20 Most Recent Hitachi 50SBX70B 50" Rear Projection Television Questions & Answers

Symptom: NO PICTURE
Cause: DEFECTIVE 3D/YC COMB FILTER
Symptom: DARK PICTURE
Cause: DEFECTIVE 3D/YC COMB FILTER
Symptom: DARK PICTURE
Cause: DEFECTIVE C724

Try http://www.partmaster.co.uk

direct no longer receive pitcher or fuse in tv went bad.

Projection TV sets are known to have two common problems. The first problem that is common to these sets is convergence failure. When this happens the TV will usually look 3D, Wavy/Distorted, etc. It may also shutdown and blink an error code.

The second common problem with Projection TV sets is dull video, halos around objects, white looking video, or red overpowers the screen. This is commonly caused by the fluid in the lens being clouded overs.

You can find more details and solutions here on Fixya at the following link below. Or click HERE


http://www.fixya.com/support/r2861467-solution_video_looking_whiteish_dull

Hello,
there are 5 capacitors that were causing the problem. they might be bulged or faulty Sometimes these things can be frustrating but remember when it was so much simpler. This will require you opening the back cover of the television and having knowledge on electronics.....

bad lamp

your tv's power supply is faulty.
you will need to call a repair service out to come and have a look at it.

Yes it could cost as much as $450.00.Your set Needs Both of the STKs replaced. Hope you can solder or get someone who can, STKs are convergence ics they also control power too! If you have in your set STK392-110s use the 180s 110s do not hold up They will be big black ICs

If E994 has continuity , then C701 is ok. defective C701 gives problem with colors and picture.

If there is no led flashing, and does not turn on at all then is the power unit, test the capacitors on the power board.

There are many reasons for a no start on your 50SBX70. I will give you the most common problem I have found. Check E994( 4a pico fuse on the 120v line in pwr supply) If it is bad, remove C701(.001/2kv) from the circuit located near Q777. Inspect the capacitor for any burn marks, if so put in a new fuse and leave the cap out and fire up the set.

There is a problem with a video processing board on this set, to repair this usaly means replacing up to 30 capacitors on this board and they are all surface mounted a very fragile, bust bet on this one is to take it in to the shop

sounds like either a tube is arcing or h.o.t is arcing.

Symptom: PICTURE PULLS
Cause: DEFECTIVE D702,D703,D704
Symptom: DIGITAL CONVERGENCE WON'T ADJUST
Cause: DEFECTIVE DCU

Symptom: NO HOR SYNC
Cause: DEFECTIVE I008
Symptom: No Horizontal Sync. When PinP is called up, main picture may lock up for a 8 moment, then it goes back out of sync.
Cause: I008 defective (Sync Switch)

Double post.

Well this gives you someplace to start!
Symptom: NO POWER
Cause: DEFECTIVE I912
Symptom: SHUTDOWN
Cause: Q777,I901
Symptom: SHUTDOWN
Cause: E994,D724
Symptom: SHUTDOWN
Cause: DEFECTIVE I401
Symptom: SHUTDOWN
Cause: DEFECTIVE I601
Symptom: SHUTDOWN
Cause: DEFECTIVE C715
Symptom: SHUTDOWN/OPEN E995,E996
Cause: DEFECTIVE T702

If the green lites on bord lites up doesnt mean it is ok. If you check on that board in the middle at the back of the heatsink in the middle, there is two lights, green lights that is not lighting up. If i am wright. You have caps an a transistor on your powersup that is shorted. Take to somebody to fix powersupply.

This update covers to the following Hitachi models and chassis
46UX50B/51K, 50UX52B/53K, 60UX54B/55K, 50SBX70B, 60SBX72B, 70SBX74B. All projection televisions using the AP73 & 74 chassis's From Dennis Viereck
SYMPTOM:
Intermittent loss of Raster, On Screen Display, sometimes sound. BUT ALWAYS HAS HIGH VOLTAGE! Also removing power and reapplying it again restores operation.
THE PROBLEM: There is a lack of a secondary ground for the CRT Dag connected to each CRT board. You can identify this missing ground on the CRT board by locating two vacant pins on each CRT driver board near the CRT socket. The connector is named P801, P831, and P861 relative to each board. The pin nearest the socket is the ground pin in question. The pin furthest from the socket is connected to the cathode of the CRT.

OBJECTIVE: Run a separate ground wire from the "GROUND" pin on each CRT board to the chassis ground. You can use the circuit board mounting screw on the frame under the green CRT. See drawing below.
DIRECTIONS: Obtain 3 wires 10, 14, and 18 inches long. The wire is 18 gauge stranded with an insulated jacket. Attach one wire to each ground pin on the CRT socket. Choose the correct length of wire so that all wires will connect to the circuit board mounting screw near the center of the chassis frame.

EXPLANATION: The extra ground is needed if an internal arc occurs in the CRT. This energy must find a path to ground. Before, the only path to ground is through the signal ground wire on the RGB drive connector. This thin wire does not go directly to chassis ground and is inadequate ground for the CRT dag. If the energy level of the discharge is high enough it may corrupt the data flow on the data & clock lines or negatively effect the OSD microprocessor. Since electricity takes the shortest path to ground, the additional ground wire will route the majority of that static pulse to chassis ground quicker and reduce the possibility of corrupting operation of the OSD processor.