Sanyo TV Service Mode

The procedure for entering the service mode on a Sanyo TV:

1. Press/hold "Menu" button on the TV front controls.
2. Point the remote control to the TV. Press "2" button on the remote. The service menu will appear on the TV screen.
3. Press Channel +/- to select adjustment item.
4. Press Volume +/- to adjust data/settings.
5. To exit: Press "Menu" on TV front control.

The service mode allows the TV technician to adjust picture geometry, RGB settings, TV features and hardware configurations. 

Always record the present settings before adjustment so you can return the settings should adjustments causes more problems.

It would be easier for you to set adjustments if you have a record of the factory default settings for the particular model of TV you are working on.

Philips TV 21PT128A/71R: Irregular picture size & shape problem

A TV repair problem that I had recently encountered is with a Philips 21PT128A/71R which exhibited irregular picture size and shape.

TV troubles like this usually indicates a problem with filter capacitors so I visually checked electrolytic capacitors on the main PCB.
One electrolytic capacitor on board location C2453 looked suspicious with its slightly bulging top. Checking the part using a capacitance meter, it read 3 microfarad instead of its indicated value of 680uF/35V.
 I replaced the capacitor with an available part on hand with a value of 1000uF/50V which restored normal size and shape to the picture.
The capacitor is a filter for the +25V scan-derived supply from the flyback transformer.

Samsung TV CS-29Z58MQ: three colored lines on top of picture

I have recently encountered in my repair work a Samsung Slim Fit CRT TV model# CS-29Z58MQ with a problem of three horizontal blanking lines appearing at the top edge of the screen. According, to the customer the problem started with just one line but after some time an additional two lines also appeared on the edge of the picture.
I inspected the board and tried to spot some bulging capacitors with signs of electrolyte leakage which usually cause this kind of picture abnormalities but found none.
Upon closer inspection of the solder side of the main board I saw signs of dry solder on resistors R428 (1.5 ohms, 1W) and on R413 (1ohm, 1W). These two resistors are connected in series with the Flyback transformer's 16.5V supply pin to the vertical output IC LA78045. The resistors are located at the rear edge of the main board beside the flyback transformer.
After resoldering the dry solder on the resistors the three colored lines on top of the picture disappeared.

Daewoo TV DTQ-2072 repeated blowing of fuse

Where can the problem be if the main fuse in the TV power supply blows fuse repeatedly?
This was a problem I have encountered with a Daewoo TV model# DTQ-2072. The fuse blows even when the IC regulator  STR-59041 has been replaced. To isolate the cause of the problem, I replaced the fuse again and disconnenected the PTC thermistor on board location RH02.
I plugged the set to AC outlet and powered up the set from standby. The picture and sound came up but the picture has color smears(dynamic misconvergence) on the sides of the screen - a result of disconnecting the thermistor which passes momentary current to the degaussing coil.
An ohmmeter check on the thermistor shows that it has developed a higher resistance. Opening the plastic case of the PTC thermistor revealed that the thermistor discs are burnt.
Replacing the PTC thermistor eliminated the  color stains on the picture and solved the problem of  blowing of fuse.

Hot /Cold Water Dispenser Parts and Functions

Because of the popularity of water from refilling stations which comes in plastic gallons the hot/cold water dispenser has become an indispensable appliance in the home today.
Let us know the important parts of the water dispenser and the function of each..

Chiller Tank

A stainless tank with an evaporator coil wound around its side for cooling the water. The evaporator coils are similar to the that used inside refrigerator freezers.

 

 

Heater Tank

A stainless enclosed tank with internal heaters for heating the water inside the tank and insulated with foam to conserve heat.

The heater tank includes an internal heater drawing at least 2 amperes of current to bring the water temperature up to boiling point.

Silicone Tubings

The water is channelled from the tanks to the dispenser faucets via silicone tubings. The silicone tubings are soft and flexible and resistant to hot and cold temperatures.

Heater Thermostat  

The heating tank thermostat's cutoff termperature is rated below near the boiling point of water which is 100 deg. centigrade. The thermostat will become open circuited when water inside the heating tank starts to boil. It is to prevent overheating which can damage the heating tank.

Water Tap/Valves 

 

Hot/Cold Water Dispenser On-site Repair Home Service in Metro Manila

Hotline: +63926.535.6848 (text/call)

Promac LCD-2051 power problem

Promac LCD TV model# LCD-2051 powers up from stand-by, sound comes up and backlight lights up but set goes back to stand-by before picture appears.
Found some bulging 47uF/16V capacitors on power supply board on location C3 and C8. Replacing the capacitors restored normal operation to the set.

Sony TV KV-21GMR1 power problem:SE115N error amp defect

Sony TV model# KV-21GMR1 is a dead set: no LED standby indicator light, +115V supply to horizontal output transistor measured only 27V and is pulsating.
The SMPS regulator IC STR-S6707 was replaced but still the +115v supply line is dropped.
Even when the horizontal output transistor is disconnected from the circuit the +115V supply will not increase.
An ohmmeter check on the SE115N error amplifier shows that it is internally open circuited.
Power was restored to the set when the SE115N was replaced.