LG 32LE5500 - dead tuner

[rob77]

Hi Guys,

my TV broke down today everything works fine except the tuner - it's not able to pickup any multiplex (i'm receiving approx 10 of them). it's definitely something with the tuner because with a DVBT set-top-box connected to the same antenna cable i have all the TV stations i had before.

so what i did:

1.  downloaded a service manual
2. checked the tuner's schematic - it has 4 power rails 5V, 3.3V, 2.5V, 1.2V  , the 5V and 3V3 are just the generic rails (those for the rest of the circuits)+ some additional LC filter , 2V5 is from an LDO and 1V2 is from a buck converter. - checked all of them with DMM & scope - and those are nice , clean and spot on.
 
so i think it's the tuner itself - it's dead. the TV is able to switch to antenna input - i can even start scanning the channels - but 0 found.
the tuner's part number is :  TDFR-G135D

now my question is ... where can i buy a new tuner ? google is not very friendly when searching for the tuner part number.

[fluxcapacitor]

For LG parts north.pl might have what you are looking for .It may be cheaper though to buy a used mainboard on ebay .

[Rasz]

yeah
http://north.pl/karta/tuner---glowica-ebl60740403,733-GU-0505.html

almost $60  lol, and you still wont sure its tuner, and not the decoder IC on the motherboard.

have you looked at the tuner output on a scope?

[Psi]

Have you checked if the composite/hdmi inputs still work and display video?

[rob77]

Thank you very much for the suggestions/comments.

@Psi - HDMI works ok - tested with laptop &  DVBT set-top-box - both video and audio are ok , got no composite video source to test with.

@Rasz - actually that's a good idea,  thanks for that - going to tear it down again today evening and check the outputs with a scope.   and thanks for the link - probably i'll place the order after probing the first output pin

thank you Guys    , i'll keep you updated

[Rasz]

are those tuners also decoders? do you have a pinout?

btw this dude
http://allegro.pl/tuner-glowica-tv-lg-tdfr-g135d-ebl60740403-i4261407153.html
his contact: bok@icmarkt.com

tried to sell new one 2 months ago and failed, price is almost 1/2, he is also in Poland, might be worth a try if you really want to spend that much.

[rob77]

that tuner is a mixed analog/DVBT - it has analog out + 8bit data bus for DVBT with control lines + a bunch of signaling outputs + seems to be an I2C (or similar).

i'm at work now, so i'll have time to dig into the schematic and test with scope in the evening.. i'll update you.

but anyways... probably it would be worth of looking after a pure digital tuner with the same pinout.. the analog output of the tuner is useless nowadays not a single analog terrestrial TV channel over here.
i'll definitely check the tuner with scope in the evening, and if it's definitely dead then i'll tear down the tuner itself to see the digital chipset inside and probably it would be easier to find a pure digital one for a better price (or even buy a cheap DVBT set-top-box with the same tuner chipset  and take the whole tuner from there).

[fluxcapacitor]

yeah
http://north.pl/karta/tuner---glowica-ebl60740403,733-GU-0505.html

almost $60  lol, and you still wont sure its tuner, and not the decoder IC on the motherboard.

have you looked at the tuner output on a scope?

i didn`t check whether one was in stock or how much it might cost, it was only a suggestion.

The no channels problem could be due to buggy firmware -

http://openlgtv.org.ru/forum/viewtopic.php?f=9&t=718

[rob77]

thanks for the link to that forum  it's interesting reading and i picked some useful info from there
but i think the firmware is not my case - i have that TV for something like 4 years and the firmware was not upgraded recently (at least i'm not aware of any upgrade).. and actually the tuner died yesterday.

unfortunately i had no time for further checks today  but i hope tomorrow is the day the TV is running happily with a DVBT tuner connected via HDMI (only problem is that i have to use 2 remote controllers now )

[sunnyhighway]

not a single analog terrestrial TV channel over here.

You could take the tv to a friend or neighbor who has cable tv.
Despite the fact DVB-C is gaining popularity, most cable-tv providers still provide some analog channels.

If tuning the analog channels failed there too, the tuner is dead for sure.

[Rasz]

not a single analog terrestrial TV channel over here.

You could take the tv to a friend or neighbor who has cable tv.
Despite the fact DVB-C is gaining popularity, most cable-tv providers still provide some analog channels.

If tuning the analog channels failed there too, the tuner is dead for sure.

or just connect a vcr if you have one

[rob77]

not a single analog terrestrial TV channel over here.

You could take the tv to a friend or neighbor who has cable tv.
Despite the fact DVB-C is gaining popularity, most cable-tv providers still provide some analog channels.

If tuning the analog channels failed there too, the tuner is dead for sure.

or just connect a vcr if you have one

i don't have one. i'm using DLNA + HP micro server with Linux. temporarilly solved the recpetion with the dvbt set-top-box, but hopefully today'll dig deeper and probably track down the issue with the tuner.