Question about Symphonic SC309D 9 in. TV/VCR Combo

1 Answer

Ac power Symphonic sc309D blows fuse- Dc power ok

The fuse blows instantly on the ac line, dc power works but seems to pull high current. Checked all bridge dioes and caps, none shorted. any ideas?

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

The most likely problem is a shorted diode, I suggest replacing them even if they do not test shorted while not under load. If it is not the diode rectifiers, there is probably a resister in the power supply that is shorted, remember also that it can also be both. Lastly, it can be a capacitor within the power supply.
I Wish You Well

Posted on May 01, 2009

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Ac to DC power supply


A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification. You can't run DC through a transformer to change voltage/current because it works on the building and collapsing of the field that comes with the sine wave of each phase. DC is just a straight line.

Apr 07, 2017 | Power Computers & Internet

Tip

How to test your AC/DC Adapter or Computer Power Supply Unit.


A PSU or Power Supply Unit aka AC/DC adpater is then means by which a low tension (voltage) appliance receives its power from the 240 AV mains supply, the this is usually accompanied by the nominal current that is drawn from the PSU on load in milliamps. (e.g. 500mAmps = 0.5 Amps) most modern DC adapters are unregulated, where the output voltage is only regulated by the load current, and a smoothing Capacitor is sometimes used to reduce AC ripple on the DC Level.
If the PSU is regulated the DC Voltage that you measure using an AVO even off load will be the same as the rated current.

Also most, not all, are double insulated (indicated by small square inside a larger one) this means that it doesn't need a earth on the plug, the give away is a plastic pin instead of a metal one found in most domestic plugs with a 13A fuse.

Using Ohms Law P= I x V means that we can find out either the Current in Amps Power in Watts or the Voltage of any unit this is also called the VA rating

The Simple test is if the adapter gets really hot as soon as the you apply AC power then this may indicate catastrophic failure OR a dead short and you must turn OFF immediately the plastic may even start to melt, you may also smell electrical burning. This will also happen if you ever use a non-specific adapter on your device that has a different output voltage this will almost certianly cause damage to your device.

The main test if to test the step-down transformer using an AVO (Amps Volts Ohms) this is what is used to reduce the 240V ~AC voltage to something more in line with the required DC supply say 14-16V ~AC, a diode bridge converts this to DC, if it is regualted there will be either and either a zener or resistor drops this to the rated 12V and a capacitor to smooth the level.
You need to make sure this is socket is working correctly by checking with either a lamp electricians screw driver or a AC test plug, dont use this socket you have an earth fault or someother problem, usually two lines at the outside of a AC socket tester means all is correct.
  1. First measure the resistance (Ohms) across the two AC pins that is the Live and Neutral this should have VERY low resistance in the range 300 to 2,000 (2K) Ohms. if this is the case then your primary winding is probably OK if you see 1 on all settings this means open circuit (O/C)
  2. Then connect the power supply to a 240V AC socket, and check the output voltage with multimeter set at volts DC you should see a stable voltage of the rated value for a regulated adapter or slightly higher by about 5% if its unregulated as this is a reading off load, if you were able to test the voltage with the adapter on load you would see the rated DC voltage.
  3. If you connect an unregulated AC/DC adapter to the device and open up the cover to test it under load and the voltage is low around 5V or less then the adapter will need replacing even if the off load value appears correct in above test ( ** ref the table below)
NOTE: If you have a AC only output then the test done in 1 can also be done, if there is a diode bridge, Zener Dicde OR Capacitor on the secondary this test wont work so you might have to remove the cover by unscrewing the tamper-proof screws and test it before the connection to the PCB, without the power on of course, check out my tip HERE for help on how to remove the screws.

If you have a faulty power supply its usually the thermal fuse that blows on the secondary winding, this means that you will get considerably less Voltage at the output jack of around 5 VDC or less and falling if this is the case the transformer is faulty and will need to be replaced with one of the same step-down ratio. OR you will need a new AC/DC Adapter, check out this table for examples of the results that you might find.

f9329ce.jpg

** The Amstrad Black PSU that reports 24V and 383 Ohms on the primary may still not deliver the rated voltage under load and therefore I have marked this as a false positive and therefore FAULTY.

NOTE: The AC/DC Chargers are constant current devices (the symbol is usually two interlocking circles and even though you can do similar tests on the transformer primary coil its the current that it delivers under load that is important the only way to test this is using a clamp meter on the cable to see the current under load this should match the rated current.

COMPUTER ATX PSU

Most ATX power supplies are known as switched mode can only be tested under load when connected to the PC motherboard this is a bit tricky using a plain old Fluke, AVO or Multimeter the best way is to buy dedicated PSU tester for the type of Power Unit you have, it will check the DC voltages in the range + 12V,-12V,+5V,+5VBs and +3.3V on both the SATA and IDE supply cables these cost about £20 ($35) you can test the unit in as little as 5 mins.

on May 11, 2010 | Computers & Internet

2 Answers

Why do i keep blowing the p e d fuse under the hood


What is the PED fuse, and what does it control?

May 18, 2015 | Cars & Trucks

1 Answer

Just pressure washed my recently acquired honda gb 500. and the motorcycle will not start,not even light up the dial,no neutral light,lights absolutely nothing zilch checked the main fuse that seems ok. I...


The Maine fuse is probably blown for blade fuse u can check with test light very easy same with barel fuses ohm meter work the same way except they tell voltage ohm amp on a ac or DC current battery's are DC cure plug ur red and black leads in to the meter turn it to 12v DC take the black one and ground it to frame or negative side of battery now the red one will let u fine hot wire if it's hot it will show voltage reading u can touch either side of fuse it should be hot on both sides one side should show voltage regardless with key on if fuse is blown it won't so on other side
/uploads/images/just-pressure-washed-recently-acquired-34845734-1-1.png
/uploads/images/just-pressure-washed-recently-acquired-34845734-1-2.png

Jan 06, 2015 | Motorcycles

1 Answer

Bosch 1197311213 EL14V, how can I test to determine that my alternator voltage regulator is still good or bad?


if the charge light is going out after starting then it is charging. Next step is to use a multimeter that has the ability to read volts DC and volts AC. If it shows Volts dc 13.5 to 14.5 volts at around 2.000rpms then it is good . If it shows volts ac then the rectifier in the alternator is not working and needs replacing . Next place an amp meter in the line to the battery and read the amperage .It will read in a ratio to the volts DC so if the volts Dc is up around 14.5 then the current flow will be low but if it reads 12 volts then the current will be high. If the volts dc is over 14.5 volts say 16 volts then the current will be high as the regulator is not controlling the current out put. If this sound daunting then go to an accredited auto electrical shop and have it checked out

Jul 16, 2014 | Cars & Trucks

1 Answer

WHAT ARE TRANSFORMERS


Wall socket power (high voltage) is known as AC (Alternating Current). Battery power (low voltage) is known as DC (Direct Current). Transformers are electrical converters that change AC input to DC output or DC input to AC output. This is required to charge or to supply mains power for most portable devices that use batteries when not plugged in, or devices that do not have batteries but still require DC power input. Examples of such devices are laptops, phones, tablets, printers, print servers etc. A transformer for your print server is most likely a black box in line with the power cable. In this case you will need a new power cable which will include the transformer. Some transformers are within the device itself with a power socket in the back of the device. If this is the case then replacement of the transformer (or sometimes the whole device) is required depending on the price of parts, sometimes replacing the whole device is cheaper.

Jan 15, 2014 | Lexmark N5 (12J0020) Print Server

1 Answer

Battery wont charge


Check for AC from the stator to the charge rectifier, then check for DC on the rectifier. if you have AC but no DC replace the rectifier, if you ahve no AC the stator is suspect. Assuming all fuses are checked and ok

Nov 13, 2013 | Electrical Supplies

1 Answer

I have a herritage t101, it displays the Ls error and has no drive whatsoever but was working a few month back


The SCR lower board is designed with diagnostic LED lights. The LED's are color coded according to
their specific function. Green indicates a properly operating treadmill; the green lights should always
be ON when power is supplied to the treadmill. Yellow indicates a treadmill function. Red indicates a
treadmill malfunction. Here is a list of each LED and what it signifies:
MOTOR (yellow) - The MOTOR LED illuminates when dc (direct current) voltage is sent to the drive
motor. The LED gets brighter when the dc output is increased.
RLC (yellow) - The RLC (R = Reactance / L = Inductance / C = Capacitance) LED illuminates when
the filtering system is properly working. The filtering system includes the capacitor and filter choke. If
there is a short in either component then the RLC light will not come on.
DN & UP (yellow) - The DN and UP LED lights tell us if the elevation DN and UP relays are
functioning properly. When the LED lights, it tells us that the relay has energized and is sending high
voltage (110vac or 220vac) to the elevation motor.
AC PWR (green) - The AC PWR (Alternating Current Power) illuminates when AC line voltage is
delivered to the treadmill. It then passes through the in-line fuse (110)/s(220) and lights the AC PWR
LED.
+12V (green) - When the proper AC voltage is delivered to the treadmill, passes through the in-line
fuse/s, through the full wave bridge rectifier (changes AC to DC), through the transformer (steps down
DC to +12vdc) then the +12V LED lights.
This the board LED, who control the signal for Main Motor+Elevation Motor. You must see, the LED DN+ UP( both will be Lit) in any position down or Up.
2) The RELAY board is designed with diagnostic LED lights. The LED's are color coded according to
their specific function. Green indicates a properly operating treadmill; the green lights should always
be ON when power is supplied to the treadmill. Yellow indicates a treadmill function. Red indicates a
treadmill malfunction. Here is a list of each LED and what it signifies:
AC PWR (green) - The AC PWR (Alternating Current Power) illuminates when AC line voltage is
delivered to the treadmill. It then passes through the in-line fuse (110)/s(220) and lights the AC PWR
LED.
VDC (green) - The VDC LED will light when it receives DC voltage from the DC power supply.
DN & UP (yellow) - The DN and UP LED lights tell us if the elevation DN and UP relays are
functioning properly. When the LED lights, it tells us that the relay has energized and is sending high
voltage (110vac or 220vac) to the elevation motor.
UPSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper display
board to the elevation UP relay. This low voltage dc is what energizes the coil of the relay.
DNSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper display
board to the elevation DOWN relay. This low voltage dc is what energizes the coil of the relay.
BELTSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper
display board to the belt (motor start) relay. This low voltage dc is what energizes the coil of the relay.
SPD (yellow) - The SPD LED flashes on and off (relative to speed) when the speed sensor is
operating properly.
PWM (yellow) - This LED will light when the upper board is sending a speed signal to the PWM.
Both the PWM LED and BELTSW LED must be lit for belt movement.
Finally this this Relay Board, the Each Led will be Lit, for any Relai control for DN down, or UP elevation motor. Use the contact cleaner, you can find it in R .Shack.
see the diagram attached.
God bless you1_14_2013_9_25_21_pm.png

Jan 14, 2013 | Exercise & Fitness

1 Answer

I have a reebok crosswalk rt 5.0 treadmill. I can calibrate the incline and it goes up and down. however when you press the button to raise the incline the incline number will change but the machine does...


Step 1:

see this details and proceed according. God bless you

The SCR lower board is designed with diagnostic LED lights. The LED's are color coded according to

their specific function. Green indicates a properly operating treadmill; the green lights should always

be ON when power is supplied to the treadmill. Yellow indicates a treadmill function. Red indicates a

treadmill malfunction. Here is a list of each LED and what it signifies:

MOTOR (yellow) - The MOTOR LED illuminates when dc (direct current) voltage is sent to the drive

motor. The LED gets brighter when the dc output is increased.

RLC (yellow) - The RLC (R = Reactance / L = Inductance / C = Capacitance) LED illuminates when

the filtering system is properly working. The filtering system includes the capacitor and filter choke. If

there is a short in either component then the RLC light will not come on.

DN & UP (yellow) - The DN and UP LED lights tell us if the elevation DN and UP relays are

functioning properly. When the LED lights, it tells us that the relay has energized and is sending high

voltage (110vac or 220vac) to the elevation motor.

AC PWR (green) - The AC PWR (Alternating Current Power) illuminates when AC line voltage is

delivered to the treadmill. It then passes through the in-line fuse (110)/s(220) and lights the AC PWR

LED.

+12V (green) - When the proper AC voltage is delivered to the treadmill, passes through the in-line

fuse/s, through the full wave bridge rectifier (changes AC to DC), through the transformer (steps down

Step 2:

This the board LED, who control the DC to +12vdc) then the +12V LED lights.
signal for Main Motor+Elevation Motor. You must see, the LED DN+ UP( both will be Lit) in any position down or Up.

2) The RELAY board is designed with diagnostic LED lights. The LED's are color coded according to

their specific function. Green indicates a properly operating treadmill; the green lights should always

be ON when power is supplied to the treadmill. Yellow indicates a treadmill function. Red indicates a

treadmill malfunction. Here is a list of each LED and what it signifies:

AC PWR (green) - The AC PWR (Alternating Current Power) illuminates when AC line voltage is

delivered to the treadmill. It then passes through the in-line fuse (110)/s(220) and lights the AC PWR

LED.

VDC (green) - The VDC LED will light when it receives DC voltage from the DC power supply.

DN & UP (yellow) - The DN and UP LED lights tell us if the elevation DN and UP relays are

functioning properly. When the LED lights, it tells us that the relay has energized and is sending high

voltage (110vac or 220vac) to the elevation motor.

UPSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper display

board to the elevation UP relay. This low voltage dc is what energizes the coil of the relay.

DNSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper display

board to the elevation DOWN relay. This low voltage dc is what energizes the coil of the relay.

BELTSW (green) - This LED will illuminate when the low voltage dc is delivered from the upper

display board to the belt (motor start) relay. This low voltage dc is what energizes the coil of the relay.

SPD (yellow) - The SPD LED flashes on and off (relative to speed) when the speed sensor is

operating properly.

PWM (yellow) - This LED will light when the upper board is sending a speed signal to the PWM.

Both the PWM LED and BELTSW LED must be lit for belt movement.
Finally this this Relay Board, the Each Led will be Lit, for any Relai control for DN down, or UP for elevation Motor. You must clean contact of the Relay with Special Spray(Radio Schack).

With this you must fix it.

Jan 07, 2013 | Reebok Exercise & Fitness

2 Answers

DeWalk DC500 wet/dry vaccum doesn't work


Vacuum works with the battery but does not work with 120 volt. Every time I plug it in it blows the internal fuse. I have replaced the fuse inside the vaccum several times and every time i plug it in it blows. What do you think it could be?

Feb 21, 2009 | Dewalt DC500 Canister Wet/Dry Vacuum

Not finding what you are looking for?
Symphonic SC309D 9 in. TV/VCR Combo Logo

Related Topics:

81 people viewed this question

Ask a Question

Usually answered in minutes!

Top Symphonic Televison & Video Experts

The Knight
The Knight

Level 3 Expert

72640 Answers

Henry  Thomas
Henry Thomas

Level 3 Expert

1074 Answers

SHARCNET-USA
SHARCNET-USA

Level 3 Expert

2124 Answers

Are you a Symphonic Televison and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...