We keep seeing posts about projectors with high hours in STAND BY but low running hours.

I keep seeing CURT respond saying that the CRT's will not focus as good even though they havent been used because they get weaker in standby mode.

Heres my qurestion...

Like my BARCO 701s it had a MAINS power switch that put the main power on and off. The remote on the other hand would turn the PJ on and off. In the off position with main power on that is concidered to be STAND BY. HOWEVER the CRT's are off as well as most of the other internal parts. The Heater filement is not glowing in the rear of the CRT at all. So in this state is this what will cause the tube to get weak? I doubt it I think Im missing something?

Ok I now have a DWIN HD700. There is no mains power switch. The power comes on to STAND BY when the power cord is plugged in. The CRT heater is not glowing when the PJ is off, just the little green power light blinking to state its in STAND BY.

I dont see how the tubes are being wore out at all like this.

What I have read on here has made me think that some projectors are left on in VIDEO MUTE mode. ( fully on tubes on w/ heater glowing ) just with no video signal applied. I can see this aging the tubes and putting ware on them for no reason and the unit aquiring countless hours. Sure NO burn in will exist but I can see how its killing the tubes as they are essentially on.

Is that what some of these posts I have read are refering to or am I really not getting it?

On a side note you cant run a DWIN in video mute mode as the green tube will display NO VIDEO SIGNAL and it scans arund the screen to prevent burn in. However you know as well as I do that if any one was to leave that going on for a wile it will eventually burn in in many differant places.

Im posting this as its something I have read in the past more then one time and never really gave much thought to it and as of now think that is been miss represented due to what I have poseted above. Maby the wrong terminology has been used in the past and its got me thinking about it.

Vic,

On the Marquee line of projectors, when they are plugged in and in the standby mode (ie not on) there is a voltage (I think around 4V) that is applied to the filiments. This voltage, even though it is lower than the operational 6.35V, wull cause emissions to get lower after long periods of the PJ in standby mode.
This is why you will see Marquee owners and buyers saying their tubes look pristine white with no wear but they don't have any light output.
I am only aware of the Marquee series using this scheme in standby as no other projectors I am aware of do this. I always suggest that Marquee owners unplug thir projectors when not in use.

Terry

Terry - standby mode means you've put the marquee into standby, not that it is just connected to power isn't it? what is wrong with just keeping it plugged in and turned off?

I understand what Terry is saying, but don't know that I agree. In Marquees only, the set in standby/off mode (as long as it's plugged in) applies about 4 volts to the filament. This is to make a faster turnon, so that the filaments are always partially lit on the tubes. It's like a preheat condition in theatrical lights, there's always a few volts on the bulbs so that they turn on instantly instead of ramping up from 0 volts. It's also less hard on the filaments as they are always warm.

Anyways, my point of contention with Terry's post is that I too have seen dead tubes with pristine phosphors out of high hour machines. This indicates a tube that has had little 'on', or 'lit phosphor' time, but long hours of the tube being on.

Correct me if I'm wrong, but neither hour counter advances in a Marquee when the set is off or in standby mode, right? Therefore, in order for either counter to advance, the set must be turned on.

If the above is correct, then I must say that I have never seen a dead tube with low standby and low CRT tube count. In other words, all dead tubes came out of sets that had say >20,000 hours of time where the projector was turned on fully.

If what Terry says above is true, then assuming that a set was plugged in 24/7 since installation, almost every set that had more than 4-5 years of being plugged in would have dead tubes in it.

So I don't know if the off/standby voltage of 4.0 volts contributes any to tube emission failures. I've had a number of dead emission tubes in Barcos as well. Don't know if I've ever had any 30K hour+ NEC sets in, as the hour counter resets to 0 when it hits 9999. I don't think I've ever had a dead emission NEC tube, oh except for the old DP-1200s.

BTW, my own 9500LC with used tubes has now been installed in my own HT for about a year now, with 8000 hours+ of off/standby time and maybe 200 hours of actual 'on' time. No change in emissions or G2 settings.

Yeah, I thought the "standby" issue with Marquees was when you hit the STANDBY button. The projector is still **on** and is still fully heating the filaments, so naturally it would eventually wear out the emissions. I'm sure there were plenty of industrial installations where the projector was remote or enclosed and the users just didn't realize it was still on when they hit STANDBY.

If the "turned off" mode actually wears the filaments, then we all need to make sure we pull the power from our Marquees when we're not watching them. But I'm with Curt -- if that was the case, almost every Marquee that's more than 3-4 yrs old (assuming it was plugged in that whole time) would have dead tubes.

On the other hand, why else does it run the LVPS fans when it's "off" ?? Never made sense to me...

Not sure, but I do know that I left one fan unplugged in a LV supply once... and it caused all sorts of convergence drift. Took a while for me to figure out what the heck I did..:)

Well thanks to all the posts relevant to Marquee's and standby issues , I've been proactive with my theatre build and incorporated a wall switch into the pj's ceiling socket power supply lead. :cool:

Once I have finished watching whatever source , all I will do is power down and then throw the wall switch after a 10 min cool down.

Maybe guys can use this idea. No need to break out a ladder or stool to get to the socket on the ceiling. Works for me. :)

Mark

I think maybe though when you reconnect the power, make sure it's left that way for a little before trying to switch the projector on. I arced my HDM I think by having the set unplugged for a few weeks, then reconnecting it and powering the projector on almost immediately.

Yes this is exactly what I thought the case was then and have been understanding what I have been reading all along......

So the only thing I can assume is since I dont see the filiments lit in the DWIN that when the Pj is Off ( with power still hot ) that the tubes are actually off. Since there is no heat generated at all in this position I think Im safe.

Its funny the E homes keep the tubes warm in stand by becuase the DWIN starts up really fast and warm up time is very very short compaired to what I had to wait on the onld SONY 1031q and BARCO 701. The DWIN warms up problably within 5 to 8 minutes where the SONY and BARCO's I had needed at least 30 mins to fully converge and throw a nice sharp picture. The dwin is completly watch able as soon as the image is projected. The only thing thats a little out of sorts is like the text from my on screen Sat Guide, its a little fuzzy but with in a few minutes is DILA sharp!

But then again the E Home is using bigger tubes too so maby thats why they run them all the time.

The DWIN warms up problably within 5 to 8 minutes where the SONY and BARCO's I had needed at least 30 mins to fully converge and throw a nice sharp picture. The dwin is completly watch able as soon as the image is projected. The only thing thats a little out of sorts is like the text from my on screen Sat Guide, its a little fuzzy but with in a few minutes is DILA sharp!

Your Sony's and Barco's had bad caps or other issues then. My Barco has its convergence perfectly in about 4 seconds after I turn it on. The picture will get progressively sharper for about 15 minutes, but this is subtle and my wife can't tell the difference in the picture from just turned on and running for an hour.

BTW, somewhat incorrectly, but easy to grasp, I explain the Marquee "problem" by basically saying, standby to a quee is video mute to all the other projectors. :)

Dave

@crt nuts..... isn't this a risky approach. If that switch is thrown while the set is powered up, would you not experience spot burn?

I unplug my unit when not used. To many horror stories of lightning hits on the hydro lines destroying expensive equipment.

No, it shouldn't spot burn, but he did say power down first.

I do the same thing. Turn off the powerpoint after turning off projector - it also turns off my extraction fans.

I understand what Terry is saying, but don't know that I agree. In Marquees only, the set in standby/off mode (as long as it's plugged in) applies about 4 volts to the filament. This is to make a faster turnon, so that the filaments are always partially lit on the tubes. It's like a preheat condition in theatrical lights, there's always a few volts on the bulbs so that they turn on instantly instead of ramping up from 0 volts. It's also less hard on the filaments as they are always warm.

Curt,

This is the part of the EHome methodology I really don't understand. The Marquees DON'T turn on any faster than any other CRT I have ever seen from this standby state (ie with filaments "warmed") therefore I have never understood why they do it??
Now if it's an issue of putting less stress on the CRT......maybe, but I would think that we would be seeing the effects of this stressing on other CRT's that don't use this?

As I understand it, the standby counter is running as long as the Marquee is plugged in?? no??

Terry

Good questions Terry!

Maybe the color balance is more stable from turnon to an hour later?

I'll have to see if the sets run either counter when just plugged in. I'll try that Saturday night and will post again.

Curt,

As I understand it, the standby counter is running as long as the Marquee is plugged in?? no??

Terry

No, that's not right.

This is just simple semantics confusion. The STANDBY mode on the MArquee is akin to a 'pause' or picture mute mode. When you hit the STBY button on the remote it just mutes the picture but the machine is completely fully turned on. The chassis meter runs here, but not the tube hours. When you take it out of standby both meters run. When you turn OFF the machine with the POWER button but leave it plugged in, there is still fan running and the filaments are on a little bit, but no hour meters are running.

Note how different this is than the Barcos, where the STANDBY button turns the machine on and off, but the Pic Mute button mutes the image.

When a barco is in Standby, it is OFF.
When a Marquee is in Standby, it is FULLY ON but muted image (no picture).

This is because Marquee label the on/off button "POWER" and Barco labels their on/off button "STANDBY."

Obviously this leads to these confusions because people just talk past each other using the term "standby" when talking about different machines.

@crt nuts..... isn't this a risky approach. If that switch is thrown while the set is powered up, would you not experience spot burn?

I unplug my unit when not used. To many horror stories of lightning hits on the hydro lines destroying expensive equipment.

In answer to your question Soupsuds....No... I've placed the switch behind the component racks completely isolated from any other switches just for that reason.
Imagine asking your 8 yr old turn off the lights and the wrong switch is thrown....actually let me retract that. Lets not imagine that... awefull consequences I would think :mad:
Thats an important point though, the lightning. I have made provision for easy access to the power supply lead incase of future changes.

I think maybe though when you reconnect the power, make sure it's left that way for a little before trying to switch the projector on. I arced my HDM I think by having the set unplugged for a few weeks, then reconnecting it and powering the projector on almost immediately.

Yes Gino..agreed albeit unconsciously. I always first do some hoeing and hahing before I eventually hit the power button on the remote. Its always a question of , what movie do I feel like watching or making popcorn first or waiting for the rest of the family.

There is always that inevitable delay for some reason or another and I guess I will no longer complain about this (built in safety factor) delay.

I always count to twenty after turning on the powerpoint, before I turn the projector on.


And you shouldn't get spotburn when the power goes hard out. Not a nice thing to do, but it shouldn't get spotburn. I tripped the safety switch messing with a broken Xtra powersupply while my wife was watching the Xtra - it was fine.

Re Spot burn, I thought scanning systems pushed the beam off screen on shut down but it relied on some current discharging via the yoke.
I remember un-pluging a regular TV and watching the beam hit dead centre and gradually fad away. Maybe it's different...
OK now, everyone, pull that plug, 3,2,1.......

Person99

Yea, I understand your explanation, that is exactly what I figured...

Its possible my SONY had problems, it took about 30 mins for it to look perfect. The BARCO, who knows it was a BARCO fixed and fixed again...as you know I what I wanted to to do to it lol......But the DWIN MMM MMM MMM its by far the best projector I have ever owned....

Just upgraded my preamp last night to one that has component video switching and now runing all component video scaled to 720p. Tthats squeezed even more PQ from my DWIN.... I was previously running all S video scaled to 720p and had an amasing picture now its at the next level.....


GARYFRITZ.........Um what can I say..... RAZZZZZER SHARP to the 100th power @720p :)

Vic