Riddled TV Repair Forum

SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

I have it mostly disassembled (to the point that I can take the board out to desolder and resolder new STK392-010's in place. I have just a few things hanging on still (I've been taking pictures of every connector before and after I remove them so I can get things back in the right spot.

However, before I unhook these last connections, I wanted to ask some questions.

This is where I am so far.

There is a read wire and a white wire coming out of something (possibly transformer?) It also says "focus" and something else on the side, but I don't remember what it is. It looks like it covers some screw heads or something for adjustment. The red wire runs up to a capacitor (I believe)

It is the bottom one in this photo

and the white wire runs to a board near the front of the TV.

I'm not sure how I'm going to physically get to the other end of the white wire. Before I unhook the red one I want to know what precautions I should take etc.

Thanks again!

Google

kuhurdler · Joined: 28 Dec 2006 Posts: 2879 Location: Overland Park, KS

I'd recommend that you NOT disconnect them if at all possible. Just pull the plastic tray back and rotate it 90 degrees. Then you should be able to desolder the old chips.

SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

Are they special one time connect connectors, or are you recommending this out of safety etc? It seems like it'd be much easier for me to work on the board at my work area.

kuhurdler · Joined: 28 Dec 2006 Posts: 2879 Location: Overland Park, KS

Just recommending it out of simplicity. The less you remove, the easier it is to reassemble. I prefer to leave as much as possible connected. I loosen all the cable ties and then Flip the bottom of the board towards me, and then I throw a throw-rug on the ground and sit and work on it on the floor.

Jesse Mack · Joined: 22 May 2008 Posts: 600 Location: The Last Frontier

This unit does not have a plastic removable tray that the boards are attached to.
The pink wiring harness on the left edge of the board has release tabs on the left edge of the harness connectors (disconnect from the signal board) and are physically positioned as to prevent incorrect reassembly. As you can see from the center picture there are release tabs that is duplicated on the opposite side of the wire. These red wires are second anodes that self discharge when set is turned off. they pull straight out after releasing tabs. the white wire is easily removed by removing the front of the cabinet and removing the access panel. The board itself will slide out and away after disconnected. you need to make sure that all of the ICP fuses are intact or after reassembling the problem will not be corrected. Make sure you watch the temperature of the heat sinks for overheating as this model has a history of the DCU failing causing the convergence chip failures.

Hope this helps

Jesse

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SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

MANY MANY thanks Jesse.

Where/how do I check the ICP fuses? The only fuse I see in the unit is the one on the small board to the side where the power input is.

SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

Also..

With the name of a "access panel" I imagine it comes off relatively easily? Do you have to take the upper shell off to remove the front? I can't figure out how to take the front panel off... I haven't taken the top plastic housing off yet, as I'm not sure if this will be needed? All of the little connectors that jump right over board to board have been removed etc.

Jesse Mack · Joined: 22 May 2008 Posts: 600 Location: The Last Frontier

I believe that the grill cover simply pulls off and is retained by plastic posts pushed into plastic bushings mounted on the cabinet.

I looked it up after that last posting and there are no ICP's that pertain to the convergence IC's on this board. There are however multiple fusable resistors RZ123~128 and RZ142~147 in quadrants H-G/4-5 marked along the edge of the board. They are all 3.9 Ohm 1/2 watt resistors and you will probably find one or more bad. They usually are standing on edge I believe for this model.

Hope this helps

Jesse

SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

Wow, thanks for the great info. I found the resistors and have located their leads on the underside of the board and will test them.

I think I owe you guys a beer or a donation, or something regardless if I get this TV working again or not.

SnakesAndStuff · Joined: 08 Dec 2009 Posts: 38 Location: Jonesboro, AR

All of the resistors on the board mentioned seem to be in pairs, in parallel.

I got 2.2 Ohm reading on all of them except for RZ142-43. Will a blown resistor look bad? I notice the resistors are blue, does that mean they are fusable resistors and should be replaced with such to prevent fire hazard?