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Discussion Starter #1
i recently was given a panasonic with a bad set of ic chips by an elderly friend (eugene). he was going to haul it to the dump but opted to let me have it when i told him i thought i might be able to do the job though i couldn't say for sure. anyway i got home and fixed. it was intended to replace the tv he's using now. it's a crt rear projection also. i thought since this one went so well that i make an attempt to fix the off color semi fuzzy image on his tv. i have tried some adjusting in both the settings menu and dials in the front (focus and screen both). only done this because i was fairly certain someone had monkeyed with the front before. after tinkering, i believe there is an issue a signal going to the green light gun. it doesn't do brown or whites very well. you can also make out some text in the convergence adjustment with the red turn up to though it's just black and what i would believe should be green. i did mange to get it better but it was only done by adjusting a to the point it had a green have over everything. (very noticeable with the blacks but still no green text anywhere). i confirmed this when i removed the back while it was playing and the red and blue light guns had an image but the green was not putting an image out. it was just brightly lit. i have limited knowledge of how these work exactly but it seems to me the green should have an image to. if anyone has any experience with a hitachi 50dx01b 50" or has a general idea of what i should look at or check, it would be appreciated by both eugene and myself. i did look the caps over, all the connections and for open resistors already. maybe the board on the light gun, idk:dontknow:?
 

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Your post has been moved to a more appropriate location to make information easier to find and to make it more likely that others who are interested will find your post.
 

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Post an image of a convergence test pattern.
 

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Discussion Starter #4
thanks, i'll get on that in a day or 2. my cousin from out of town is visiting. i grabbed a calibration disk thing from online. more of a series of mp4s really. i'm gonna convert and burn them to disk though in a lower resolution since i haven't a device capable of 1080. he has a dvd player though. i'll get a series of things up here. including the 100% red, blue and green, convergence and anything else i find that i think might be of some use. i seriously think it's not putting or getting a signal to the green light gun though. thanks for moving me. i started the thread from my profile and really had no idea where it was going lol.

here is what i'll be using;

http://digg.com/newsbar/topnews/Free_TV_calibration_ISO_download_best_free_one_you_ll_find
 

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Discussion Starter #5
update:
he's been out of town the past couple of days for a funeral. i grabbed a freebie magnavox in need of some tlc from craigslist just in case i can't fix the hitachi. for that matter it might need more than i think. after it was loaded, it was shared with me that it was possibly (likely) hick by lighting lol. they said it played but it smelled bad. i tried it when i got home and found a busted and smoking diode on the psu.. this would really be for another thread though so i'll end it there. i'll get the images of the convergence up when he gets back in town though.
 

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If the burned diode is in the primary of the power supply it could be due to an external surge and there might not be much else wrong but if it is anywhere else there is likely a short or regulation problem causing too much current to be drawn through the diode. Be very careful not to hurt yourself or to do more damage when troubleshooting this.

Thank you for thinking of starting a new thread for a new problem.
 

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Discussion Starter #7
update 2:
i haven't gotten out there to get a test pattern up. he's supposed to call when he gets in town. being retired he tends to have a strange schedule. anyway i'm going to try to get it working.. the freebie that i mentioned starting a thread about though.. i couldn't find anything technical but there was a data sheet on the boards and what they are supposed to check as. anyway i got the diode off and it was rough to say the least. after researching the writing on diode, i found a suitable replacement at radioshack. it's working great now with just that single part! idk if it's a good idea to replace a 100v 6a rated diode with a 100v 6a diode but it seems to be working lol.
 

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It depends on where it is in the circuit. If it is just part of a bridge in the primary it is not critical. If it is a rectifier on the secondary it could matter, as switching time needs to be higher for the output of a switching supply than for 60 Hz.
 
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