GVA HGG3440 - easy fix

[japlytic]

Today, I was given a GVA HGG3440 (most likely a Hisense) to repair, which was said to be about a year old.
Upon removing the back, C553 (1000uF 25V) on the +12V rail was bulging.
The following capacitors were replaced with low-ESR units:

From the power transformer: C551 (+110V), C562 (+25V - upgraded from 330uF to 1000uF), C553 (+12V), C554 (+12.5V)
From the flyback: C477 (+200V), C471 (-13.5V) and C474 (+13.5V).
The 400V unit was replaced with a better quality unit.

After replacing these capacitors, the set was turned on and all of the voltage rails were within specification.

I'm always interested in examining the quality of Chinese electronics, particularly TV sets, set-top boxes and DVD players...

[Wizard]

Re: GVA HGG3440 - easy fix



Worked on several versions of these. Designed sloppily and to the minimum. Terrible solder and worse than fuuuyhi capacitors.

Cheers, Wizard

[Krankshaft]

Re: GVA HGG3440 - easy fix

Dang!! Look at all the pins on that IC!

It must literally do everything.

Most CRTs I see have at least 4-6 ICs inside handling the signals.

[kc8adu]

Re: GVA HGG3440 - easy fix

Dang!! Look at all the pins on that IC!

It must literally do everything.

Most CRTs I see have at least 4-6 ICs inside handling the signals.

thats just the jungle.
the cpu is a qfp on the bottom.
seems meijer stores sold those around here.
a neighbor had one that the crt was shot in 6 months.
the case looked like some sort of spacecraft.
i remember it because the same caps were also bad.
the crt had a logo that reminded me of the band and mounting lugs from a crt.
the only name on it was "picture tube"
at least it was a common small neck 370 that i have plenty of.

[Wizard]

Re: GVA HGG3440 - easy fix

kc8adu,

Yes, it is IT, *everything* in that giant IC, I know because worked on plenty and knew what it is. Anything else is either audio processing IC or inputs switcher IC.

To old farts, that big IC is combined micro, jungle, deflection drive outputs, pre video and pre-audio processing. 8 pin IC is serial eeprom to hold settings (factory and user) only, the firmware is fixed permenantly in the big IC and have I2C bus for controlling audio processor if it has one, tuner, video/audio switch IC if equipped.

Does really good job for what big IC were. What ruins or improve the quality of picture is how is the circuit around this big IC was designed. I have a JVC 27" with this big IC and it is genuine JVC chassis and have excellent picture.

Good ones that uses big IC are:

RCA ITC008
JVC around 2003-2005 mid line series (like AV-27D203 tell tale is 105 watts).

Yeah, 2 chip or more (micro & jungle of good makes are also good as well. But there are also bad ones out there (aka Sharp, generic etc).

Cheers, Wizard

[kc8adu]

Re: GVA HGG3440 - easy fix

I'm always interested in examining the quality of Chinese electronics, particularly TV sets, set-top boxes and DVD players...

you mean lack of quality?

[Krankshaft]

Re: GVA HGG3440 - easy fix

Haha yeah quality and Chinese electronics shouldn't occupy the same sentence .

My Mastech variable digital bench power supply for example an american circuit design ripoff forgot which company originally desgined it. 3 relays to switch windings on the torroid transformer in and out to reduce heat waste in the regulators.

Great circuit but crap caps needed to be replaced before I would even think of trusting it.

[tmwalsh]

Re: GVA HGG3440 - easy fix

Wizard, slightly off topic, but has Sharp taken a dive into junk status? I have a 19e85 that I bought new that still has (to me) a stunning picture. Linytron tube taking a hint from Sony trinitron. It had a problem that 3 repair people could not fix. It was a 1/4w resistor that went open, and I found it after HOURS of measuring, etc.
Other than that, it has been a good set. Did they sell their name to Funai or one of the many Chinese manufacturers?
tom

[Wizard]

Re: GVA HGG3440 - easy fix

Not a problem with Sharp stuff, but once it needs specific parts. Bah! Same iwth Sanyo. RCA is joining the diease where I could not just get parts easily for LCD.

Cheers, Wizard

[percy07]

Re: GVA HGG3440 - easy fix

Hi, I've got what should be a simple problem for you.
I have a noisy speaker in the GVA 32", responds to tapping it so I am assuming it's going to be a dry join on the speaker... But my problem is splitting the TV open.. I've undone all the screws around perimeter at the back.. Removed it from the stand, Now it should just fall apart right? but I am unsure if I should now remove the back.. Or is it the front bezel which has been loosened? Sounds simple, but I don't want to break anything..
It's about 2 years old, so I guess that seems to be average for this model..
Must say it filled in the gap while the rest of the prices tumbled, so at $300 it was probably a good buy (from the Good Guys)

[percy07]

Re: GVA HGG3440 - easy fix

Well, thanks.. Did solve my own problem.. Two screws over the AV female plugs on the back of the set was what was causing me grief.

The noise? Theres a heat sink running down the right side of the TV (when I'm veiwing it.. ) This heat sink is bowed and rattles against the plastic casing. A bit of tape now holds it a little firmer..

Long term, I'll try the AV sound plugs and take them to an old amp I am already using to boost my netbook sound.

Tip for anyone reading, VGA to VGA from my netbook to this TV works fine.. The earplug jack goes to the afforementioned amp, as I am a little hard of hearing, and enjoy watching movies and TV from the likes of Hulu directly to the bigger screen.. I'd have a bigger TV, but thats all that my cabinet can cope with..
The netbook is a HP, and the wifi copes well with streaming from most broadcasters. When not, I will sometimes down load instead of streaming.