Broken Tv :(

[steptoe]

right, here we go again,

the little lads TV suddenly stopped working yesterday,  TV&DVD combi,

it was a cheapish TV we got him for xmas 2012, but Id have liked more than 13months out of it,,,,,,

powers on into standby, the red stand-by LED lights up,

inserting a DVD/CD and it spins up,

pressing the power on button [or any button] does nothing, remote = nothing,

all the voltages from the power board match up with the markings ,

the stand-by LED just stays continually lit, it doesnt flash or anything.

Make  -  Alba

Model -  ASELKDVD1988

google isnt really turning anything up for me,   :|

thanks

 

[OnOff]

Found this on the net for a Bush. Bush & Alba are sister brands (used to deal with their place along the A13 would always give me schematics for anything I asked for for FREE!). Anyway this is a "try" for a Bush TV, nothing lost:

- Press and hold the on/off button

- Whilst holding unplug from the wall

- Continue holding for 30 seconds

- Plug in whilst continuing to hold the on/off button

- Continue to hold for a further 30 seconds

- Screen MIGHT come back on

 

[steptoe]

ah, that makes sense,

it came from argos too,

I'll try that now, good to know alba and bush are the same,

 

[OnOff]

ah, that makes sense,

it came from argos too,

I'll try that now, good to know alba and bush are the same,

Well they're both cr..! :lol:

I remember having to fix a mate's TV years ago that was seemingly branded but made specifically for comet in Spain (the brand escapes me). It had dry joint upon dry joint and that's all it was!

(The daft question is are the remote batteries OK?)

 

[steptoe]

well, that didnt work,

batteries tried from another remote, but should work off the buttons too,

yer, cheap and cheerful often = dyslexic fish, 

do these things come with an inbuilt self destruct for when the warranty runs out.???  :|

 

[ProDave]

My money is on duff electrolytic capacitors in the power supply.

Look for the part numbers on the boards, it's more than likely a Vestel chassis and most service information is available.

 

[Sidewinder]

Check the Caps & PSU first.

 

[OnOff]

As per earlier PM view the caps from the side for slight doming sometimes rather that a full blown split on top.

 

[Sidewinder]

SOGA is a good point TBH, there have been test cases, but, you would need to look them up, a 1 yr warranty has been deemed inadequate in court IIRC!

 

[steptoe]

the TV cost IIRC about £80 ,

its not a massive thing, just would be good to get it sorted,

it was an impulse buy by the missus when she saw them on offer, [too good to miss],

I suppose this is what happens when you buy crap,

I'll pull the cover off and have a look for board numbers, split caps, etc.caps look ok on top, no bulges apparent.

as said, all voltages appear to be OK, maybe I need a fancier multimeter, [Fluke 77 ]

 

[revjames]

sounds very similar to my recent experience with a 'hanspree' (read as cheap crappy chinese TV) turned out to be a 20p schottky diode!

 

[Sidewinder]

Steps a 77 is fine.

Check the ripple on any of the dc supplies though.

 

[steptoe]

PSU  -  LKP PL082

main board  -  HK-T.SP9202V03

any use,?

tbh, I fairly clueless with this stuff, everything physically appears to look ok,

Steps a 77 is fine.

Check the ripple on any of the dc supplies though.

they appear ok,

when I put a CD in it just continually spins as though it is actually playing, and the voltages are stable, the DCs coming off the power board that is,

one thing, there are 2 terminals not marked for voltage, they are marked as  'ADJ' and 'ON/OFF' , I'm getting 3.5v on these to GND,

no idea what they should be, the 12v and 5v terminals are showing just that.

 

[Sidewinder]

PSU  -  LKP PL082

main board  -  HK-T.SP9202V03

any use,?

tbh, I fairly clueless with this stuff, everything physically appears to look ok,

OK, does this look like the PSU?

Does this look like the main board?

 

[steptoe]

OK, does this look like the PSU?

Does this look like the main board?

yep, thats them,

I suppose I should have posted the pics up,

do you want pics of the other side? only a few little SMDs tbh, and the markings for the terminal outputs

that diode, top right of PSU, marked ZD,,,,,

on reverse polarity, nothing,  on correct polarity Im getting a short 'beep' [ie, continuity] then quickly rising to 0.334 ,

diode/continuity setting on the fluke 77

I initially thought maybe a cap was being charged, is that possible? or does it show as a faulty diode? [after what the rev said,,,,,]

 

[Sidewinder]

OK looking at PSU, the "HOT" side is the LV side, the cold side is the ELV side, well normally!

You have 2 x step down Tx's and 2 x bridge recs, some smoothing caps on each, a fuse in the bottom LHS.

You have two transistors and a couple of inductors.

TBH the most unreliable bits are the fuse, the electrolytics, the transistors, the transformers and the inductors, pretty much in that order.

There may be a zener in the top RH corner, I can't make it out, that would be another to test.

I can't make out what the 4 leg chip is bottom centre though TBH.

 

[steptoe]

correct, hot - LV  cold - ELV

4 leg chip bridges across hot/cold,

L1221 817 B W  from what I make out on it,

would I need to desolder one side of that zener, [see above post] to test it properly?

I suppose that even though the voltage is good, the current could be down?

 

[NozSpark]

Could the 4 legged chip be an opto transistor??.....

Looks like that kind of thing to me

 

[steptoe]

OK, Im going to desolder the diode and try testing that,

looking on the track side it appears [to my limited knowledge anyway] to be feeding/connected to the LED-  of the display connection,

 

[Sidewinder]

I suspect it is an RTC/calender being an L1221, but, without seeing it is is difficult to tell!