Jump to content
Due to a large amount of spamers, accounts will now have to be approved by the Admins so please be patient. ×
  • 0
IGNORED

Horizontal not fully opening


Joseman

Question

Good morning!

 

i've a chassis hantarex MTC9110 that drives me crazy. I've tried all before ask, but i'm out of ideas.

 

The problem is that adjusting the variable resistor RV4 (H.AMP) the monitor does nothing, i explain:

 

Two years ago i changed all the electrolytic capacitors, flyback and, ignoring the advices, i changed all the transistors that are in the heat sink area.

 

ok, the chassis worked like a charm, top image quality.

 

After that i set puzzle bobble on the machine to play with my girlfriend.

 

One day, we turn on the machine and all good, but i leave to my room half an hour and when i returned to the machine, the display was shrunk horizontally to a tiny size.

 

I opened the machine and the first failure was the ventilator that cools the heat sink zone, it was stopped. I fix that and leave the machine off for weeks, till 4 days ago... to try to repair it.

 

However i didn't succeed, i read dozens of threads about the subject, and started changing components, i gave it back all the old transistors, changed the flyback. and some many other things.

 

What i made till now:

 

-tried 2 monitors.

-changed the variable resistor board (2x), where RV4 goes.

-changed the flyback.

-changed the TDA1670A

-changed diode D5 and C9 capacitor (i read it somewhere)

-changed the BDX53A

-changed the BU508A

-changed B3 Coil

-changed BC558B (tr16)

-changed C42 capacitor.

 

and NOTHING, the same problem

 

I uploaded photos of the problem (sorry for the quality but i think is enough to see the problem):

 

This is the tiny display, this display stays this way till RV4 is amost to the top-left:

 

http://i68.tinypic.com/110dvko.jpg

 

if i set the resistor to the left, nothing happens till almost the end, then the display goes like this(tries to open starting from the middle):

 

http://i68.tinypic.com/2djniit.jpg

 

and if i set to the left totally, the displays totally open but the imagen is out of boundaries!

 

http://i68.tinypic.com/2hrde7s.jpg

 

 

I really need help, i don't know what to do right now with the problem.

 

Thankyou for all the advices!!

Link to comment
Share on other sites

8 answers to this question

Recommended Posts

  • 0
Check the connections of the impedance adapter with yoke and main chassis as well as all the solder pads involved.

 

hi, thanks for the answer!

 

the impedance adapter is where TH301 goes?

 

if it is this board, i swapped with another from another chasis and the same results, what i didn't do is check the mainboard green connector...

Link to comment
Share on other sites

  • 0
In your last image where you've used the widest horizontal connection, can you bring it in a bit with the horizontal position adjustment (to the left totally) and it's ok? Or is it still out of ratio?

 

Hi,

 

Sorry for the delay on answering, real life you know :)

 

if i touch the RV6 pot with the widest horizontal aperture (out of ratio) it works well and the picture goes to the left or to the right and you can put in ratio left or right.

 

This afternoon i made more changes:

 

Removed C37 (and his friend the blue capacitor that it's at the otherside of the PCB). changed the 2 capacitors for others of an spare pcb.

 

Removed IC2 (TDA2595) and changed for the other of the spare pcb.

 

but NOTHING, the problem is exactly the same!

 

Any idea please :(

 

If i have to change all the components one by one, i will do it... but if anybody can tell me some advice... better! :)

 

 

thanks!!

Link to comment
Share on other sites

  • 0

I googled this once when my chassis did the same (Cheapie chinese chassis)

 

Ended up the width capacitor was the cause. It's one of them red ones. I soldered the new one from a donor TV in parallel to the existing cap underneath the chassis

 

Fixed!

 

Hope this helps

Link to comment
Share on other sites

  • 0
I googled this once when my chassis did the same (Cheapie chinese chassis)

 

Ended up the width capacitor was the cause. It's one of them red ones. I soldered the new one from a donor TV in parallel to the existing cap underneath the chassis

 

Fixed!

 

Hope this helps

 

Hi

 

Thanks for the answer!!

 

I changed all the electrolitic capacitors for new ones... but yes, lately i'm starting to think that maybe one of the new chinese capacitors could gone bad and out of range...

 

I didn't have any red capacitor... in the 9110 what is the width capacitor? well, i will see in the schematic...

 

- - - Updated - - -

 

D13, D12.

 

C36, C37, C40, C41, C42.

 

Hi, thanks for the answer!!

 

I changed all the components you said with the pcb spare counterparts, the problem is still there!

 

I'm starting to think on some electrolytic capacitor...

Link to comment
Share on other sites

  • 0

YES!!!!!

 

I fixed the problem!!!!

 

32 components later :D

 

It was: R88!! it was opened! it hasn't got any ohm value!

 

the problem was around TP9 where the voltages were between 0,54v and 70V (dependant of RV4 position) while on a working chasis were between 1,7V and 48V (with full control and precision of the voltages on RV4 (not on the bad chassis where the voltages between 0,54v and 70v were weird and inconsistent)).

 

this 70V led me to think that or some component was leaking voltaje to this rail or, some resistor was shorted (or with wrong value).

 

with a tester and patience i was comparing ohms on 2 chasis on all the resistors around TP9, when i reached R88, his right leg was giving me weird values while the left leg was ok on the failing chasis.

 

I lifted the right leg of R88 to isolate the wrong value on the 2 chasis and BINGO, the problem was still on the right leg of R88

 

R88 was opened (not shorted) giving no ohm value (the appearance of R88 was almost better than new!!!). I just changed the resistor and the chasis started to work, with perfect horizontal aperture and full control on RV4.

 

 

If anybody thinks that this is important for future troubleshooting of this chasis feel free to share or put it wherever you want!!

 

thankyou all your your help and advices!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...