Finlux 26FLD745T Tuner (?) trouble

[26fld745t]

Hello.

I have this TV assembled in holland, problem is this:
when i try to tune in channels, or monitor the TV signal strength at UHF channel 44,
it (edit: the TV´s signal strength meter, horizontal bar) bounces from left to right, left to right repeatedly and random, from very good to no signal at all (image and audio freezes). At some moment it stays a couple of seconds in "good" or "very good" but then it suddenly collapses to no signal at all.

At channel 32, 562MHz it bounces a little but it does not affect reception.

At channel 58 the signal strength stays very good, also no problem.

So, the tv is not useable when trying to receive terrestrial free-to-air mux-b of finland, channel 44 at 658 MHz.

This far i have replaced the tuner part it self, but it did not solve the problem. Main a/v board part number is 17MB22-2

There is also a conax reader circuit board which has 4 stickers that read:

TDM PEV
138TPV36

26238816 TDM
20333598 1300
FINLX-PAN-325

IDTV KART 20333598
(BARCODE)
20333598

IDTV 225912
xx xxxx xx ROHS
(the rest of this sticker is messed up)

The problem is not in the antenna and not in the antenna cable.

I replaced one capacitor (Chang 3.3uF 50V) on the main board because tapping the cap with screwdriver made the picture freeze in every channel. Allthough this soldering did not resolve anything.

Dear all, where should i look for fault now? I have googled some time but this Finlux model has not left many traces in internet.

Best reguards,
I.A.

[selldoor]

Re: Finlux 26FLD745T Tuner (?) trouble

Did it ever work in Finland - was it bought in Finland or in Holland

Does it work with other inputs - dvd/ scart/ PC
Is there any sound?

[tom66]

Re: Finlux 26FLD745T Tuner (?) trouble

Check if 33V from PSU is stable, this is used to keep tuner tuned.

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Thanks for the quick reply! Yes, it did work here. It is bought from finland abt. six maybe seven years ago, and is used in finland.

Sound is ok, HDMI input is ok, SCART input is ok. All other TV channels are ok (tolerable) but the mentioned ch. 44 is a disaster.

Bottom channels 562 mhz mux A,
there is little bouncing in reception but it can be used.

Middle channels 658 mhz mux B , a lot of bouncing, signal totally lost every few seconds

Top channels 770 mhz mux C, 100% signal, no bouncing.

Edit: i´ll check the PSU, thanks again

br

I.A.

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

At PL807, pin number 4 from left,
of PSU there is 34.1V which is steady. Edit: that is all connectors disconnected. I´ll measure them next when everything is connected and live, tv turned on.

Edit: 33.9V steady, tv turned on, channel 44, all connectors connected. Signal keeps disappearing and coming randomly.

[selldoor]

Re: Finlux 26FLD745T Tuner (?) trouble

Can you get that channel on another tv using the same aerial
According to wiki which may be out of date channel 44 is the discovery channel
and is not free to air?

http://en.wikipedia.org/wiki/Televis...al_terrestrial

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Works fine with my other tv:s and my measuring instruments. Here are frequencies and channels in finland´s dvb-t free to air network network:



Here is the content of multiplexes in finland:

http://www.digita.fi/kuluttajat/tv

best reguards

I.A.

[tom66]

Re: Finlux 26FLD745T Tuner (?) trouble

TV is configured for Finnish region? MENU 4 7 2 5 (in sequence, while powered on) for service menu then check if right DVB table is loaded.

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Should be configured for this region. It has never been in any other region than here, from shop to the table. I tried to enter the menu several times, but failed.

Should the MENU button be kept pressed while entering the numbers, or should it be pressed all the time while entering 4 7 2 5 ?
a.k.a. "Never entered any TV´s service menu before... "

[tom66]

Re: Finlux 26FLD745T Tuner (?) trouble

These Vestel can corrupt settings randomly...

Sometimes, you need to go to an analog TV channel (with snow), press 4,7,2,5 and then press MENU.
Other times (most new Vestel), you have to press MENU, wait for user menu to appear, then press 4,7,2,5.

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Tom66,

thanks for the advice. Analog channels -> Snow -> MENU -> 4725 made it this time. But, everything appeared to be ok. I performed reset, just for kicks but nothing changed, nor bad or good. Off topic, is there a pre-amp of somekind in the tuner?

What should i try next with this?

[tom66]

Re: Finlux 26FLD745T Tuner (?) trouble

What options do you have in the service menu? Reset just goes back to defaults, if it thinks it is a Swedish TV it will reset back to Sweden. Note this is sometimes different from the user option. I had a Samsung 32" LED with poor Freeview (DVB-T) reception, and it was set to Netherlands region. And when I went into the user menu, it would only allow other Nordic regions to be selected. Changed it to the other Europe setting (IIRC, it had EUROPE-NORDIC and EUROPE-OTHER) and it worked first time. Reset didn't fix it, gave same options as before.

[selldoor]

Re: Finlux 26FLD745T Tuner (?) trouble

You said you replaced the tuner - was the set exactly the same with the old one.
was the replacement a new one and exactly the same part number.
Check the centre pin is soldered correctly

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

You said you replaced the tuner - was the set exactly the same with the old one.
was the replacement a new one and exactly the same part number.
Check the centre pin is soldered correctly

Exactly the same part number, new and soldered properly. A Thomson tuner that is. No datasheet/application note available at least via Google.

Scariest/funniest thing was that nothing changed by changing the tuner part.

I´ll go make some coffee and take a deeper look in the service menu..

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Factory Mode

Video Setup
Audio Setup
DRX
Options 1
Options 2
Options 3
Service Scan/Tuning Setup
External Source Settings
Picture Mode
Reset TV-set

26CMO_L01_DY
17MB22_FINLUX_IDTV_0.0.191
IDTV_v1.4.5

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Tuner Options- menu

Control Byte < +187 >
Low-Mid - LB < +48 >
Low-Mid - HB < +9 >
Mid-High - LB < +240 >
Mid-High - HB < +26 >
BSW1 < +1 >
BSW2 < +6 >
BSW3 < +12 >

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

Service Scan/Tuning Setup

Search for L/L´ <yes>
Pref. Search Standard <L/L´> (other possible settings for this are <m> and <bg,dk,i> )
Station Ident <YES>
ATS Delay Time (ms) <50>
Color Kill Thr. <+70>
Agc Thr. <+200>
Ovm Thr <+160>

Tuner Options (as in my previous post)

Edit: found this

http://wwwproject.org/schematics/fil...s%2017MB22.doc

by googling the menu items. Almost everything in that .doc is identical with this Finlux i have.

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

The main a/v boards "CPU" cooling has been quite poor. A copper strip glued to the chip.. Downside of the board, under the chip, has turned color to brownish.

Also the other circuit board, which holds the pay tv card reader slot... The big chip on that one has been quite hot, the text has faded. Those two circuit boards are obviously quite tightly "married" to each other, there´s that ribbon cable and a cable with 3 leads between them.

Is there a way to check if the Conax card printed circuit board is in OK condition?

[26fld745t]

Re: Finlux 26FLD745T Tuner (?) trouble

33V at PSU is 34V, and it is consumed on it´s way down to 32.8V at the tuner pin n:o 9, both steady. Dunno if this is within spec..

[tom66]

Re: Finlux 26FLD745T Tuner (?) trouble

That is fine