[TechAssist] Re: Mitsubishi QV10 Chassis Rear Projection.
- From: Phil Bader <tjanphyl@xxxxxxxxxxxxxxx>
- To: techassist@xxxxxxxxxxxxx
- Date: Thu, 02 Jun 2005 16:40:34 -0400
Here's a bunch of "no video" fixes I found from my techRepairCD
(jeff@xxxxxxxxxxxxxxxxxx)
MITSUBISHI~VS5007R~No Video/Hv Ok~~~~Check Screen Supply Resistor R511
For Open. Located On Pcb-Main Off Fbt Pin 1. (100 Ohm 1/2w Fusible) Pt
# 103p39103~~~~~~
MITSUBISHI~VS5007R~NO VIDEO* NO AUDIO~~~~OPEN R540(1.2-1/2W FUSIBLE)..NO
VCC TO VERT OUT(IC401)~~~~~~
MITSUBISHI~VS5007R~No Video All Inputs~~~~Missing Video At Pin 1 Of
Ic7602. Confirm 1vpp Tuner Video At Pin 4 And 5vdc At Pins 2 And 3.
Pcb-Signal Part #272p394010~~~~~~
MITSUBISHI~VS5007R~No Vertical Deflection~~~~Check Pin 8 Of Ic401 For
28.4v. If Missing Check For Open D520 And R540 At Pin 5 Of Flyback.~D520
Part #264p102020 R540 Part #103p398010~~~~~
MITSUBISHI~VS5007R~No Tuner Video Or Audio~Missing Agc Voltage At
Tuner~~~Check For Shorted C106 (0.1uf 50v) At Pin 6 Of Ic101.
Pcb-Signal~~~~~~
MITSUBISHI~VS5007R~No Tuner Video Or Audio~Missing 9vdc At Pin 21 Of
Ic101.~~~Open Ic709 9v Regulator Off Pin 21. Pcb-Signal Part#
266p931010~~~~~~
MITSUBISHI~VS5007R~Intermittent Video~On Screen Display Is Good.~~~Check
For Defective 5v Regulator Ic7007. Located On Pcb-Video(Pip). Pt#
266p93406~~~~~~
MITSUBISHI~VS5007R~Intermittent Video~~~~Suspect Defective 5v Regulator
Ic2002. Located On Pcb-Video. Pt# 266p923040~~~~~~
MITSUBISHI~VS5007~INTERMITTENTLY LOOSES VIDEO* CHROMA OK* PIC GETS
DARK~~~~SOLDER R7400* NEAR IC7007~~~~~~
MITSUBISHI~VS5007R~No Y (Color Present)~No Luminence At Pin 12 Of
Ic2a01~~~Confirm Luminence Input At Pin 5 And 9.3vdcc At Pin 4. Replace
Ic2a01. Pcb-Video Part #266p064010~~~~~~
MITSUBISHI~VS5007R~No Y (Color Present)~~~~Suspect Leaky/Shorted Video
Buffer Q229. Located On Pcb-Main At De Connector Pin 4. 2sc1740s Pt#
260p559030~~~~~~
MITSUBISHI~VS5007R~No Y (Color Present)~~~~Suspect R511 For Open/Raised
Value. Located On Pcb-Main At Fbt Pin 1. 100 Ohm 1/2w Fusible Pt#
103p391030~~~~~~
MITSUBISHI~VS5007R~NO VIDEO* NO AUDIO~~~~OPEN R540(1.2-1/2W FUSIBLE)..NO
VCC TO VERT OUT(IC401)~~~~~~
HTH
Phil Bader
Philip Bader
Jan Phyl TV Inc. (estab. 1976)
3420 Recker Hwy. Winter Haven, Fl. 33880
Fax (863) 299-8821
email: tjanphyl@xxxxxxxxxxxxxxx
Tel-Tek wrote:
>I guess the Model Number is not worth mentioning, since it's an
>Electrohome but just in case it's PROH50, and very similar to VS-5007.
>
> This set came in with the Vertical O/P (LA7838) blown. Replace it and
>all caps, HV came back up..along with sound.
>
> I have no Video and also no voltage (11.8 volts) on pin 1 of LA7838. I
>presume Beam Limiter/Protector has kicked in. Found a few bad caps in
>that circuit with C5002 10/50volts just about eaten away.
>
> Some of the transistor in that circuit are Q503 Q504 Q507 Q508.
>
> If anyone has wrestled with this circuit, with good results..LMK.
>
>May be just that I'm missing my 12 Volts, but have no idea where it
>comes from.
>
> Also does anyone know how to temporarily defeat this Beam Limiter
> circuit.
>
>Thanks..
>
>-Ed-
>
>
-----------------------------------------------------------------------------
This Email List is Public. Remove: http://www.tech-assist.org/remove.htm
Lost Password: http://www.tech-assist.org and select "Login Problems?".
Appliance Repair List: http://www.tech-assist.org/secure/tip/chatjoin.htm#app
Email Archives: //www.freelists.org/archives/techassist/
Other related posts:
