CurtPalme.com Home Theater Forum

[dvh99]

[draganm]

[dvh99]

and, any progress?

you guys are sloooowwww .

[draganm]

[Nashou66]

Yeah I haven't ordered the parts yet. Drags will definitely get to it before i do. And I still have the Banding mod to do to my own boards. Arrgggg!!!!!


I just hired a new cook so I might have some more time, hopefully business will pick up, if not, I'll have time but less $$$ because of the new hire.

Athanasios

[dvh99]

let`s hope this 1 can keep his hands out of the till.

[Bodi79]

Hey Guys !

After a few days of holiday i assembled the marquee again today (after modding everything) and fired it up.

The good news.. no more high pitch noises etc.

The bad news.. i cannot get the Marquee sharp anymore.

Did a complete reset, tried setting everything up again from scratch without any luck.

One thing i noticed, if contrast is lower than 25 the image is somewhat sharp.
As soon as i get over 25 it´s getting unsharper and over 30 it really bleeds.

Any suggestions what of the mods could trigger something like this ?


What i modded:

-Focus Board Mod (front to back everything one thing i didn´t add were the inductors coudn´t get them in time)
-VNB (front to back everything suggested)
-HVPS Mods (aswell every component swapped as suggested)
-Convergence Board (same as above)
-VDM (same as above)
-CLM (replaced C2/C1/C6/C7 with the caps suggested , did not replace the tantas cause the weren´t on stock)




Thanx for any suggestion

Ronald



P.S.: Stupid me should have tried one board after another but what can i say..

[Nashou66]

Id check the HVPS with another spare if you had one. That is why I always do a few changes and test. doing a complete overhaul at once when you have not test each change makes it hard later to pin down what change might cause a certain issue, unless you have another set of stock boards to swap out. But bad focus might be a low G2 voltage due to rester change. If you saved the old restores from the HV measure them and see what they are compared to their markings. I found mine were from 560 to 680 and putting the original value of 560 caused issues. re ordering 680 values fixed the issue, i know this makes no sense but it is what I have observed.

Athanasios

[Bodi79]

Happy New Year to everyone !


@Athanasios

I don´t have Boards to swap but could isolate it somewhat.

Resoldered just for testing the original 6x 560k Resistors back on the HVPS .. no go same issue.

But if i start the Marquee without the Focus Board.. i have Focus back.

So my question is can it be some of the newer caps?

As suggested i replaced them with the 1000uf higher voltage Caps and the 470uf on the side with low esr aswell.

And offcourse swapped the Motorola chips with the Tle2074´s.


Thanx again
Ronald

[Nashou66]

Hmm, you might have blown the some of the 9 Mosfet's that rune in the middle of the board. Can you see if you have focus with any of the different internal resolutions from the menu?

What you do is put up a grid and go into the input menu( i think) and change the internal resolution and note which resolution if any are in focus. if so then it will tell us which mosfets are blown. The Focus board switches different film caps in and out of service for different resolutions trough these mosfets.

Athnaasios

[Bodi79]

@Athanasios

Well with the Board in place i don´t have any focus on any tube (or any grid).

If a mosfet would be blown at least one tube should focus. (i guess)

Just to be sure i resoldered 6x 470uf Caps back on and even the 2,2uf 250v back on..
Same issue.

Only component i didn´t put back is the TLEs (cause the motorolas wen´t in the bin) and even if one of the
TLE´s were damaged all 3 would be unlogical.



Btw. if i remove the Focus Board Green Focus is perfect / Red is okay/ Blue out of Focus (but that may be cause i didn´t correctly align everything after setting it up again a few days ago.


Thanx again
Ronald

[Nashou66]

Right Ronald, but I found that those IF520's can blow, all 9 at once or at least one of the resonant frequencies.

There was a way to test by shorting out the legs ( Source to Drain) to switch in the cap. So put the FCM back in and first try the internal frequencies one at a time, you might find the lower ones will focus but the middle wont and then the upper ones will.

So for example on the red channel Q113 is for the lower frequencies, Q114 for the middle and Q115 is the highest frequencies.

So to test you could set it for 1080p@60 and short out Q114 i believe. This would then put C119 into circuit for that frequency.
You would need an extender board to do this though or solder a jumper wire on the underside for easy accuses .

Scott led me through this before, i lost the text but from memory and reading the theory of operation manual I think I have the
method for testing correct.

Athanasios

[Bodi79]

@Athanasios

Thanx for youre help again.

I don´t have an extender Board..

But i will try setting a higher resolutions to see if it makes any difference.

Will search if anybody has a spare focus board for cheap so i have something to swap out.



Ronald

[draganm]

ok, first step on the Cree HDM mod. I must say I have a lot of trouble with the fact that the circuit is drawn nothing like it actually looks or is physically layed out on the board. I think the Diode's are facing the right way though. Red line is for a jumper I added on back side. Yellow lines are board traces I put on for reference.

[dvh99]

don`t connect anything, the diodes are pointing in the wrong direction.

don`t forget u12 and u1.

and replace c6 with a 2n2 (2200pf) if you are going to use q5 and q7.

[draganm]

[draganm]

ok, got it all done including both u1 and u12 drivers. Everything except for the 24VDC splice/jumper.

[dvh99]

despite the fact that these fets will run cooler they do require a heatsink .

[draganm]

[Nashou66]

DRags you need to make yourself a couple extender boards buddy!!!

Athanasios