Return to the CurtPalme.com main site CurtPalme.com Home Theater Forum
A forum with a sense of fun and community for Home Theater enthusiasts!
Products for Sale ] [ FAQ: Hooking it all up ] [ CRT Primer/FAQ ] [ Best/Worst CRT Projectors List ] [ Setup Tips & Manuals ] [ Advanced Procedures ] [ Newsletters ]

 
Forum FAQForum FAQ   SearchSearch   MemberlistMemberlist  Photo AlbumsPhoto Albums  RegisterRegister 
 MembershipClub Membership   ProfileProfile   Private MessagesPrivate Messages   Log inLog in 
Blu-ray disc release list and must-have titles. Buy the latest and best Blu-ray titles to show off in your home theater!

BUF 2000 & Marquee 8500 & 1920x1080p & No Sync?

 
Post new topic   Reply to topic   Printer-friendly view    CurtPalme.com Forum Index -> Crescendo-Systems Products
View previous topic :: View next topic  
Author Message
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Thu Feb 12, 2009 2:55 pm    Post subject: BUF 2000 & Marquee 8500 & 1920x1080p & No Sync? Reply with quote


        Register to remove this ad. It's free!
Hi Guys,

I just received my BUF 2000 and was hoping to use it on my HTPC video chain to control gamma. However, the Marquee doesn't seem to want to lock onto a 1920x1080p signal that I'm feeding from the HTPC when the BUF2000 is inserted into the chain - I get scrolling diagonal lines. The Marquee syncs to that resolution fine without it.

Chain:

HTPC Vid Card -> DVI to VGA Adapter -> M-M VGA Cable -> in-BUF200-out -> FF VGA Gender changer -> RGBHV Breakout Cable -> Marquee Input

I haven't tried any other dip switch settings, as I thought the Marquee liked negative sync on H & V?

Any thoughts? I tried a search but couldn't find any threads with similar problems - I'm sure I'm doing something incorrect.

Cheers!

S

_________________
-Scott
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Thu Feb 12, 2009 3:31 pm    Post subject: Reply with quote

Scott,

The are a few possibilities, the Marquee may not like the negative going sync but as you mentioned that is unlikely. The other possibility is that the H-sync is not wide enough. To fix that you have to open the case and turn the small potmeter on the bottom of the PCB clockwise. The best solution since it works without the BUF2000 may be to put it in native (pass-through) H-sync. Again you have to open the case and set SW5 to off and SW8 to on, this will still retain the negative V-sync. The manual that is now available on the http://www.crescendo-systems.com/video_buf.html website explains all the sync options in more detail.


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Fri Feb 13, 2009 12:32 am    Post subject: Reply with quote

beun wrote:
Scott,

The are a few possibilities, the Marquee may not like the negative going sync but as you mentioned that is unlikely. The other possibility is that the H-sync is not wide enough. To fix that you have to open the case and turn the small potmeter on the bottom of the PCB clockwise. The best solution since it works without the BUF2000 may be to put it in native (pass-through) H-sync. Again you have to open the case and set SW5 to off and SW8 to on, this will still retain the negative V-sync. The manual that is now available on the http://www.crescendo-systems.com/video_buf.html website explains all the sync options in more detail.


Kim


Bang-on, Kim. I changed to PassThru Hsync and the Marquee syncs just fine now. Many thanks - time to play with gamma!

_________________
-Scott
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Sun Feb 15, 2009 4:17 pm    Post subject: Reply with quote

Interesting development (By the way, the gamma increase has created just a fantastic picture Kim!! I actually could turn down the Marquee's brightness and contrast quite a few notches.)

If I fire up a calibration tool like Nokia Screen test, and select one of the very detailed focus screens, the Marquee loses sync again and I get a flashing screen, which temporarily syncs but then goes black, continuously cycling until I click away from that test screen.

It only happens on the very detailed focus test screens? I've tried increasing pulse width pot fully clockwise, but this doesn't seem to have any impact on the flashing symptom.

Is it possible that 1920x1080@70hz is too much for the BUF2000's buffer??

S

_________________
-Scott
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Sun Feb 15, 2009 11:16 pm    Post subject: Reply with quote

Scott,

That Nokia Screen test, is that is PC application? From a bandwidth point of view that resolution should not be an issue but there could be something else going on inside. I will see if I can generate something like that and test the BUF2000 some more.


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Sun Feb 15, 2009 11:30 pm    Post subject: Reply with quote

I think I found the Nokia tool, can you point me to the exact screen where it goes wrong? Also does it lose sync even in the H-sync native mode (the width potmeter is not functional in native mode)? What if you do not use the BUF2000, does it work then?


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Mon Feb 16, 2009 6:47 pm    Post subject: Reply with quote

beun wrote:
I think I found the Nokia tool, can you point me to the exact screen where it goes wrong?

Red arrow points at the test screen that won't sync:



beun wrote:
Also does it lose sync even in the H-sync native mode (the width potmeter is not functional in native mode)?

Correct - in H-Sync native it loses sync on the nokia test screen. (I should have realized the pot won't do anything in native mode - thx)

beun wrote:
What if you do not use the BUF2000, does it work then?

I took the BUF2000 out of the chain and I can display the test screen successfully.

_________________
-Scott
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Mon Feb 16, 2009 8:43 pm    Post subject: Reply with quote

Ok,

I will do some serious testing and figure out what is going on, this is weird.


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Mon Feb 16, 2009 9:47 pm    Post subject: Reply with quote

OK thanks Kim.

Interesting - if I open up Windows File Explorer on the big screen, and gradually increase the size of the window by dragging a corner, I'll reach a size that will cause the marquee to lose sync. Once the window fills about 80% of the screen, the image will flash on and off, or roll horizontally.

_________________
-Scott
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Mon Feb 16, 2009 10:40 pm    Post subject: Reply with quote

Scott,

As I remember, the Nokia resolution screen has a large white background and so does the the windows file explorer, I am starting to wonder if that has anything to do with it. If that is the case I will be able to test that relatively easy and find a solution to that problem. I will keep you informed. If you have the case open can you check the values of the two big blue capacitors on the bottom board for me?


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Tue Feb 17, 2009 2:31 am    Post subject: Reply with quote

Scott,

I am still investigating the exact cause but if it is what I think it is, can you change to positive sync or sync on green if the Marquee accepts that? If I am correct that that will temporarily solve your issue. When I have the permanent fix I will send you a new unit.


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Wed Feb 18, 2009 2:13 am    Post subject: Reply with quote

beun wrote:
Scott,

I am still investigating the exact cause but if it is what I think it is, can you change to positive sync or sync on green if the Marquee accepts that? If I am correct that that will temporarily solve your issue. When I have the permanent fix I will send you a new unit.


Kim


Thanks Kim: Here's the results:

1. Capacitor Values: Both are 25v 100uF (85 degrees C)

2. Positive H & V test: You were correct - positive Sync on H&V works fine on all-white fields. All tests in Nokia work fine now.

_________________
-Scott
Back to top
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Wed Feb 18, 2009 2:35 am    Post subject: Reply with quote

I am testing this right now and I am very very sure what the problem is, I will send you a new one when I received some parts. Please PM me with your address.


Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Wed Feb 18, 2009 3:05 am    Post subject: Reply with quote

pm sent. thx!
_________________
-Scott
Back to top
gravymaker



Joined: 01 Dec 2006
Posts: 55
Location: Winnipeg


PostLink    Posted: Sun Mar 08, 2009 7:28 pm    Post subject: Reply with quote

Kim - your fix works great. Thanks again.
_________________
-Scott
Back to top
AnalogRocks
Forum Moderator


Joined: 08 Mar 2006
Posts: 24971
Location: Toronto, Ontario, Canada

TV/Projector: Sony 1252Q, AMPRO 4000G


PostLink    Posted: Sun Mar 08, 2009 8:05 pm    Post subject: Reply with quote

What was the fix Kim?
_________________
Tech support for nothing

CRT.

HD done right!
Back to top
View user's photo album (27 photos)
beun



Joined: 28 Jun 2006
Posts: 676



PostLink    Posted: Sun Mar 08, 2009 11:47 pm    Post subject: Reply with quote

The first few I made had power supply caps that were a bit to small causing ripple on the supply at maximum current draw (peak white and negative going syncs). This ripple is no problem for the video opamps but causes most projectors to see false syncs. I fixed it by sending a new BUF2000 with bigger caps. Choosing sync on green or posive going sync will also fix this issue.

Kim

_________________
ESL-0.5 Full Range Electrostatic Loudspeakers | RTC2200 Component to VGA Converter with Gamma Boost
Back to top
Display posts from previous:   
Post new topic   Reply to topic   Printer-friendly view    CurtPalme.com Forum Index -> Crescendo-Systems Products All times are GMT
Page 1 of 1
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum