Electrohome Marquee 8110 xray radiation, ozon?

S

Skywalkertje

Guest
Hello there everyone!
I am using a Marquee 8110 projector on a sony DVP-999 and Faroudja VP281 processor... the image is very nice.
However I recently opened the projector and there are X-ray warnings on it, saying the device only can be used with shielding in place... I am very worried about this as I sit right behind the projector and shielding is just the case with ventilation holes in it, and some flaps inside that maybe are not in the right spot anymore ! Furthermore the projector often gives horizontal deflection error, which hoes away when I open it up while working, and tap on it, on the rear inside! As I said, I am worried about radiation and ozon issues here too that extent that I would be willing to give up CRT:rolleyes:
Are there any crt's out there without this problem (new ones? Barco cine7,...) I once tried a DLP and hated it for the rain bow effect, ozon and bad, flat image:rolleyes: Help!:lease:
 

Barcoing Mad

Well-known Member
Don't worry - there's plenty of metal between you and the tube faces. If anything, the Quee has more shielding than other PJs I've seen.

+ Ozone will only be generated if something is arcing away.

(Worry about high energy cosmic rays sleeting through your brain every second instead)
 

Swiss-Steve

Active Member
OK,
If you see the warning sticker, then this is a good thing,
As it was placed on the lead based shielding.

Can you take a pic of the sheilding, to show it's location, then I can tell you more about if it is a normal install, or you need to move them.

Ozone, is only an issue if you can hear HV discharge, arching continuously.



On the Horizontal issue,
Take the HDM out,
there is a nylon screw that holds on a small daughter board,
carefully take the board off.
push on the 2 chips in the middle of the board. U525 U528 from memory.
Then put it back onto the main HDM board,
Re-Install into the projector.
Make sure there is a screw into the sleeve and rear heatsink.

Any questions, post back how you went

Cheers
Steve
 
S

Skywalkertje

Guest
To steve: Dear Steve, thanks on the update on both the shielding and the horizontal defelction module!
I will take pictures and will try to solve the module problem as you said... I am curious...I will post as soon as I have photos and now more. Thanks already!:clap:
To all: Manufacturers don't give much information on the radiation issue...
I spoke to a technician earlier this week who told me that radiation occurs once 20.000 Volts are passed... My PJ goes up to 34900 Volts. The radiation however drops logarithmically with distance... so one meter is mininum distance, two meters is reasonable and 3 meters should be safe. Problem is I have to sit right behind it...
Is complete shielding possible? According to the technician even recent crt projectors still use the high voltages and thus have the radiation problem. Is this true?:rolleyes:
regards to all, thx!
 

Swiss-Steve

Active Member
Yes it is true,
But the radiation is only at the outside edge of the tube bell.
This is why the sheild is place over this point.

No need to cover the entire projector in sheilds,
just have all the oem sheilds installed and covers on and you will have no problems.

As mentioned earlier, some projectors don't even have sheilding at all.

My Sony 1020, first CRT, did not have any sheilding, and I had my hands in there all the time as I was learning and modifying.


I really think that you are worrying a little too much about this.
relax and enjoy watching movies

I have attached a pic, this is where the sheild should be



Cheers
Steve

DSC02208.jpg
 
S

Skywalkertje

Guest
Thanks for the picture. I had no time to check on the horizontal deflection module yet, but I did take some pictures of the shielding. It seems to be about where yours are, but the flaps can rotate a bit, as they are only fixed on one point. I showed this on the pictures. there seem to be holes for a screw, but I do not know which one? One flap is a bit bruised as you can see, this is because underneath wires seem to be pushing it against the top plate. I don't think this matters though. I would like your opinion on the rotating flaps and only one fixation point though? This does not seem normal, certainly as there are wholes left open in the flaps, unfixed...
 

Attachments

  • DSCI0005.jpg
    DSCI0005.jpg
    89.7 KB · Views: 114
  • DSCI0007.jpg
    DSCI0007.jpg
    78.2 KB · Views: 144
S

Skywalkertje

Guest
more photos...
 

Attachments

  • DSCI0009.jpg
    DSCI0009.jpg
    86.1 KB · Views: 174
  • DSCI0015.jpg
    DSCI0015.jpg
    86.1 KB · Views: 153

draganm

Active Member
the Marquee projector has the best radiation shielding of any CRT projector ever made. You have nothing to worry about except the fact that your missing the covers over the Focus control Module and Horizontal Deflection. They are important because it's what holds the boards in from sliding out on a ceiling install.
 

Tom.W

Active Member
CRT's are made with lead added to the glass to block X rays. Awhile back over on AVS Art ( A dentist ) placed X ray film in his G-90 for several days and then developed the film and found the film showed no exposure to X rays.
 
S

Skywalkertje

Guest
the Marquee projector has the best radiation shielding of any CRT projector ever made. You have nothing to worry about except the fact that your missing the covers over the Focus control Module and Horizontal Deflection. They are important because it's what holds the boards in from sliding out on a ceiling install.
Thanks for the remark! I do not know what happened to the covers. I got the projector like this from ebay. Do the covers have any other function or are they just to keep things in place? As I don't use the pj upside down, there is no risk. :rolleyes:
 

draganm

Active Member
CRT's are made with lead added to the glass to block X rays. Awhile back over on AVS Art ( A dentist ) placed X ray film in his G-90 for several days and then developed the film and found the film showed no exposure to X rays.
HA, I forgot all about Art's G90's :) The G90 has no additional lead shielding either like the Marquee has. I suspect the extra lead shielding in the Marquee isn't to do so much with X-ray's as it is with suppressing EMI with Radio's and such. This machine was spec'd almost exclusively towards the military and they have strict standards for that.

Thanks for the remark! I do not know what happened to the covers. I got the projector like this from ebay. Do the covers have any other function or are they just to keep things in place? As I don't use the pj upside down, there is no risk. :rolleyes:
no that's all they're supposed to do but living with a CRT on the floor is not fun either. BTW, if you bought this thing off E-bay you really, and I mean REALLY should check the voltage at connector P14. It needs to be at 6.35VDC or you will be burning out the tube filament's. The check is described here, bottom of the page.
ETech :: The Number One Source for Projector Sales, Information, and Technical Tips
If the machine is late 1997 or newer then it's probly OK. IF it's a late 95,1996, or early 97 then there's a real danger to the tubes.
 
S

Skywalkertje

Guest
OK,
On the Horizontal issue,
Take the HDM out,
there is a nylon screw that holds on a small daughter board,
carefully take the board off.
push on the 2 chips in the middle of the board. U525 U528 from memory.

Steve

I managed to get the hdm board out, and located the two chips you are talking about, they are 525 v2.0 and 528 v2.0. I took off the small board is well, as you said. And all I have to do now is just take out the two chips and put them back on? By the way, there is no danger of radiation or other danger, as I am working on the PJ while it is off is there? I had to remove the shielding to get to the screw on the bottom of the HDM board...:rolleyes:
 
S

Skywalkertje

Guest
you really, and I mean REALLY should check the voltage at connector P14. It needs to be at 6.35VDC or you will be burning out the tube filament's. The check is described here, bottom of the page.
ETech :: The Number One Source for Projector Sales, Information, and Technical Tips
If the machine is late 1997 or newer then it's probly OK. IF it's a late 95,1996, or early 97 then there's a real danger to the tubes.

Thanks for the tip, I looked at the link, but the place where they measure is unclear, I am not a qualified technician at all. Any other way I can tell the age of my PJ? On the back there is "property of us government, federal aviation administration N89011", (strange, I got it from ebay germany...). if you want I can give the serial numbers: serial no 097700021, model no 38-p075-AC
:confused:
 

Swiss-Steve

Active Member
Radiation is only produced when the tubes are fired up,
even then, there is no issue,
as you would need to be close to the tube face and outer edges for 6hrs or more to start to become an issue, but you can't get your hands in there.

So from your description, you took out the entire sleeve, if you had to remove the screw way down the bottom.
All you had to do was slide the board out of it's sleeve.

Yes, Very carefully take those 2 chips out of their sockets, then replace them.
Be sure to not bend any legs, or damage the chips when pulling them out.

I use a chip puller,
but you can use a flatblade screwdriver, by lifting one end a small amount, then do the same at the other end of the chip, then back to the other end, etc.

On the cover plate where you plug the projector in, should be a sticker, with the build date, serial number etc.
If not, then press * when next turned on, From memory, it is the first page that tells you software version, Manf.date.

I have attached a pic for the P14 plug position at the bottom, where you need to measure the 6.35v DC
DSC02232.jpg



Cheers
Steve
 
Last edited:

Swiss-Steve

Active Member
This pic will set off a few questions, :rotfl:

But here is a little better pic.
Test where I have soldered on the red wires.

Cheers
Steve

DSC00584.jpg
 
S

Skywalkertje

Guest
Hi steve, I just managed to get out the two chips...
By "replace" them, you mean put them back in (as I had to be so careful not to damage them...) or do you mean I should actually buy new ones? If so, where could I order them?
Apart from the numbers I already mentioned, there is no date... I will have to wait till I get it back running. And I still have to move it back downstairs (see other post):rolleyes:
thx!
 

Swiss-Steve

Active Member
Just put them back in, no need for new ones.

Be sure they go in the same way as they came out,
the notch, or dot should be at one end.


Cheers
Steve
 
S

Skywalkertje

Guest
Pj moved! 1 minute test show it still works!
and no horizontal deflection error...
hope it stays that way... thx Steve!
Before setting it up I want to rent a Geigerteller to test radiation.
When it was on, I noticed a sharp pitch noise, above the fan noise. is this normal? also seems to be a strange smell, not burnt or anything, but strange...
Can something be wrong? Is the high pitch sound normal?
 

Swiss-Steve

Active Member
You may be smelling ozone,
This is generated from a high voltage discharge or high voltage leak.

Oh No,
what did I just say,
now you will be worried about the HV now as well as the radiation :rotfl: :cool:
I think that you are going way overboard with getting a tester, but each to their own :smashin:

I suggest that you unplug the projector,
leave unplugged for about 5 to 10 mins.
Find the HV Splitter block, should be attached to the green tube, the middle one.
Looks like this, see pic below.
DSC02243.jpg


Make sure all 4 cable nuts, the black piece, is tight.(Yes, I have one grey one)
They have a click position to lock them onto the splitter.
Undo one of them and you will feel the lock position.


You could also run the projector with all the lights off, you will soon see a blue arc or leak around the splitter.

Also it could be a leak inside the plastic sleeve at the HV cable on the tube, which you won't be able to see.


Let us know how you go.

BUT First, please do check the 6.35v P14 plug, THIS IS A MUST with a Marquee.


Cheers
Steve
 
Last edited:

Tim in Phoenix

Active Member
The high voltage wires are terminated with Hobson connectors

They are easily tightened with large needlenose pliers, they can engage the indents in the nuts. Careful not to apply excessive torque as you are tightening plastic pieces; also there is a rubber washer in there that you are compressing.


.
 
Last edited:
S

Skywalkertje

Guest
I loosened and tightened the 4 hobson connector. Besides the fans I still here an electronic kinda noise... the smell I mentioned actually seems to come form my Faroudja VP 281 processor... I do not know if this uses high voltage as well?It now sits on the floor, as all connections are not final yet, and the fan of the faroudja is now blowing towards me...
Remains the electronic noise in the marquee...
I checked with * in the marquee 's remote: software version is v3.3, serial nr is 097700021, but there is no manufacture date. with this data, can you tell me if it is still necessary or not to check the pin 14?
 
S

Skywalkertje

Guest
I also had the projector running for 10 mins in a dark room. I did not see any blue light around the voltage divider, tubes were projecting, I could see orange light at the end of them and the other side of course the blue green and red...
 

draganm

Active Member
also seems to be a strange smell, not burnt or anything, but strange... Can something be wrong?
something is definitely wrong. I would wrap the projector immediately in 6 layers of Aluminum foil to keep the radiation inside. I would also do all the doors, windows, and ceiling just to be safe. I hear we're being constantly bombarded by deadly solar radiation. There could also be hidden broadcasts coming through from Alien civilizations trying to pollute our precious bodily fluids. Some people will think you are crazy but all of us here know it's just the right thing to do.:arty:
 
S

Skywalkertje

Guest
BUT First, please do check the 6.35v P14 plug, THIS IS A MUST with a Marquee.


Cheers
Steve
I soldered I 1 m wire to the pin. DC resistance was 2.8 Ohms at the pin and at the end of the wire it was 3.4 Ohms, so the wire and soldering did add a little resistance. DC V was 6.46... I guess this is ok?
I used the pj for about 35 minutes, no horizontal deflection fail, but then the image got faulty: all lines were "zigzag" on the edges; it was not the cabling. I tried switching to standby and back, but same problem. I switched it off completely and back on, and image was good again... I never had this problem before, usually only problem was the horizontal deflection fail, which resulted in no image at all anymore...
Any ideas?
 

The latest video from AVForums

Star Wars Andor, Woman King, more Star Trek 4K, Rings of Power & the latest TV, movies & 4K releases
Subscribe to our YouTube channel

Latest News

HiFi Rose announces all-in-one RS520 audio streamer
  • By Ian Collen
  • Published
What's new on Netflix (UK) for October 2022
  • By Ian Collen
  • Published
Starzplay streaming service rebrands as Lionsgate+
  • By Andy Bassett
  • Published
JVC adds Filmmaker Mode to latest D-ILA projector firmware
  • By Andy Bassett
  • Published

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom