Insignia NS-LCD37 - One Second to Black - Another one

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Pic of main board and inverter board:

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

As you thought pictures are useless . You need to state the ohms test in ohms 2.2 is not sufficient. Do you still have sound - a dvd film playing is good.
On the inverter board there will be some small fuses have you tested them.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Thanks for your response. I will try to get better pics. On the ohms test, I tested T1 thru T8 across top and bottom left and then right (S1-S2, S3-S4 I think), with meter set to 200K ohms it read 2.2. Did I not do that right? I did just unpack my dvd player and am looking for a dvd to play, then need to figure out how to switch the input menu without being able to see it. For the fuses on the inverter board, if they are labeled F1, F2, and F3, I tested those for basic continuity, how else should I test them? Please let me know. Thanks!

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Well, I tried playing a DVD and as I suspected, without seeing the screen I can't tell for sure if the input was set correctly. I also tried connecting the HDMI cable from my cable box to the tv and nothing, no pic or sound, but again, without being able to see I don't know if the input is correct. So, before I go ahead an pull it all apart again, any recommendations on what to test next? I'll try to get better pics at that time as well. Thanks for any help you can provide.

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

For the transformer test meter should be on ohms 2000 and if that goes off scale then use
ohms 20k. Fuses continuity is sometimes ok if is shows on screen if you are relying on beep
sometimes not. Best to use ohms 200 -it should be the same result as holding the probes together.
With the dvd you set it going then blindly go through the source select sequence until you hopefully hear something. if that doesnt give a result try pressing mute then do it again.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

It sounds as if I did the transformer test correctly as I followed instructions from previous posts and got the same 2.2 reading that indicates they are good. On the fuses, yes, same result as if I had touched the probe leads together so those sound good as well. For playing the dvd, I tried going thru each input but did not hear sound. I'll try the mute button but I think if you press Vol+ it usually unmutes if it had been muted, but I'll try it again. So given that, what would be next to test while I have it apart? Planning to take it apart tomorrow evening so I'll post more than. Thanks again for your help!

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

I dont think I have ever told anyone to use OHMS 200,000 to test these.
Normal is 2000 ohms I have only seen two or three cases where it has had to be 20,000 ohms. Problem is I dont know at what point your meter decides it is 2200 ohms. at 5% it could be 1991 to 2309 which is just not accurate enough.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Please bear with me, this is the first time I'm trying this level of repair. I'm very comfortable with swapping boards but I thought after reading these threads that replacing a transformer would be good for a firsts time board solder. That being said, I'm pretty good at following directions, so if in the posts the meter should have been on 2000 ohms I would have set it that way. However I performed several tests switching back and forther between ohms and dc volts and when I wrote the post later it was from memory, which we all know gets better with age . I won't have time to take it apart tonight but will get back into it tomorrow and I'll recheck all the transformers as well as F1, F2, and F3 fuses on the inverter board. I'll see if I can get better pics as well. I'll also recheck all the dc volts on the cables from the power board. Not sure what to check on the main board or what else to check on the inverter. I'm welcome your suggestions and appreciate your being patient with me.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

I took the inverter board out and checked all. What I have is 8 transformers labeled T1 thru T8. Each transformer has 8 leads, 4 bottom labeled left to right 1 - 4 and 4 top labled left to right 8 - 5. I measured bottom left to top left and bottom right to top right (1 to 8 and 4 to 5). All measured with meter set to Ohms 20K.
T1 1-8 = 2.24 4-5 = 2.24
T2 1-8 = 2.23 4-5 = 2.24
T3 1-8 = 2.22 4-5 = 2.25
T4 1-8 = 2.25 4-5 = 2.24
T5 1-8 = 2.24 4-5 = 2.22
T6 1-8 = 2.24 4-5 = 2.21
T7 1-8 = 2.23 4-5 = 2.28
T8 1-8 = 2.22 4-5 = 2.21
Attached is a pic of T7.
Please let me know if I am doing this the right way.
Thanks.

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Terrible picture - you try deciphering an upside down out of focus number
Anyway you have tested the correct pins and in the main seem ok. Only thing slightly awry
is the 2210ohms on one v 2280ohms on another but nothing major enough to say for certain it is bad. At least that is my interpretation

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Sorry about the pic. Still using my cell phone as I haven't found my regular camera yet. I know it's in a box around here somewhere.
On the fuses on the inverter board, labeled F1, F2, and F3, I used the same setting on the meter (Ohms 20K), when I touch the leads together starts at high number and goes to zero quickly. When I touch those fuses I get the same response. So, if I'm doing that right those should be fine as well, right? What do you think I should test next?
Again I appreciate your assistance!

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Meter should be on 200 ohms to test fuses they should give the same result as holding the probes together. So it could be a main board problem - you could try checking the voltages where mentioned and the voltage regulators. At the moment it could still be anything that is the problem.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

OK, so ohms at 200, F2 = .8, F3= .8 but F1 = 1.4. Leads touched together = .8.
So does that mean an issue with F1? F1 is smaller than the other two fuses and only has the letter "D" printed on it. Looks like I'm spending the weekend hunting down my camera so I can get you some good pics.

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Drat another gray area fuse is borderline - next test would be to check voltage at each side with respect to ground

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Still no luck at locating camera but in the meantime, since power supply and inverter seem to test OK and limited info on testing main board I decided to go ahead and order one which came in late Friday. Well, I installed it and same result. Only difference is one board flashes "Please wait" and other flashes "No signal". So back to it pointing to the inverter board. Since it doesn't look like an easy fix for a first time solder I went ahead and ordered a new inverter board. Should be here Mon/Tues. Thanks for all your help and input. I'll keep you posted on how it goes.

[logonsys]

Re: Insignia NS-LCD37 - One Second to Black - Another one

I installed the new inverter board, tv works perfectly! Unfortunately I didn't get to try to fix the board itself so I'll put away the soldering iron until next time. Thanks for all the info and help!

[selldoor]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Thanks for reporting back pity we couldnt bottom out the inverter board - Hang on to it though you might need a transformer off it in future - or maybe sell/give one to someone
who needs one on here. Seem to be a lot of insignias appearing!!

[hbob17]

Re: Insignia NS-LCD37 - One Second to Black - Another one

Not sure if this will be seen or not since this is an old thread but I also have the ns-lcd37 and the tv will power up flash please wait and then go to a black screen and power off. I have tried forcing the tv to an input on start up checking the screen with a flash light, and it has no video or sound after the please wait screen flashes. I have tested all the outputs coming off of the power supply board and all appear to be the correct voltages. In addition I have checked the transformers on the inverter board and all seem to be at 2.2k ohms. Any help will be greatly appreciated.