STR G5653 - BASED TV SMPS SCHEMATIC [Circuit Diagram]
CLICK ON THE SCHEMATIC TO ZOOM
Check the resistance across pin-1 & pin-3 of STR
G5653. It should be high. If found very low, or absolutely zero Ohms,
the STR is short. If this is the case,
the main fuse will blow up. Check whether there is any loose solder terminals
to C-810(390pf 2Kv.) It is a critical component
to be noted, before replacing the STR.
Check the Zener diodes VD812, VD815 for any short or leak. It will be best to replace recommended. Check
all the four main rectifier diodes too. [VD801, VD802, VD804 &
VD805. Replace these four diodes if any
one found faulty. If STR is shorted,
surely the R803 (0.22Ohms) will be opened.
Replace it. In most cases, the short of STR might caused an internal
damage to the V802 (HS817) opto-coupler.
It will be best to replace it too, with same number used. - The TV has a nominal working EHT voltage. Extreme caution should be exercised when working on the TV with the back removed.
- Do not attempt to service this TV if you are not conversant with the precautions and procedures for working on high voltage equipment.
- When handling or working on the CRT, always discharge the anode to the TV chassis before removing the anode cap in case of electric shock.
- The CRT, if broken, will violently expel glass fragments. Use shatterproof goggles and take extreme care while handling.
- Do not hold the CRT by the neck, as this is a very dangerous practice.
- It is essential that to maintain the safety of the customer all power cord forms be replaced exactly as supplied from factory.
- Voltage exists between the hot and cold ground when the TV is in operation. Install a suitable isolating transformer of beyond rated overall power when servicing or connecting any test equipment for the sake of safety.
- When replacing ICs, use specific tools or a static-proof electric iron with small power (below 35W).
- Do not use a magnetized screwdriver when tightening or loosing the deflection yoke assembly to avoid electronic gun magnetized and decrement in convergence of the CRT.
- When remounting the TV chassis, ensure that all guard devices, such as nonmetal control buttons, switch, insulating sleeve, shielding cover, isolating resistors and capacitors, are installed on the original place.
- Replace blown fuses within the TV with the fuse specified in the parts list.
- When replacing wires or components to terminals or tags, wind the leads around the terminal before soldering. When replacing safety components identified by the international hazard symbols on the circuit diagram and parts list, it must be the company-approved type and must be mounted as the original.
- Keep wires away from high temperature components.
- Many electrical and mechanical components in the chassis have special safety-related characteristics. These characteristics are often passed unnoticed by a visual inspection and the X-ray radiation protection afforded by them cannot necessarily be obtained by using replacements rated at higher voltages or wattage, etc. Components, which have these special safety characteristics in this manual and its Substitute replacement components, which do not have the same safety characteristics as specified in the parts list may create X-ray radiation.
- Do not slap or beat the cabinet or CRT, since this may result in fire or explosion.
- Never allow the TV sharing a plug or socket with other large-power equipment. Doing so may result in too large load, causing fire.
- Do not allow anything to rest on or roll over the power cord. Protect the power cord from being walked on, modified, cut or pinched, particularly at plugs.
- Do not place any objects, especially heavy objects and lightings, on top of the TV set. Do not install the TV near any heat sources such as radiators, heat registers, stove, or other apparatus that produce heat.
- Service personnel should observe the SAFETY INSTRUCTIONS in this manual during use and servicing of this TV set. Otherwise, the manufacturer does not protect the resulted damage.
