Motorola ts907 low hv

[timmy]

Originally Posted by Yamamaya42

the AC current path of L42 was the reason for looking at the resistance of pins 1-5

http://suzaku.live-evil.org/L42.jpg

not really sure why it's hot if both FBT match, but this may be related to why the 100k ohm resistor burned in the first place.

I had a silvertone that burned the resistor also. Is there a possible reason for the hot L42 from either the horizontal centering circuit or hv regulator like a bad cap. The centering boarders pin 5. Other then that would you use this flyback with the specs it has and the donut 585ohms.

[timmy]

C99 shows.25 but what came out was a .5 this shouldn’t make a difference unless I messed up.

[timmy]

Well it’s official I put the wrong cap in c99 I put a .5 in instead of .25 I don’t know if this may cause the L42 issue along with the video issue

[Yamamaya42]

Originally Posted by timmy

Well it’s official I put the wrong cap in c99 I put a .5 in instead of .25 I don’t know if this may cause the L42 issue along with the video issue

Which would have caused the pulses to be 2x higher then they should have been at that coil , you may want to test r136 too.

[timmy]

Lucky I saved all the caps I changed and there is only one .25 400v c99 and that’s the one I put was wrong. Hopefully the L42 will be ok now and maybe I’ll get video because the pulses pass v6.

[timmy]

Well sorry for driving you guys crazy but it’s not a mistake the .5 is next to the .25 I looked at the wrong one my glasses are not working for me. .25 is in place and checks good. Back to square one again.

[timmy]

I don’t know if these new caps these days are any good but the original cap checks better then the new so maybe I should try the original cap it’s +20% and see what follows.

[Yamamaya42]

Originally Posted by timmy

I don’t know if these new caps these days are any good but the original cap checks better then the new so maybe I should try the original cap it’s +20% and see what follows.

if the OLD is paper, do not trust it.

now the question remains, is the IF problem still there or not?

I'd guess it's a 50/50 chance.

[timmy]

The 10ohm resistor is 11.3ohms

[timmy]

If I only had an idea what it is that tunes the focus coil. All there is focus coil L42 .25 cap 10 ohm resistor that’s it.

[timmy]

The old cap is those dark red ones. I have to concentrate on this focus issue before getting back to the IF because the L42 is going to burn up then I’m screwed.

[timmy]

The IF problem is still there

[Username1]

If you are so worried about the L42 Temp. then just put a 10 Ohm 10W resistor in
series with it, and check it's temp. and move on till you get a pic on the screen
and then you can figure it out.... I mean like a Good Pic from the tuner
with everything else working.....


I also doubt that any cap. that you replaced where the value is .1 and you put
in a .5 by mistake is causing all these problems... I hate the idea of using a
parts cannon on all these tv's before you get it working by only replacing
electrolytics, but that's what you guys end up doing....

This should be your main focus:

Every TV without a signal should produce snow on Picture & Sound
this one does not. You tracked the signal loss to a specific area, & now
need to focus on why it's getting lost. IF Amp not working? IF amp
turned off because of some AGC Fault?



.

[timmy]

Originally Posted by Username1

If you are so worried about the L42 Temp. then just put a 10 Ohm 10W resistor in
series with it, and check it's temp. and move on till you get a pic on the screen
and then you can figure it out.... I mean like a Good Pic from the tuner
with everything else working.....


.

I thought of doing that but there’s a reason why this is happening and I really wish I could get to the bottom of it then move on to video maybe this problem is related to the video problem.

[Yamamaya42]

Originally Posted by Username1

If you are so worried about the L42 Temp. then just put a 10 Ohm 10W resistor in
series with it, and check it's temp. and move on till you get a pic on the screen
and then you can figure it out.... I mean like a Good Pic from the tuner
with everything else working.....




This should be your main focus:

Every TV without a signal should produce snow on Picture & Sound
this one does not. You tracked the signal loss to a specific area, & now
need to focus on why it's getting lost. IF Amp not working? IF amp
turned off because of some AGC Fault?



.

I agree with adding this resistor, you should also stick on the ceramic heat sink using thermal conductive epoxy as I mentioned, save the coil as best as you can.