|
| DOA or close to it. This tv was bought by a relative who failed to use it. Bought last year about july. I think it got turned on once or twice. 90 day warranty expired. Magnavox said to bad, buy a new one. plugged it in and red lite came on. Thats all. Push on button= nothin. Took off case and nosed around. Ac ok up and thru rectifier. 16 volts leaving board thru main connector. Seems to me whatever is supposed to hot up the circuitry is not working. Would have to be something large as tv is supposed to use 40 watts. Not that many active devices on the power supply board. psp472152080
model 19mf337b/27.on/off ohms ok. Seems to me there ought to be something here to short out to turn on tv. It would make a nice computer monitor. Am pretty fair with electronics, but without a schematic, I can only guess by following the circuit runs, and I ran outa guess's. Any one got any thoughts?
|
Follow-Up Postings:
|
- Posted by thetoolman (My Page) on Thu, Oct 23, 08 at 9:06
| Jordon, I have the exact same model, with the exact same problem. If I find anything out I can let you know, please do the same for me. I just started with this project so I'll try to keep you up to date on developments. Have you found a schematic yet? Thanks |
|
| still ain't found a clue, but I ain't given up |
|
- Posted by thetoolman (My Page) on Thu, Nov 6, 08 at 14:43
| Jordan, I haven't given up either. Lately I haven't been able to work at mine because of other priorities. What I have found out so far was the Red LED is an indicator of the monitor being in a "Stand By" mode. The power supply board seems to be working as it should, it feeds +16 VDC to the main processor board. On the processor board is where the other voltages are created. I have noticed that these voltages are controlled by the main processor that is a BGA with the heat sink attached to it. My fear is the company used "leadless solder" and IF there is a poor solder joint on the BGA main processor, there's not much we can do. If that is the case,......... it's checkmate my friend. But I haven't come to that conclusion yet. I was able to buy a schematic with diagrams from Manualzone.com . I spent $25 for the manual, schematics, block diagrams that also includes some pictures or diagrams of what the signals should look like at different areas of the board. As I said I haven't made too much progress yet, I've been really busy at work and at home. I will keep you up to date on any other developements I find. Best Regards! |
Please Note: Only registered members are able to post messages to this forum. If you are a member, please log in. If you aren't yet a member, join now!
Return to the Electronics Forum
Instructions
- You must be a registered member and logged in to post messages on our forums.
- Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review the contents and make changes.
- After posting your message, you may need to refresh the forum page in order to see it.
- It is illegal to post copyrighted material without the owner's consent.
- HTML codes are allowed in the message field only.
- No advertising is allowed in any of the forums.
- If you would like to practice posting or uploading photos, please visit our Test forum.
- If you need assistance, please Contact Us and we will be happy to help.