CurtPalme.com Home Theater Forum

haireez · Last edited by haireez on Thu Dec 20, 2012 10:47 am; edited 1 time in total

Hi,

Need some trouble shooting advise from you guys.

I have 3 HVPS. One good & 2 bad HVPS.
Unable to fire up blue tube but green & red tube fire up nicely. After i've changed with another Hvps, everything works fine.

On another bad HVPS, , all 3 tubes becomes blurred after I switch 'ON' for more than 30 mins. It will remain blur for about 2 minutes & will be sharp again for a few minutes. This cycle would repeat again & again.

Please advise on what could be the probable root cause so that I could start troubleshooting both HVPS.

Any feedback will be greatly appreciated.

macgyver655 · Joined: 22 Aug 2007 Posts: 8508

The one with no blue is probably no G2 on the blue line. Can you swap the G2's between blue and green or red and verify the problem follows.

Tough call on the other one. I'll look over some prints.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

As mAc said the First HV has no G2 for the Blue.

Now have you tried cleaning the contacts on the vertical daughter board of he one that goes in and out of focus?

I had one do that, I did the resistor mods and must have not pushed the daughter card all the way in. I reseated it and all was better. Hope yours is that simple.

Athanasios

haireez · Posted: Tue Dec 18, 2012 3:21 pm Post subject:

Hi Nashou,

I did clean the daughter board and try reseating it. Unfortunately, it became out of focus again after you run the projector for an hour. After 5 minutes, the focus is back to normal. Its just an intermittent out of focus.

As for the first hvps, im not too sure how you swapped G2. Please advise how to swapped G2 connector.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

you have to do it with the G2 connector on the Video Neck Board. So remove the G2 connector that goes to the VNB of the green ann connect it to the Blue G2 connector on the VNB. its the black wire with the appropriate color end for the tube it goes to.

Athanasios

haireez · Posted: Wed Dec 19, 2012 12:35 pm Post subject:

Hi Nashou,

I tried to swapped between green & blue G2 connectors but found out that the green G2 connector unable to reach blue tube. Before I do any testing, can I just connect blue G2 connector to green tube and just let the green G2 connector detached as is? Will it cause any damage if I did not connect the green G2 connector to blue tube?

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Yes you can try that with no issues.

Athanasios

haireez · Posted: Wed Dec 19, 2012 2:44 pm Post subject:

Hi Nashou,

Macgyver is right. I connected the blue G2 connector to the green tube and now the green tube did not fire up too.

How can I repair my HVPS blue G2? I hope someone in this forum could guide and tell me which component is faulty so that I could change the reverify again.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

I never repaired a HVPS since I never had one fail. But Mac might be able to help. But look at the blue channels resistors for failure. the film caps are harder to notice and you'd need a LCR meter to measure them. Could be one of the Mosfet's.

I dont have the Schematic here at work

I'll let Mac chime in.

Athanasios

barclay66 · Posted: Wed Dec 19, 2012 3:29 pm Post subject:

Hi,

If only the blue G2 line is dead I would first check the resistors R21, R22 and R23. I've put a red circle around them in the picture and in the schematics...

Regards,
barclay66

P.S.: Check out this thread for more information on the resistors and recommended replacements (it's already explained on the first page of this very long thread).
https://www.curtpalme.com/forum_archived/viewtopic.php@t=9608.html

haireez · Posted: Wed Dec 19, 2012 3:29 pm Post subject:

Thanks Nashou for helping me on this. By the way, the P/N is X2532 rev.B4. Hopefully, Mac able to tell me the specific part thst need to be change.

haireez · Posted: Wed Dec 19, 2012 4:26 pm Post subject:

Hi Barclay,

You're the guy! At first I tried changing r23 only but the blue tube still doesn't fire until I changed r21 & 22 and now the blue tube fire up!!!! Thank you!!!

By the way, do you know how to solve the other HVPS that is having intermittent focus issue?

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hello

Try swapping the little upright circuit board, could be something unstable on that.

.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

hiareez, make sure the new resistors are at least 1 watt and not wire wound. That gives of magnetic field. Ceramic or Carbon Film, and even a high quality metal Film that are rated up to at least 700 volts, 1000 volts is even better.

Athanasios

haireez · Posted: Thu Dec 20, 2012 4:08 pm Post subject:

Hi Tim,

I tried to swapped HVPS daughterboard but still no improvement.

haireez · Posted: Thu Dec 20, 2012 4:09 pm Post subject:

Hi Nashou,

I have attached photo of new resistor.

haireez · Posted: Fri May 09, 2014 2:51 pm Post subject:

Hi,

Need some advice again but this time round my red tube did not fire up. I've replaced R9, R10 & R11 but still red tube fid not fire up.

Appreciate any advice from everyone here. By the way, i have an tested with my unstable hvps and got all tube fire up. Definitely problem with the first hvps.

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hello

See if G2 is reaching the neckboard at tip of R76

Try measuring filament voltage at motherboard connector P14, near the back of the blue tube. Should not exceed 6.50 vdc

Try swapping neckboards

haireez · Posted: Fri May 09, 2014 3:21 pm Post subject:

Hi Tim,

I'm not too sure what you mean by " See if G2 is reaching the neckboard at tip of R76 mean". Can you please explain a little bit more on this.

Secondly, to check the P14 value, do you mean that i need to 'OFF' the projector or 'ON'?

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Hello

Connect a voltmeter and look for ~500 volts dc at tip of neckboard resistor R76 relative to chassis ground

Look for safe filament voltage across the two pins of P14 around 6.35 volts dc. with power ON. Higher filament voltage will ruin the electron guns