Entertainment Center: TVs, Stereos, VCRs and DVDs - MARANTZ PV6080, looking for more answers

I have a Marantz pv-6080 CRT projection set that I repaired little over a year ago. At the time of the repair, the CRTS needed to be replaced. I have figured most of the issues out with it, but was curious as to why the HD inputs work just fine, but the SD inputs, have issues with the red coming in and out. Sometimes the picture will be fine, but then it will suddenly lose the red. What would be causing this? Is the module that contains the video processor for the SD side of the set possibly bad? Any ideas would be great. Not sure if I will fix it yet or not. I am currently looking at a good av rx with a good video processor, to simply work around the problem. Thanks for any advice.

Please post back on exactly what inputs your using.

I am currently using only the HD component input, which is set to 1080I. I have also used the VGA input, which works fine, except for the fact that I believe the convergence is in need of correction. But I believe that the VGA input operates off of the same module in which the HD component input does. I experience the problem on the a/v inputs, the s-vid inputs, or the 480P component input. These inputs are all common to one module. Finally, I do experience some convergence drift, which coinsides with the temperature of the display. I feel that this is due to old worn out caps, and am considering pulling out the convergence mod, and sending it off for rebuild, since I found a company that will do it for cheap.

I guess what I am looking for is if we can troubleshoot this down to a modular level. Once this has been accomplished, as I said before, I got in touch with a company that sells and repairs these modules.

Try the tuner input and let me know what you get.So,did you replace the crts or not yet?I can't get access to any service info on this set ,so some pics would help.

Yes, I replaced the CRTS about a year ago. When on the tuner input, I have the problem with losing the green as well. As for the service manual, I still have an electronic copy of the service manual in PDF format. If you would like a copy of this manual, let me know where I can upload it to, or provide me with an e-mail address, and I can send it to you. I work more on the install side, and am pretty rough on the bench side, since its been a while since I have really had to troubleshoot anything on component level.

All of the bad inputs would be using the same video processor.Unless the tuner is mounted on the same board as the A/V inputs ,it's going to be the module thats common to both the tuner and A/V inputs.Follow the outputs of the tuner and A/V on your service manual and they should both go to a common video processor ic.The board the ic is mounted on will be the bad one to have fixed.

ok, that does make a lot of sense, but do you think that the SD side, and the HD side have different video processors??? After Looking at the diagrams that show how all of the mods are connected, it appears that all of the SD jack panels connect to a "gemstar gold panel", in which connects to the small signal board, (this mod has the tuners on board, this mod has been replaced). The HD input panel connects to a "wide band video block", which goes directly to the CRTS. This in turn means that only the SD side uses the convergence panel, and the scan/HV panel. Could it be possibly one of these panels causing the issue?

My bet would be the small signal board since your HD is working fine.

The small signal board was already replaced with new, becasue I thought the same thing initially as well. I also tracked down a video processor on that module as well.

Well, the only thing left is to actually troubleshhoot the problem.How fast do the colors start to drop out after you turn the set on?Does it get worse as the set warms up?

Lets make sure I understand you correctly. What you are asking is that when I turn the set on and switch it to an SD input, how long does it take to lose the red, or it cuts out?? Secondly, when I enter the service menu, (been a while since I last did this), but if I remember correctly, it also flags an issue with the deflection processor, which to my recollection, is located on the small signal board.

I was trying to find out if the problem may be heat related.If the problem gets worse as the set plays longer it would make it much easier to find.How long has it been since the modules were changed out?

It has been roughly 1 year since the modules have been swapped out. But initially when I replaced with a new module, it did not seem to effect the problem at all. I do have some convergence drift issues, which are heat related, but I will have to double check to see if the colors cutting in and out are heat releated or not.

Well, I finally got some time to sit down and do a little more troubleshooting on this set. It seems that when it is first turned on, I put it on the tuner input, and it did not have any red at all. Every once in a while, I would see some red lines flicker on the display. It looked something like retrace lines. I am currently letting the set warm up to see it that changes anything. Upon entering into the service menu, it flagged the video processor, and the deflection processor. According to the service manual, it states that "The second line displays a string of letters (FG) identifying those subsystems which could be present but did not
respond to the microcontroller commands (via the I2C Bus) when the service mode command was first acted
upon." In my situation, the string of letters are (EF). E is the video processor, and F is the deflection processor. I am not sure if this would be considered as a "Problem" or not. Thanks for your help.

Now, after leaving the set run for approx 2 hours, I now have blue, bur lost green and red. The red will come in and out as it did before, but now no signs of the green coming in and out. I am doing this testing on the tuner input.

Just buy a can of "chill" spray and spray the components on each module after it warms up.The module that causes changes in the picture will be the bad one.