Ghosting and wavy menus on RCA DLP Projection TV (HD61LPW42)

[SurrealMustard]

precise clarification

no, I ment to just put them in parallel with the one thats on the board but just to try and see if it fixes the problem, if it does'nt then remove it and try it on another one. If it does fix the problem then get the correct cap to replace the bad one.
on the 47 uf ones I would use something smaller, 10 to maybe 100 but not much higher.

So it would be fine to temporarily run the existing (possibly failing) 100uF 6volt capacitors (but not the 47uF ones) in parallel with some 330uF 25volt units?

[R_J]

Re: Ghosting and wavy menus on RCA DLP Projection TV (HD61LPW42)

it should be fine, its always better to use a value thats closer but if thats all you have.

[SurrealMustard]

no go

I tried soldering the 330uF capacitors temporarily into the circuit today, but they just won't stick. They seem to adhere to the edge of the solder pad at first, but then just crack off right away. Bummer.

[R_J]

Re: Ghosting and wavy menus on RCA DLP Projection TV (HD61LPW42)

Are you adding some new solder to the cap that is on the board? You can't just heat up the old solder and expect the cap. leads to stick, also add a bit of solder to the new cap leads (you don't need a big blob, just a thin coat).
You could just get new caps and replace the old ones on that board. I don't know what else to say, It is most likely just one cap that is bad. but without proper equipment (scope) were only guessing.

[SurrealMustard]

Still no good!

Talk about an elusive problem! I eventually just replaced the whole formatter board with a used one from eBay (an FMTR-420 to replace the included FMTR-130) but am still getting the same ghosting, discoloration, and wavy menus. Either I got a defective board or there's a problem somewhere else. Could power supply issues cause this?

[SurrealMustard]

going to do what I should've done all along

I think I'm just going to have to break down and buy one of those inexpensive capacitance/ESR testers from eBay. They can be tested in-circuit without desoldering anything, right?

[SurrealMustard]

Capacitor tester is here!

My capacitor tester/ESR meter is already/finally here, so I started measuring the capacitors on my original formatter board to see what we were up against (test results of the replacement formatter board and the power supply are coming later on). What I found is that while they are easy to test out-of-circuit, it is difficult to do in circuit because two hands are required just to hold the leads and one extra to push the test button, so some creative techniques had to be used, but the job got done.

The results were anything but what I expected. Either I did this completely wrong or there are some components in parallel with the capacitors complicating the result. Almost every capacitor tested with a μF measurement that was significantly higher than what the component was rated at and an astronomically high ESR reading.

The measurements are annotated into the attached picture. Can anyone make heads or tails of this?

[SurrealMustard]

More test results

I tested the replacement board today and got similar erratic and inconsistent results. An inspection of the power supply board revealed somewhat more consistent (and uneventful) results, however I did find a leg of a capacitor on the power supply board that was loose and looked like it had missed its turn on the solder machine at the factory, so I'll touch it up tomorrow and see if that makes any difference.

[SurrealMustard]

all out of ideas

Added solder to the leg of the capacitor on the power supply that was missing solder, but still no dice. I'm really not sure where to troubleshoot next short of removing all those capacitors on the formatter and testing them individually, but seeing how high some of the ESR readings were, it would make sense that there might be something the matter on there. I think I'm just going to attempt to return the replacement formatter board that I bought and find a new one, unless someone has any other tips because I'm all out of ideas.

[SurrealMustard]

bad caps!

All right, now we're getting somewhere. This morning, I used the heatgun to remove all of the questionable surface mount capacitors on the formatter board and measured them individually out-of-circuit with the capacitor tester/esr meter and got some proper results. I found that capacitance was within protocol for all of them, but ESR seemed a bit high. I got 5.8 and 8.8ohm on the 100uF caps in the top right corner, 23-52ohm on the 100uF caps in the upper middle, over 100ohm on almost every 47uF cap, and 140ohm on the 100µ in the center.

Am I correct in my understanding that ESR readings over a few ohm indicate a bad capacitor? If so, it would appear that I have found the culprit - that is almost every capacitor on the board that I didn't replace.

[SurrealMustard]

Fixed!!

At long last, the saga comes to an end. After replacing the defective surface mount capacitors, the ghosting and distortions are gone. It only took two misdiagnosees, seven weeks, a capacitor tester/esr meter, a defective formatter board to throw me off the scent, and some new surface-mount capacitors from mouser to get things working (for the record, those things are really tough to solder with a dull iron, especially when there's other components closeby).

Thanks to everyone for sticking with me!

[R_J]

Re: Ghosting and wavy menus on RCA DLP Projection TV (HD61LPW42)

Good to here you got it working.
This is where a Scope is very usefull, just check what is on each capin question and see if its doing its job, if it's not then just replace the bad one. simple, maybe a 1/2 hour job.

[SurrealMustard]

Surprise ending

Good to here you got it working.
This is where a Scope is very usefull, just check what is on each capin question and see if its doing its job, if it's not then just replace the bad one. simple, maybe a 1/2 hour job.

For sure. And as if the whole experience wasn't interesting enough, the replacement lamp I bought actually managed to burn one of the lenses inside of the light engine, rendering it useless. The happy ending is that the lamp store was willing to make it right and will replace the whole light engine with a like-new unit that doesn't have a decade of dust built up or a noisy color wheel, so this set will be fully brought back up to spec in that way also. Talk about a comprehensive repair!