one.
Than spending hours doing component level replacement on a board.


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Bob Scott
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Post by Bob Scott » Sun Apr 29, 2007 5:24 pm

dacflyer wrote:boy...cannot belive its so hard to get any help here on this...
am i and Edd the only tv guys here??
I don't think you're the only tv guys but I don't think that there many TV techs left. My experience is almost exclusively with Sony broadcast monitors from over 10 years ago. The last local TV repair shop around here closed 3 years ago.

I'm actually surprised that there is anyone still doing consumer TV repair and making a profit. New analog CRT sets are so cheap.

Bob :shock:

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dacflyer
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Post by dacflyer » Sun Apr 29, 2007 7:19 pm

replacing the chassis cost as much as 2 new sets..lol
plus i like the challange.....usually a set doesn't whip me,,but this one is being a real pain !..
i almost think its the jungle chip , i googled the other chips,,but they list as NLA..except for the audio processor

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dacflyer
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Post by dacflyer » Fri May 11, 2007 9:11 am

well i am still working on this gagbox tv..
but i have narrowed it down to this,, i have my 5 and 8 volts source,,but as soon as i push power..the voltages goto almost zero...
i am sure its a short,, Edd sent me a schematic,,but the circuit is kinda complicated for the 5 and 8 volt sources..i have checked all i can think of,,
but no luck yet..

if i shared the schematic with anyone,,,think you can help me ?
getting desperate here...

i already checked tons of stuff in the area.but nothing checks bad yet..

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