CurtPalme.com Home Theater Forum

[ben12345]

Hi All,

I've had my BD 800 now for about 6 years, being used as my main 'TV'. I've put about 3000 - 4000 hours on it, witn no real problems other than a duff SMPS board, which I swapped out with my spare projector.

Now i'm moving up to higher definition source material, i've noticed that the image is a little soft, almost as if the focus is out. I've heard that this is a problem on some of the older Barcos running higher resolutions.

Is there any modifications that can help sharpen the image up a bit? I've heard that the Barco 801 RGB amps, switcher and driver can be swapped in to gain 75MHz bandwidth.

Would recapping certain boards help?

Cheers,
Ben

[Curt Palme]

You're most likely seeing the limitation of well used ES focusing tubes. WHen the tubes have under 3000 hours on them, they are literally as sharp as EM focusing tubes. Assuming you got the set used, it had hours on it when you got it, and now that it has 4000 hours+ on it, the tubes themselves are a bit soft as compared to when new. All you can do is make sure that your focus and astig settings are bang on, if that's too soft for you, it's time to move to an EM focusing set.

Cheers!

[Curt Palme]

You're most likely seeing the limitation of well used ES focusing tubes. WHen the tubes have under 3000 hours on them, they are literally as sharp as EM focusing tubes. Assuming you got the set used, it had hours on it when you got it, and now that it has 4000 hours+ on it, the tubes themselves are a bit soft as compared to when new. All you can do is make sure that your focus and astig settings are bang on, if that's too soft for you, it's time to move to an EM focusing set.

Cheers!

[ben12345]

Thanks Curt,

So say i'm watching a DVD at standard definition via the RGBs output of a DVD player, this looks a hell of a lot sharper than the same DVD being played back via my HTPC at 1360x768 or 1440x900.
It seems to have always been the same though, when I got the set, it was only showing 1500 hours.

I also have trouble with convergence at the edges at these higher resolutions, despite adjusting the lenses with shims to suit my installation.

Any other ideas?

Cheers.

[Curt Palme]

Well, the set being 18 years old has a lot to do with that as well (Poor convergence issues in the corners/edges)

You can try recapping if you want. Change only 5 or 10 caps at a time and turn the set on to make sure you haven't damaged anything so you can easily retrace your steps.

Kal said it did wonders for the BArco 800 I sold him years ago, I've never taken the time to change caps that weren't obviously bad. I really should try it one day though, to convince myself one way or the other that they make a difference.. or not.

[Curt Palme]

Well, the set being 18 years old has a lot to do with that as well (Poor convergence issues in the corners/edges)

You can try recapping if you want. Change only 5 or 10 caps at a time and turn the set on to make sure you haven't damaged anything so you can easily retrace your steps.

Kal said it did wonders for the BArco 800 I sold him years ago, I've never taken the time to change caps that weren't obviously bad. I really should try it one day though, to convince myself one way or the other that they make a difference.. or not.

[kal]

Recapping my BG800 made the convergence stable: What took an hour to stabilize when first turned on (and never stabilized to exactly the same spot) changed to 20 minutes and convergenced that always ended up in the spot when the machine as turned on.

I didn't do much for the image quality other than replacing the 6 bipolar caps on the RGB input card (2 on each of the R, G, B lines). That made a big difference to the image quality.

For stability, replace all of the big caps in the SMPS with 105C versions of the same thing. You want want to also replace the larger caps on the horiz and vert deflection boards too, but the large SMPS caps make 90% of the convergence difference. Don't bother replacing the 4 large caps on the AC input module (right before the SMPS). That did nothing for me other than waste my money on large expensive caps.

Your Barco 800 will look best at no higher than 720p for DVD material, assuming you have a 16x9 screen. If you're watching HD material use 1080i. If you're using a Blu-ray or HD DVD player to play back DVDs too, just set it to 1080i and use that for everything (no need to use 720p).

The only way to get it sharper is to upgrade I'm afraid. I went from a Barco 800 to a Cine 8 Onyx and the difference in stability, clarity, sharpness, and low level detail was staggering.

Kal

[kal]

Recapping my BG800 made the convergence stable: What took an hour to stabilize when first turned on (and never stabilized to exactly the same spot) changed to 20 minutes and convergenced that always ended up in the spot when the machine as turned on.

I didn't do much for the image quality other than replacing the 6 bipolar caps on the RGB input card (2 on each of the R, G, B lines). That made a big difference to the image quality.

For stability, replace all of the big caps in the SMPS with 105C versions of the same thing. You want want to also replace the larger caps on the horiz and vert deflection boards too, but the large SMPS caps make 90% of the convergence difference. Don't bother replacing the 4 large caps on the AC input module (right before the SMPS). That did nothing for me other than waste my money on large expensive caps.

Your Barco 800 will look best at no higher than 720p for DVD material, assuming you have a 16x9 screen. If you're watching HD material use 1080i. If you're using a Blu-ray or HD DVD player to play back DVDs too, just set it to 1080i and use that for everything (no need to use 720p).

The only way to get it sharper is to upgrade I'm afraid. I went from a Barco 800 to a Cine 8 Onyx and the difference in stability, clarity, sharpness, and low level detail was staggering.

Kal

[ben12345]

Ok, So I recapped the PSU completely and both the H and V deflection board larger caps. I used Panasonic caps, all with 105' rating.
I did make one small mistake though, I installed C307 on the H deflection board backwards.
After about half a minute of testing, it went pop and my red tube's output went very low. I replaced the capacitor, and installed it correctly this time, but the output is still low.
I pulled the board and swapped in a spare, and all is fine again.
I had a quick peek in the service manual, but cant see how this board effects the intensity of the red tube.
Any ideas?

Cheers,
Ben.

[till]

[Ile]

[kal]

Recapping may make convergence more stable (it did on an older unit I had) but did nothing for sharpness.

Kal

[kal]

Recapping may make convergence more stable (it did on an older unit I had) but did nothing for sharpness.

Kal

[till]

convergence is an issue with my pj as well, so i think will do it

[till]

i just finished my vga - port 3 cable (had the wiring upside down) and ... WOW ... all issues solved, now i see a BIG difference between 1080 and 720 @ 72/75hz, compared to my old vga - switch - port 5 connection. will do the recapping in the next days as convergence is quite annoying (differs between dark and bright scenes etc)

[till]

sorry to bother you again
I want to do recapping in order to increase convergence and image stability but have problems finding the exact components you mentioned, anyone can tell me which caps (ideally the part number) he/she did replace?

an additional issue i observed is that the picture is getting less sharp when the barco is getting warmer (after 60-120 minutes). will recapping help in this case or should i try additional cooling fans?

thanks a lot

[Curt Palme]

That may more be HV regulation issues over convergence. I've never had an issue with the 800 running hot, so I don't think additional fans are required, or will even help.

Try this:

Once the focus gets softer, try tweaking the focus controls on the side of the set, and see if you can dial the focusing back in. Then let the set cool down and see if the focusing is off again when it's cold, and see if adjusting the focus pots again brings it back. If so, then either the EHT board could be drifting or the focus board itself could also be drifting. I've got both parts for cheap if you need them.

[Curt Palme]

That may more be HV regulation issues over convergence. I've never had an issue with the 800 running hot, so I don't think additional fans are required, or will even help.

Try this:

Once the focus gets softer, try tweaking the focus controls on the side of the set, and see if you can dial the focusing back in. Then let the set cool down and see if the focusing is off again when it's cold, and see if adjusting the focus pots again brings it back. If so, then either the EHT board could be drifting or the focus board itself could also be drifting. I've got both parts for cheap if you need them.

[till]

Thanks Curt,
the main issue right now is the convergence drift, so I want to recap the PSU and the deflection boards.
My problem is finding new capactiors, especially c200-c212:




Do I have to take these 4-pin models or will the normal 2 pin caps (with the same specs of course) work as well? Any suggestions?

[Ile]

[till]

thanks a lot Ile, I found a set of 47µF/385V caps (new) on ebay, I think I will get those and take your suggestions for the other caps. In the service manual I can see where the leads are supposed to be soldered, that should not be a problem.

[Ile]

Those high voltage 47uF caps are for 210V line and HTHD, those shouldn't make so big difference for stability. But sure you can swap also those.

+-17V and +-shift lines are mandatory for stability. I swapped all 1000/2200uF caps in my smps.

It's still most critical to swap those few 100uF caps from primary circuit, at other end than output caps inside square sheatsink. Those tend to dry and cause smps to broke. Use 105 degree ones for this (original are 85 degree) and step up for max voltage.

[till]

I did swap the 1000 and 2200µF caps as well as the 100µF caps in the SMPS using Panasonic FC 105°C models. Additionally I did some mechanical adjustments (fasten some screws) and better aiming.
Unfortunately i still have some convergence drifting and have to adjust it every time I want to watch something. Most time the red is drifting, the distance is about the thickness of a line of the internal test pattern. I am thinking about recapping the horizontal and vertical deflection boards as well.

I am not able to use the full phosphor width due to a fixed projector mount, could that be a reason for the drift?

[Ile]

[till]