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Discussion Starter · #1 ·
I thought I had this problem with my Sony 1031Q under control, but I definitely do not! So far I've made 5 adapter cables thinking that my soldering job is the issue, and every time I get the same results...major ghosting. The last adapter was only 3 inches long and I removed the solid core Cat 5 wires from their outer casing to make them easier to work with.


I got a very high quality a 25 foot extender cable that is running from the PC to the PJ, and I'm sure that cable is not the problem because I hooked it up to my computer monitor which is running at a very high resolution and there is NO ghosting whatsoever. So it's either my custom made adapter or a problem with the PJ. The projector works great otherwise and the picture is beautiful, I just need to get this nasty ghosting issue cleared up.


What am I doing wrong :confused:


Why did Sony use such an oddball VGA connector on the 1031Q anyway? Getting it to work properly is going to drive me to drink ;)


Larry
 

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Discussion Starter · #2 ·
One more question. With such a short adapter does the type of wire I'm using make a difference? I used solid core shielded Cat5 each time.


Larry
 

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Larry-


You did converge the unit, right? :) (Just kidding!)


As your adapter is so short I doubt it is the problem.


I would guess that your computer and monitor are on the same circuit, but something tells me your PJ is plugged in somewhere else...? If so, just for grins you might try plugging the PJ and computer into the same outlet.


Just a guess- hope it helps.


--Kieth
 

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Discussion Starter · #4 ·
Keith - It already is plugged into the same circuit as my PC.


Also, it's not my solder job! I just did an experiment where I replaced the DB25 end of my adapter with a female HD15. I then plugged this in between my computer monitor and my 25 foot extender thats plugged into my PC. No ghosting at all on my PC monitor running at a very high resolution and the adapter right in the middle of the circuit!


The problem must be in the projector, which would explain why I had the same ghosting issue when I hooked the PJ up to my DVD player via the video input.


So what should I do now?? I'm stumped!


Larry
 

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Can you show us a picture of the problem? If you have this issue using the video input, it's gotta be a projector issue.


Vern
 

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Discussion Starter · #6 ·
Quote:
Originally posted by Vern Dias
Can you show us a picture of the problem? If you have this issue using the video input, it's gotta be a projector issue.


Vern
I've attached a picture for you.


One other little tidbit...The level of ghosting seems to vary. Some times it only 2 deep sometime 5 or 6. And it doesn't seem to necessarily coincide with how long the PJ has been running.


Larry
 

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Cheap experiment. Go to a hardware store and pick up one of those ground adapter plugs. You know, those things you use with a grounded plug (3 leg) when you dont have a grounded outlet to plug into. That picture looks like a ground loop problem, but I could be wrong. Also check that the outlet is wired correctly. With the wall trim removed look in with a flashlight. The connections on the receptical are color coded. The neutral wire (white) should be connected to the chrome colored screws and the hot wire (black) should be connected to the brass colored screws. Don't stick your fingers or anything else in there or you will have a bad day.

Hope this helps?


Chip S.
 

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The projector does have the 75 ohm termination on the RGB lines enabled, correct?


What resolution are you running at?


Vern
 

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Discussion Starter · #9 ·
Quote:
Originally posted by Vern Dias
The projector does have the 75 ohm termination on the RGB lines enabled, correct?
Uh...how do you do that on a 1031Q:confused:


Larry
 

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No clue, as I am not familiar with that projector. But is does look like some sort of termination problem that is causing reflections on the signal lines. Are you sure that using S-Video shows the same effect?


Vern Dias
 

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Discussion Starter · #11 ·
The PJ doesn't have an S-Video connection. But I did see ghosting when I had it hooked up to the composite input.


Larry
 

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Did it look identical to the photo above?


Another thought, does the projector have an aperture adjustment?

If so, it could be set too high. (May also be called sharpness)

Vern
 

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Another thought, On your custom made adapter, you are carrying the ground leads for R, G, and B through independently, correct? And you have verified that each ground wire is connected to the correct pins on both ends of the jumper cable? In other words don't mix the R shield with the G shield with the B shield. BTW, you probably need to use 75 ohm shielded cable for your adapter, no matter how short, since the discontinuity in the 75 ohm impedance is what causes the reflections which cause the ghosts.


Vern
 

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Discussion Starter · #14 ·
Vern, yes the ghosting through the composite looks pretty much the same, you don't notice it as much because it gets somewhat lost amidst the icky scan lines and interlacing artifacts that you get with composite.


As for the cable, I've check and rechecked numerous times and they are wired according to the spec I was provided by another forum member.


You are probably right about the ghosting being caused by reflections from improper termination, but I doubt it is from the adapter. Other forum members have made adapters for the 1031 from Cat5 cable and do not suffer from ghosting - and mine is so short that it seems unlikely they would interfere with impedance, but I could be wrong. Also the fact that I get the same ghosting from the composite input leads me to believe it's something to do with the PJ. I will try to dig up some 75 ohm coax so I can make the adapter according to spec just to be sure.


Larry
 

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Could you post that spec?


Your pairs should be:


1 & 6

2 & 7

3 & 8


5 chassis ground


13 H Sync

14 V Sync


10 Sync Return


with 1,2,3 being the hot and 6,7,8 being the return (coax shield)


Vern
 

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Discussion Starter · #16 ·
The spec for the VGA adapter is:


HD15 -> DB25

----------------------------

1 -> 6 // Red

2 -> 5 // Green

3 -> 4 // Blue

6 -> 15 // Red Ground

7 -> 16 // Green Ground

8 -> 17 // Blue Ground

13 -> 3 // Hor Sync

14 -> 3 // Ver Sync


Note: the 1031Q requires a composite sync. There is no sync return.
 

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Discussion Starter · #17 ·
Does it matter if the coax is RG58A? I realize it's 53 ohm, but the only RG59 I have found so far is heavy duty stuff used for cable TV etc.


Also, do I need to use coax for the sync signal as well?


Larry
 

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I second your thought on the 25 pin RGB2 port. RGBS connectors would have been SO nice to have. Then again I bet it could be done with some modifications. Take out the internal video decoder and CCQ port to make room!


So are you using a computer interface with your 1030Q? If so I heard that you should terminate the 15 pin VGA connector. I don't terminate mine and I get a slight vertically moving horizontal noise, but I don't get ghosting.
 

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Discussion Starter · #19 ·
Another tidbit I just discovered...The ghosting also shows up on the PJs internal test pattern. The PJ only has a couple of test patterns, one of which is a solid white block, and the ghosting is readily visible on that pattern. That pretty much proves the problem is internal.


I have a call into Hammerhead tech (where I bought the PJ) and they are going to work with me to try to solve this problem. It's either a configuration issue or a defective component - not sure which yet.


Larry
 

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Quote:
Does it matter if the coax is RG58A? I realize it's 53 ohm, but the only RG59 I have found so far is heavy duty stuff used for cable TV etc.
You should really be using RG-6 rated at 75ohms to insure the best possible signal transmission. I realize that your Sony 1030Q only has a 25 pin RGB input, but I would still run RG-6 (or equivilant) 75 ohm rated cabling to your projector and then have a custom 25 pin termination made for the projector's input.


You are correct that their is likely something wrong with the projector if you are experiencing "ghosting" even with the internal test patterns. Hopefully Hammerhead will take care of the situation.
 
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