CurtPalme.com Home Theater Forum

[Gary M.]

I after receiving my BG 1209s/e the other day I got to looking at the video chain cabling and discovered that it is a real mess, I mean a joke actually, way too many PCB connections, soldering splicing and to top it off mini coax that has nothing but a braid shield and solid clear plastic core, I had to do a complete mod on this video coax chain and I did that today, but boy I had no idea what I was getting into

to get to the motherboard which is the center of this mod the chassis had to be completely disassembled, I mean down to a flat bottom, took FOREVER, plus I had to remember where everything goes and every different screw type, anyway I got that out of the way

here is the stock video chain for the Barco 120X:

rear port 5 BNC connectors >
solder >
mini coax >
solder >
mother board >
PCB >
quad board >
solder >
mini coax >
solder >
mini board on RGB board >
mini PCB connector >
RGB board>
PCB >
mother board >
solder >
mini coax >
solder >
motherboard >
solder >
PCB >
mini coax >
solder >
splice to ribbon cable >
mini PCB >
neck card

towards the end there are way too many PCB connectors and the splice at the end to the crappy yellow wire for communication in the 120x is a joke, all this so you have easy connectors to disconnect, although the extra PCB and wiring at the motherboard beneath the neck card is a mystery to me why it is needed

here is my new chain:

rear port 5 BNC connectors >
solder >
mini coax >
solder >
mother board >
PCB >
quad board >
solder >
mini coax >
solder >
mini board on RGB board >
solder
RGB board>
PCB >
mother board >
solder >
mini coax >
solder >
neck card

for mini coax no other than Belden 1522A, the best stuff there is

the mod is rather simple, the time it takes to setup the Belden wire is what takes forever, that mini coax is not fun to work with and strip and get lined out ready to install, basically you install the cable the same way it is on the stock setup

I am going to solder directly to the neck card when I actually get the PJ up and running

I also want to add that it would be easy as pie to remove the port 3 crappy DB9 connector and do another 5 BNC or even VGA whatever, the mini coax chain for it flows as well and is connected right at the back of the port 3 input, I have no use for this so I passed on that

here are the before pics:








modding:











now if I can get this baby up and running this should help somewhat with the PQ, no way it wouldn't

-Gary

[Person99]

[ecrabb]

Bite me, Dave.

Wait, OK. Fine.

To be perfectly honest, I'd bet money that the difference in PQ between the OEM mini-coax as the Barco engineers designed it and Gary's Belden mini-coax mod is very likely impossible to detect looking even at test patterns, let alone watching any program material. Of course, there's no way we could test that supposition, is there? Kind of hard to A-B something that takes hours to switch back and forth.

What is that, a whopping EIGHTEEN INCHES? Scott (TSE) has run high-bandwidth video through something like 100' of junk Radio Shack RG-59 with no noticeable impact to the original 1600x1200/60p signal - I'm pretty sure you're not going to see a difference between adequate factory spec mini-coax and excellent Belden coax.

We're not talking about consumer-grade hardware, here. That Barco was what, a $30-some thousand dollar piece of commercial equipment? The engineering is excellent for the most part. Now, does that mean I think there's anything wrong with doing the mod or that people can't find ways to make improvements? No. If Gary wants to do mods, more power to him! But, merely replacing a run of coax is not the same as Mike Parker completely going over the entire video chain in a projector from top to bottom to eliminate or improve each and every weak point in the chain.

There, are you happy now?

SC

[Gary M.]

I think you missed the point

coax is not the big issue, all the crappy PCB connections are, what about at the end of the chain where the thin signal wire type stuff is spliced before the neck card? you think that makes no difference?

where did I claim this was = to MP mods?, I must have missed that, I also should add this is in prep for getting MP mods I will have to do the 2 video boards again but that was simple

-Gary

[Nashou66]

[kal]

Someone correct me if I'm wrong but didn't Barco redo the RGB video chain connections (and use coax) for the Cine 9/909?

I'm not saying it'll make a difference on all projectors... but just curious.

Kal

[kal]

Someone correct me if I'm wrong but didn't Barco redo the RGB video chain connections (and use coax) for the Cine 9/909?

I'm not saying it'll make a difference on all projectors... but just curious.

Kal

[zGman]

909/Cine9 is about the same in every detail - # of connections, transistions, wire type, etc, etc.
Bandwidth performance on test is better though, due to neckboard improvement mostly, rgb
cards are very similar. 909 has much less blue drop out on bandwidth test, however. Maybe
Gary's work will improve the noise floor - but, as said - hard to AB test. Good to see someone
digging in onto a crt though - I am all for it....better than just talking about this and that...
G

[ecrabb]

[Ile]

Gary, you are right there is lot of connections in signal way and those pcb types are pretty crappy.

Input and driver board connection is terminated to 50 ohm, so original 50 ohm cable (?) could actually work better.

[VideoGrabber]

Gary,

Congrats on a very ambitious project, and thanks for sharing the photos of your journey. At the very least, you won't have any regrets about how you might have been able to make fundamental improvements if only you had taken advantage of the opportunity you had while you had the PJ torn apart for cleaning. Good for you.

[VideoGrabber]

ecrabb,

Your comment was so complicated that I fear you have negated your primary point...
> I do stand by my original contention here - that just swapping... is going to substantially improve PQ. <

I think you left out a "not".

[jkruger]

How many other vultures are out there waiting for a chance at this pile of parts?

[ecrabb]

[Z-Photo]

The first Barco commandment

Get it working

then MOD it.....



Gary - you have beeen fined 1 hour of ampro watching...

signed
commist - the more barco league (aka he man Ampro haters club)

[Gary M.]

yeah yeah I know Pete, but it is simply a quadrupler, no biggie, while I am down, modding, cleaning and retubing a couple I will get the part and slap it in there, all in good time for the big show of testing, finding sweet spot then mounting

oh the joys of CRT, it is killing me to be honest, I just cleaned up on BDs from the Deep Discount sale and they are laughing at me

-Gary

[Gary M.]

[jask]

What is going on with that white connector in Image #11?

[Gary M.]

[jkruger]

Scrolling from the other direction it is in pics 4 and 5. The one with the wires spliced into the backside of it.

[WTS]

Well I'm not surprised to read in the first post that you have no idea what you're looking at when it comes to video cables. Those so called cheap plastic cored cables happen to be very high quality teflon cored video cables. And another thing that you probably missed is the fact that they aren't 75R impedance cables like Ile pointed out, but then again that doesn't surprise me either that you missed that too. You mentioned removing cheap connectors yet you still are using the worst one from what I can see in your pics.

Maybe you should have someone who actually knows what they're doing mod this for you so you don't f**k it up as I'd hate to see a good PJ go up in smoke. Damn, some of those solder jobs look like you used an old wood burning iron to solder with.

I wish you good luck in completing your rebuild project.