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Discussion Starter #1
I have a mitsubishi WS-65809 Projection Tv with the v-18 chassis and the dreaded dead set with a 22 blink Code. I have Read thru several Forums and Internet Tips Hoping for some tips to my Problem. I Understand it is a Protect Mode and it is usually the IC's, Pico Fuses, Resistors etc... Please let me tell you what has been done. Yes the Ic's were ordered from MCM the STK392-570's Replaced the Ic's and the two Pico Fuses associated to the +/- 24 Volt Protect circuits FA904 and FA905 were bad and Replaced also checked all 3.9 Ohm Resistors with one Leg out of Circuit Tested Individually with a Fluke 77 DVOM meter Ok. All Solder joints inspected for continuity and No Bridging of Solder Joints on the IC's Checked Several Times and inspected the board for any supicious bad solder joints? Any in Question were Resoldered with no Bridging or solder Splash. Heat Sink Compund applied and Ic's seated Firmly to Heatsink before any Soldering done. Satisfied everything was in good shape installed and hooked up everything. Same Problem Red LED Flashed a 22 Code Only this Time when checking Pico Fuses the -24 Volt FA905 Protect Fuse was OK but the + 24 Volt Potect FA904 fuse was Open?. Checked all connections again No solder Spash, Bridging or anything wrong could be found. After Researching several sites and reading about bad IC's out there I called MCM and they sent RMA another set. Went thru the same thing of Removing and Installing the New Replaced IC's checking Resistors careful Again Soldering and Inspecting with 10x Magnifier Lens and installing Heat sink compound. Installed everything again and same exact result. No Picture or Sound just a Blown FA904 +24 Volt Protect feed Fuse with the 22 Blink code. Frustrated Now I Removed the IC's Completely from the board and replaced the 5A Pico fuse and fired the set Up. Now I have Sound and the Screen comes up but has a Washed out over bright screen that is unrecognizable? I expected to have a Picture Only with a Distorted Convergence Look? I pulled the 2HDW Board and used my ESR Meter and Find that there are Several Caps with a High Reading. Is it Possible the 2HDW Board is causing the FA904 Fuse to open? Or is there something else that comes to Mind? This is where I am at Now? Could the New IC's have been Damaged At all? The TV Never came up untill I removed the IC's Completely and fired it up. then it will Play with an Overbright Screen washed out white and has Sound. Any Suggestions?
 

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It is unlikely that caps on the 2HDW are causing this problem. It is far more likely to be bad caps in the power supply. The washed out pix is a CRT bias, screen, or video level problem and could also be related to power supply issues.

You are correct that you should expect that with the convergence output ICs removed, you should have a normal image (with respect to levels) but with no convergence correction.

Start in the power supply. ESR the caps there, check them for capacitance, and look at the output with a scope to see if it is clean. If you can check it, look for DA on the caps.
 

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Discussion Starter #3
Sorry I don't have the Luxury of a Scope Yet. I won't Harm the CRT's running this set without the IC's? I mean continuing checking this out that way? I know the IC's are Amps. What you are saying is basically start over on the Voltage Checks with the IC's still out? I Had a Problem with the +24 Volt line blowing the FA904 pico fuse dead set. Now it comes up but witha white washed out Picture. I had Prior to Removing the second set of New Ic's I installed replaced a New Pico Fuse and disconnected the VG and VR cables to the Deflection Yokes on board and the High Voltage and the Crt's Light up then decided to Pull the Ic's to ty it that way with the DEF Yokes Plugged back in and that is where I am Now. My Reason for asking about the caps on the 2HDW Board is because some of them are High with my ESR Meter reading and Toshiba is Famous for bad caps on their Hyper Module Board same type of caps that cause major Picture distortion as I know you know this. I have Researched a lot of Info and Forums even this one and One said Mitsubishi suggested the 2HDW Boards over the IC Probems we all Know these rear Projection Tv's are Bad for IC's when it comes to Picture Distortion. So Bottom Line your Experience says I have a Power Supply Problem and If I find and Correct this being over or under Voltage then my Picture should be viewable minus the Conversion Level Distortion untill the Ic's are reinstalled? Sorry I am not a Genius or a Wacked out Retard but am somewhere in between there what is DA on the Caps you mentioned? Like I tell my Kids all the Time you don't know if you don't ask?
 

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Yes you won't Harm the CRT's running this set without the STK IC's. Do you see retrace lines in the "washed out over bright screen"?
 

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Discussion Starter #5
To be honest I really didn't want to run it too long not knowing If i would mess up the CRT's without the IC's in Place even though they are Amps I didn't want to do more Damage than what it has. The Picture was Extremely Clowdy or overwhite with faint traces of colors like something moving characters or something don't know what channel it was on but had sound and High Voltage up and was happy somehing Finally Making some Progress. I will have to get back at it to see what I find and will update you to my Findings. Major Question same set? Is there any way to Test the IC's out of Circuit to tell if they are bad or not? STK293-570's. Will a simple Ohm reading Do? If not what Test is there?
 

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You will do no damage with the convergence amps removed if all else is working properly. The convergence circuits likely have nothing to do with the washed out image. Whatever is causing that could cause other problems if you run it too much, but there is no way to know without troubleshooting the problem.
 

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Discussion Starter #7
I Only had the +24 volt protect pico fuse FA904 that kept blowing and put it in protect mode. I will be checking all Voltages with the IC's out and concentrate on the +24 volt line. You mentioned to check for DA on the Cap? Please explain what is this?
 

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Dielectric Absorbtion. This is a measure that will often identify failing caps in these circuits before others and can create some strange effects.
 

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Discussion Starter #9
That makes sense but what do you mearsure or check that with? i have one of those Digital Blue Meters the knock off of the Dick Smith ESR meters. what are you talking about checking the DA's with? is this something Only a Scope can Identify it with?
 

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DA can be measured by charging a cap to its rated voltage or near to it, then discharging it through a resistor, then measuring the residual voltage that returns to the terminals of the cap after the resistor is removed. This must be done out of circuit, of course. Another term for DA is battery effect and it should be less than about 15% of the voltage applied.
 
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