-
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic. -
Re: 700G no backlights
I can tell that is not what you expected, so I did it again. The meter is set the same as when testing the MOSFETs. Same results. I attached a pic of my tester in case I did not get your instructions right.
I am packing for vacation to the mountains in the morning, so if you don't hear back from me for a week or so, don't worry! If you do get back tonight I will try and check...Attached FilesComment
-
-
Re: 700G no backlights
You learn very well, Grasshopper. While I'm not absolutely sure that your DMM is ''fast" enough to read that frequency, I'd have to say evidence is pointing to a defective BIT3193. If you want to be super secure before ordering one, I've sketched a 'peak voltage adapter' that will determine the peak voltage pins 8 and 9 of the BIT9139 reach.
PlainBillAttached FilesFor a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.Comment
-
-
Re: 700G no backlights
Back from vacation. If you like the outdoors and mountains, I would recommend Glacier National Park - beautiful, great weather, lots of wildlife!
I had a spare BIT3193g on another board and swapped it out. Now jumping directly to U301/2 I see:
1 = 0v with lcd off and on
2 = 0v, then when turn it on it will go to .03v, then back to 0v
3 = 14.5v, when turn on it goes to 17.3v
4 = 14v, on goes to 16.5v
5-8 = 10v off, up to 13v when on
So I am finally getting power to 5-8, but lost voltage on #2
Checking pins 8 and 9 on U303 I get the same .03v as on pin #2 on U301/2.
Pin #5 on U303 is Timer, and goes to 4v. #15 is ISEN, which says open load situation if less than 1.3v, and I read about .5v when on.Comment
-
Re: 700G no backlights
I found some BIT3193g's online for under $10. I will update after receiving and testing them.Comment
-
Re: 700G no backlights
Tried the new BIT3193 and got the same results as the previous one I swapped out... I am officially retiring this one to the re-use pile. Thanks to everyone for the help, and I have three more BIT3193's if anyone needs one. Just pm me and I will send them out.
I do have an increased interest in an oscilloscope after this thread, but will have to do some more reading as I know nothing about them, other than they can be helpful in diagnosing where the problems are. I have a search set up on craigslist but not many in my area at the moment.Comment
-
I just got this tv today and it appeared to have no backlight on. After taking off the rear cover and checking again in the dark I can see that MAYBE one quadrant is lit.. But still it's quite dim. I was going to check the LEDs with my tester, and I found LED 1 and LED 2 + pins on the wire from the inverter, but I couldn't identify a ground. Nonetheless I tried using a mounting screw on the inverter board and also the chassis as ground but regardless my tester reads 300 which is what it reads when there is no voltage draw.
I don't know how exactly to test the inverter itself. Is it... -
I am working on a backup phone to VHF paging solution. Basically I am dealing with the old Zetron pagers. Here is how it works: One calls a number, the Zetron picks up, operator punches in the DTMF access code, the Zetron keys the transmitter and you can talk. press # the Zetron unkeys the transmitter and hangs up / times out.
Now this setup works good on the old land lines, but not at all using a VOIP ATA.
You can call all you want and swear like a bastard at the Zetron, but it will not (even if I threaten it's life) pick up. 
Yep, I know about the high ring voltage... -
Hello, I came here after finding some similar questions asked on other monitors and hope someone here can help me get an ancient Viewsonic VP230mp (23" 4:3 LCD) back to working condition.
First a little background, I have a background in computer and electrical engineering, and I'm smart enough to know I know nothing about LCD displays and how they work. For this topic I'm as green as they come.
When the display is turned on the viewsonic logo displays in the uppper left for 2 seconds then the screen goes black, the power LED is green (on) and when a computer is connected... -
I have a tripp-lite aspint 3636vr inverter charger which blow some of mosfet transistors. I replaced them repaired also the driver circuit and tested but the mosfets burn again.
It work very well as inverter and also as charger if I let the rear switch in auto mode (inverter) and charger only(charging) but in auto when I connect the feed line 220V AC first time it pass ok to line and start charging the batteries but when I remove the feed line it pass to inverter mode and if I do it again the second time when passing from charging to inverter the Main transformer start making a...03-06-2023, 07:07 AM -
Hello, I have a problem with my Samsung UE48H6410SSXZG with the main board BN41-02156A and the power board BN44-00709A. Everything seemed like this, the TV could no longer be switched on, the standby LED always flashed 5x2 times. Backlight was off and no sound from TV. Also made the flashlight test and there was no picture.
I made the following tests:
1. Disconnected the main board from Power Board = backlight works.
2. Connected the main board and disconnected the T-Con = backlights does not work.
So I ordered a main board from Ebay also BN41-02156A but from...
Comment