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Now the G90 is dead!

post #1 of 68
Thread Starter 
Been having this shaking problem LINK.

I was watching the G90 today and suddenly seem to have lost high voltage. Picture was fine then became blurry, then dimmed out, all in less than 10 seconds. Now I have no raster, no OSD's, and no crackling sound when I start the projector. Also NO ERROR codes. Projector starts and runs fine except no image

I'll start working backwards tonight or tomorrow, but if anyone has any wisdom on loss of high voltage with no error codes I'd be happy to listen.

Also, I just finished John's fan mod to the front fan right before this happened. Seems a little odd, but hey stranger things have happened.

craigr
post #2 of 68
Craig,

I had the same thing happen to me! What I did was pull the front grill off of where the fan resides. The lead I had from SilenX was long enough to leave the fan outside of the card cage so I tucked everything but the fan back in and fired it up again. I quickly noticed that the fan worked intermittently and the shaft was loose. Put the stock fan back in and everything was fine. SilenX sent me a second fan with no problem and it ran fine after that. Hopefully this is the case with yours.

A place to start at least.

Doc
post #3 of 68
After re-reading your post, mine was different. It did shut down. Yours seems to power on but with no HVPS.

Doc
post #4 of 68
Thread Starter 
Quote:
Originally Posted by dochlywd View Post

After re-reading your post, mine was different. It did shut down. Yours seems to power on but with no HVPS.

Doc

Unfortunately yes If the fan stops you actually get an error code and a shut down... my projector just keeps on running thinking that everything is ok.

I'll have some fun with this today (sarcasm). The service manual show the waveform and PP voltage for the high voltage connector. Time to get out the oscope and start there. grrrr

craigr
post #5 of 68
Thread Starter 
All right, I have an update and could use some help form you guys...

I have been trouble shooting the PA board.

Q602 is toast, D608 is toast, and all six fuseable links are blown R614, 615, 616, 617, 618, 619). Q601 is a JFET and is "Sony" part number 2SK2349-CB. I have found them online, but at over $175 each :shock: Page 10-111 of the service manual has the diagram for the transistor and page 8-28 lists the part number. I am not good with JFET transistors (or substitutions in general) so if someone can help me maybe come up with a substitute for the Q602 I would really appreciate a cheaper alternative. PLEASE I HOPE because that's the most freaking expensive transistor I have ever seen.

D608 is part number RD20ESB2. I am having trouble finding info on this diode as well but I think it might be a 2.0 volt, 0.4 watt, zener; can someone confirm this for me. If that's all it is, I'll definitely just get the diode from Digi-Key along with other parts.

craigr
post #6 of 68
Craig,

I'm sorry for your troubles on PA board.

Did you pay attention to the wiring of the PA boards incoming leads/connectors when you re-assembled all the things ? I'm specially thinking about big black HV connectors on the far left/right locations on the PA board. They are named CN89/CN90. Those two female connectors are 875Vpp HV power and must be well secured inside their male on-PA-board parts (you must hear a dual 'click' when they are properly inserted).

For Q602 : This is not a J-FET but rather a Power N-MOSFET for HV DC/DC switching PSU. It is not a Sony part but a Sanyo part. See: http://www.eu.sc-sanyo.com/ProductIn...et/2SK2349.pdf
There should be equivalent part available on the market. Most important parameters are VDSS, VGSS, IDP, PD, VGS(off) and RDS (on) and the pinout should be standard for this package (2131-TO-3JML).

Beware that because Q600/Q601 and Q602 are acting in parallel with same phase, the three parts must share the same transcient specifications (so, same part numbers...)

Ending, if one part has burned, check its relevant PRE-DRIVE stage (Q507/Q508) health !

Hope this helps


John

P.S. FYI, I have three G90 (one is mine) in France that were modded with the SilenX fans that are running for years now without any issue.
post #7 of 68
Thread Starter 
Quote:
Originally Posted by JohnHWman View Post

Did you pay attention to the wiring of the PA boards incoming leads/connectors when you re-assembled all the things ? I'm specially thinking about big black HV connectors on the far left/right locations on the PA board. They are named CN89/CN90. Those two female connectors are 875Vpp HV power and must be well secured inside their male on-PA-board parts (you must hear a dual 'click' when they are properly inserted).

Naturally, they were seated well, of that I am sure.

Quote:


For Q602 : This is not a J-FET but rather a Power N-MOSFET for HV DC/DC switching PSU. It is not a Sony part but a Sanyo part. See: http://www.eu.sc-sanyo.com/ProductIn...et/2SK2349.pdf
There should be equivalent part available on the market. Most important parameters are VDSS, VGSS, IDP, PD, VGS(off) and RDS (on) and the pinout should be standard for this package (2131-TO-3JML).

THANK YOU!

Quote:


Beware that because Q600/Q601 and Q602 are acting in parallel with same phase,

Excellent advice John, I will check them now.

Quote:


P.S. FYI, I have three G90 (one is mine) in France that were modded with the SilenX fans that are running for years now without any issue.

Yeah, I know. But hat being said, the transistor that failed was the furthest from the fan so... I don't know, I think I am going back to stock fans

craigr
post #8 of 68
Thread Starter 
Also John... I think at this point you MUST be the guru of component level repair on the G90's and I am very thankful to have your assistance.

Let's just hope I didn't miss anything while looking over the PA.

craigr
post #9 of 68
http://www.tenfourltd.com/index.php

has the 2SK2349. Yikes! $70 each. 1500V mosfets are not common. 10A parts are pretty unique.

Scott
post #10 of 68
Thread Starter 
Quote:
Originally Posted by tse View Post

http://www.tenfourltd.com/index.php

has the 2SK2349. Yikes! $70 each. 1500V mosfets are not common. 10A parts are pretty unique.

Scott

Sigh...

I decided to just bite the bullet and get it done yesterday and ordered the $175 part. Maybe I'll try and cancel it and get the mosfet from your source.

craigr
post #11 of 68
I believe Ten Four requires you to order a minimum of 5 mosfet's. B&D has them as individuals.

http://www.bdent.com/search/part.jsp?partnum=2SK2349
post #12 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

I believe Ten Four requires you to order a minimum of 5 mosfet's. B&D has them as individuals.

http://www.bdent.com/search/part.jsp?partnum=2SK2349

WOW, great link. They also have some of the other parts I need. Can someone help me with D608? I am having trouble figuring out what it is part number RD20ESB2. I found this, but don't know if it is correct or not:

Quote:
Specsheet from Various
RD20ESB2
General Purpose Reference Regulator Diode

V(Z) Nom.(V) Reference Voltage=19.2
@I(Z) (A) (Test Condition)=5.0m
Tolerance (%)=2.3
Temp.Coef. (pp/10,000) Max.=8
Z(z) Max. (Ohms) Dyn. Imped.=30
P(D) Max.(W) Power Dissipation=400m
Package=DO-34
Military=N

Doesn't seem right to me???

Can someone suggest a substitute diode?

craigr
post #13 of 68
D608 is a RD20ESB2 which is a 19.0v Zener, 1/2 watt and DO-35 case. It crosses to NTE5028A plus others depending on the manufacture.
post #14 of 68
Just to clarify how to determine this manufactor, if it was RD2.0esb2 it would be a 2.0v. If it was RD6.5esb2 it would be a 6.5v. Since the G90 manual lists it as RD20ESB2, its actually a 20v however NTE cross reference lists its cross as a 19v.
post #15 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

Just to clarify how to determine this manufactor, if it was RD2.0esb2 it would be a 2.0v. If it was RD6.5esb2 it would be a 6.5v. Since the G90 manual lists it as RD20ESB2, its actually a 20v however NTE cross reference lists its cross as a 19v.

Yeah, that kept tripping me up

craigr
post #16 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

D608 is a RD20ESB2 which is a 19.0v Zener, 1/2 watt and DO-35 case. It crosses to NTE5028A plus others depending on the manufacture.

I'm trying to find a cross ref at B&D so that I can just get all the parts from one place. Any suggestions? I found this one (LINK)

craigr
post #17 of 68
The RD22EB1 is actually a 22v and I would not recommend it. Here is a data sheet on the RD series diodes:

http://pdf1.alldatasheet.com/datashe...C/RD22EB1.html

As you can see the specs for the sony replacement gives a voltage range for the B2 of 18.73 to 19.57 volts. I skimmed over B&D's zener list and the closest I saw was GZB20.0B. See attached:

http://www.bdent.com/search/part.jsp?partnum=GZB20.0B

Its 20.0v and 1 watt. You can increase the wattage, but you should not change the voltage. Voltage is critical. Wattage just allows it to carry more current. To bad B&D didn't have a better selection of Zener's but this is common with suppliers that carry uncommon parts to other suppliers. Good luck.
post #18 of 68
Thread Starter 
B&D also has this one 18 volt (LINK).

From the datasheet (LINK) it looks like the RD18EB3 is 17.51~18.30 volts and the RD22EB1 is 20.23~21.08 volts. Those seem to be the closest two that B&D has. So should I go with a slightly lower voltage, slightly higher voltage, or just order the NET part which seems to be a slightly higher voltage than stock, but less so than the RD22EB1?

Advice?

I already canceled my order from the ridiculously high priced place. They were easy having all the Sony part numbers, but at over $300 for all my parts with 2nd day air they are too high. The only thing that B&D doesn't have is Q507 and Q508, but they seem to be ok. I was going to just replace them to be sure, but I think I will try my luck.

craigr
post #19 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

The RD22EB1 is actually a 22v and I would not recommend it. Here is a data sheet on the RD series diodes:

http://pdf1.alldatasheet.com/datashe...C/RD22EB1.html

As you can see the specs for the sony replacement gives a voltage range for the B2 of 18.73 to 19.57 volts. I skimmed over B&D's zener list and the closest I saw was GZB20.0B. See attached:

http://www.bdent.com/search/part.jsp?partnum=GZB20.0B

Its 20.0v and 1 watt. You can increase the wattage, but you should not change the voltage. Voltage is critical. Wattage just allows it to carry more current. To bad B&D didn't have a better selection of Zener's but this is common with suppliers that carry uncommon parts to other suppliers. Good luck.

Well that one looks pretty good...

craigr
post #20 of 68
Thread Starter 
I ordered six of the GZB20.0B and figure I will replace all of them with the same value rather than having five oem parts and one sub.

$91 for all parts with 2nd day delivery sure is better than $300 and change.

Thanks for your help!

If anyone else wants to chime in on the diodes, please do and I will order more exact ones from another vendor if you guys think it is prudent.

craigr
post #21 of 68
I agree with changing all of them. Whats sucks is not knowing just what caused the problem and if you replace all these parts and it takes them out again. I dont know if your looking for more suggestions but I'll throw some out there anyways. First did you check the other mosfets? Q600,Q601 and Q602.I would also recommend checking diodes D609 and D610. I would also check caps C600,C601, C602, C603,C607, C608, C610 and C611 for shorts to gnd. Then I would disconnect CN89 and CN90 to the flyback and check my 200v at TP600 on the PA board. Then if it was me I would replace the parts but leave the flyback disconnected and run if for awhile to make sure the circuit holds, without blowing again. If it does I would then shut it down and reconnect the flyback with CN89 and CN90 and see how it does. If it then blows, you at least have an idea what is causing it.
post #22 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

I agree with changing all of them. Whats sucks is not knowing just what caused the problem and if you replace all these parts and it takes them out again. I dont know if your looking for more suggestions but I'll throw some out there anyways. First did you check the other mosfets? Q600,Q601 and Q602.I would also recommend checking diodes D609 and D610. I would also check caps C600,C601, C602, C603,C607, C608, C610 and C611 for shorts to gnd. Then I would disconnect CN89 and CN90 to the flyback and check my 200v at TP600 on the PA board. Then if it was me I would replace the parts but leave the flyback disconnected and run if for awhile to make sure the circuit holds, without blowing again. If it does I would then shut it down and reconnect the flyback with CN89 and CN90 and see how it does. If it then blows, you at least have an idea what is causing it.

I always welcome suggestions!

Quote:


First did you check the other mosfets? Q600,Q601 and Q602.

Checked them all.

Quote:


would also recommend checking diodes D609 and D610.

Already done.

Quote:


I would also check caps C600,C601, C602, C603,C607, C608, C610 and C611 for shorts to gnd.

Couldn't hurt, but they are not bulged or anything weird.

Quote:


Then I would disconnect CN89 and CN90 to the flyback and check my 200v at TP600 on the PA board.

I checked this before I even removed the board and had a working 200 volts.

Quote:


Then if it was me I would replace the parts but leave the flyback disconnected and run if for awhile to make sure the circuit holds, without blowing again. If it does I would then shut it down and reconnect the flyback with CN89 and CN90 and see how it does. If it then blows, you at least have an idea what is causing it.

Probably wouldn't hurt

Thanks
craigr
post #23 of 68
Thread Starter 
Quote:
Originally Posted by macgyver655 View Post

I agree with changing all of them. Whats sucks is not knowing just what caused the problem and if you replace all these parts and it takes them out again.

Yeah, and I heard that! However, even though John has had good luck with the fan mod, I really think this was caused by over heating. I had just changed the fan 25 minutes or less before this happened. The chassis only has around 700 hours on it. And when I pulled the PA 15 minutes after the high voltage failure the heat sink was still too hot to touch... literally.

craigr
post #24 of 68
Quote:
Originally Posted by CIR-Engineering View Post

I had just changed the fan 25 minutes or less before this happened (...) And when I pulled the PA 15 minutes after the high voltage failure the heat sink was still too hot to touch... literally.

You must had something wrong with the fan then ! Did you checked that he was running fine ? I sometime found that G90 did not sense its blade rotation correctly (and then allow the G90 to run without front fan in operation ).

John
post #25 of 68
Thread Starter 
Quote:
Originally Posted by JohnHWman View Post

You must had something wrong with the fan then ! Did you checked that he was running fine ? I sometime found that G90 did not sense its blade rotation correctly (and then allow the G90 to run without front fan in operation ).

John

Funny John, I couldn't sleep last night and was thinking about just that. I bet the new fan got pinched or something when I put the front cover back on and stopped spinning. I to have noticed that on occasion the G90 has failed to sense a stopped fan. I am thinking my new fan was not running...

criagr
post #26 of 68
Cant you just put the original front fan back in to check if that clears the fault Craig, Some leave the front OEM fan in but change the other's because of the lack of air flow over the PA board after doing the front fan mod....
post #27 of 68
Quote:
Originally Posted by CIR-Engineering View Post

Funny John, I couldn't sleep last night and was thinking about just that. I bet the new fan got pinched or something when I put the front cover back on and stopped spinning. I to have noticed that on occasion the G90 has failed to sense a stopped fan. I am thinking my new fan was not running...

Yes, that's the point In fact, depending how the ABS front cover cutout has been done, if it's too tight then the fan can be mechanically pressed and stops spinning. I always checked the fan blade rotation when cuted the plastic and placed back in place on the PJ.
Since that the G90 spin detection hardware is sometime lacking of the SilenX mis-rotation signal detection, this could let the unit running while the blade is stopped

I really think that this was the real cause of your PA board burn
I must amend my DIY post in here (and in Curt Palme forum) to warn people about this

John
post #28 of 68
Quote:
Originally Posted by cinema mad View Post

Some leave the front OEM fan in but change the other's because of the lack of air flow over the PA board after doing the front fan mod....

You can also do the SilenX mod in front of the PA board and leave the original 60mm stock Sony fan running at a lower speed (put a resistor in serial with +12V line). Then, you'll have two fans running at low speed and more aiflow over PA/PD board heatsinks.

John
post #29 of 68
Thread Starter 
I'm thinking about doing your first G90 fan mod now John... the one with the SilenX fan in the original location.

craigr
post #30 of 68
It works Craig,

I've been using it for 6 month or so (before I use the front larger fan solution). The only issue is the noise that is quite worst than the current solution (60mm fan running at full speed is always making more high pitched noise than larger fan because of the higher spinning speed between 3000 and 4500rpm).

John
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