LG 32LE5500 - dead tuner - Page 1
Forum section: electronics / repair

author: rob77
author_rank: Super Contributor
timestamp: July 13, 2014, 08:18:58 pm
content: Hi Guys,my TV broke down todayeverything 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 manual2. 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-G135Dnow my question is ... where can i buy a new tuner ? google is not very friendly when searching for the tuner part number.

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: July 13, 2014, 11:55:16 pm
content: For LG parts north.pl might have what you are looking for .It may be cheaper though to buy a used mainboard on ebay .

author: Rasz
author_rank: Super Contributor
timestamp: July 14, 2014, 04:14:06 am
content: yeahhttp://north.pl/karta/tuner---glowica-ebl60740403,733-GU-0505.htmlalmost $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?

author: Psi
author_rank: Super Contributor
timestamp: July 14, 2014, 06:36:28 am
content: Have you checked if the composite/hdmi inputs still work and display video?

author: rob77
author_rank: Super Contributor
timestamp: July 14, 2014, 08:16:21 am
content: 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 pinthank you Guys, i'll keep you updated

author: Rasz
author_rank: Super Contributor
timestamp: July 14, 2014, 09:28:45 am
content: are those tuners also decoders? do you have a pinout?btw this dudehttp://allegro.pl/tuner-glowica-tv-lg-tdfr-g135d-ebl60740403-i4261407153.htmlhis contact: bok@icmarkt.comtried 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.

author: rob77
author_rank: Super Contributor
timestamp: July 14, 2014, 09:53:20 am
content: 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 nowadaysnot 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).

author: fluxcapacitor
author_rank: Frequent Contributor
timestamp: July 14, 2014, 07:36:13 pm
content: Quote from: Rasz on July 14, 2014, 04:14:06 ami 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

author: rob77
author_rank: Super Contributor
timestamp: July 14, 2014, 08:32:41 pm
content: thanks for the link to that forumit's interesting reading and i picked some useful info from therebut 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 todaybut i hope tomorrow is the daythe TV is running happily with a DVBT tuner connected via HDMI (only problem is that i have to use 2 remote controllers now)

author: sunnyhighway
author_rank: Frequent Contributor
timestamp: July 15, 2014, 07:28:06 am
content: Quote from: rob77 on July 14, 2014, 09:53:20 amYou 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.

author: Rasz
author_rank: Super Contributor
timestamp: July 15, 2014, 08:25:11 am
content: Quote from: sunnyhighway on July 15, 2014, 07:28:06 amor just connect a vcr if you have one

author: rob77
author_rank: Super Contributor
timestamp: July 15, 2014, 11:52:57 am
content: Quote from: Rasz on July 15, 2014, 08:25:11 ami 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.