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Transformer do not output voltages, d1710 and other components are ok, 4.8k ohm (10watts) is hot, no shorts on the B+ and other circuits.

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SOURCE: Sanyo ST-21G1 dead set

There should be a small valued cap in the primary side (22ufd?) at 250V. Check that. Also, look for other small caps int he range of 2.2ufd with 200V ratings in the same general area.

Posted on May 07, 2008

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Confirmation: Lee2fixit's solution also worked on a Sanyo 19" TV Model DS19580with 'buzzing relay'. Chassis carriessimilar relay (Type DG1U 12VDC II TV-5 8A 250V~ also by DEC) at location RL601and a 25VDC 470uF electrolytic cap at C622. After confirming the relay was sound and finding no obviously faultedcomponents tied to it, replaced the cap. Bingo, normal operation and a quiet relay. Will post a follow-up ONLY if the fix failsbefore the rest of the TV .. it's almost10 years old after all. Thank youLee2fixit and

Posted on Mar 05, 2009

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The screen on my sanyo box TV model number DS27510 starts shaking and the picture starts cutting in and out anyway to fix??

Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Pull up older posts.
Type in this key phrase " my service table today " in the search box at the top right of the display window of the home page, to get gathered some pages which has the details of practical experiences to the author of that site.

Apr 10, 2016 | Sanyo Standard (CRT) Televisions

2 Answers

What is the main cause of this problem stand by light flashing

Short circuit indication. There should be a short circuited component/s at its main board. Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.

Jan 20, 2015 | Standard (CRT) Televisions

1 Answer

There is a malfunction in the THT

Hi Hashim.
EHT (Extra High Tension) usually reefers to the 24kv to 30kv, focus and first anode (A1) voltages required to operate the crt (picture tube). These voltages are supplied by the line output stage, primarily the line output transformer (often refered to as the flyback transformer). This transformer steps the voltage up to 8kv and an embedded rectifier trippler circuit tripples this to 24kv dc to supply the final anode voltage to the tube (Hence the big rubber cap and thick cable.
The line output transformer is driven by a smaller transformer (line driver transformer) via the line output transistor.
The driver stage is fed by the hoizontal oscillator circuit.
So we can see that a failure in any part of this circuitry will most often result in no picture. The line output transformer is the heart of the system, it not only supplies the EHT voltage it also has to
supply an LT voltage for the vertical output stage but also the sound output stage.
A Fault in the A1 circuitry would result in a very dark picture but sound ok. Or the picture badly out of focus.
The line output transistor going short circuit results in no picture and no sound with the set shutting down to the standby mode or
hic upping (making a ticking noise. This problem would be amongst the most common and is easily confirmed with an Ohm meter. The line output transformer itself can develope an internal short with the same results (less common). Failure of the line oscillator and driver stages are most easily confirmed with an
oscilloscope. A fault in the power supply will also give these symptoms. To confirm line output stage is functional look to see if the tube heaters are glowing, this supply also comes from the line output transformer. Can you feel the static if you run the back of your hand across the front of the screen (often feels like running your hand through cobwebs. this would indicate that the EHT is present and the fault is elsewhere. Understanding how something
works enables you to find out why it doesn't. If you have occasion to replace a short circuit transistor, be sure to reslder all pin connections to the line driver transformer. I've found dry joints here
to be a cause for random inttermittent failure of this transistor,
Best regards from Vintie.

Jan 07, 2014 | Sony WEGA® KV-XR25M80 TV

1 Answer

Tv model #46h84 wont turn on no picture or sound

Assuming thar you can open the tv case and deal with electronic parts, you should first check the main fuse. If it is OK, check the anti-surge resistor (generally 3,3 Ohms/5W). One of these components may be bad. Before replacing the bad one, check for short in MOSFET power switching transistor, fast output rectifier diode (+ or - 90V line voltage). After findind out the culprit replace the bad components a afterwards plug in the tv and test.

Good luck. I hope this will help you.


Sep 25, 2013 | JVC AV-A21M3U 21" TV

1 Answer

No horizontal and vertical deflection available:- audio OK

Check its horizontal output stage circuit. Replace damaged component/s. Vertical output stage gets its working voltage from the horizontal output transformer. If you want to get vertical deflection, this transformer, otherwise known as {LOT] should work to produce the supply voltage to vertical output stage.

Oct 12, 2012 | Panasonic CT-2789VYD 27 inch TV

1 Answer

I have a Sylvania TV, Model #SRT2232S that won't turn on but havee clicking sound in back

The LOT [Line Output Transformer] of your TV. It should be replace with same type and number. Actually this is a skilled work. You have to unsoder this component out from the circuit board, and to resolder the new one in place. Have to adjust the perfect screen and focus voltage. Screen and focus voltage controls can be seen on it. This component can be bought from most of the electronic spare part shops at your tow. The number printed on it is important and should be noted. The sample picture of that component is attached here. This component also known as Flyback transformer. OK.


Oct 01, 2011 | Sylvania SRT2232S 32" TV

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The tv is a 32"

The horizontal output transistor of your RCA TV has shorted. Horizontal output transistor is one, that drive the Line Output Transformer [LOT] in short, which gives voltages requred to the picture tube of your tV. There are mainly two resons for this transistor shortage. If the above said LOT has shorted [a winding short in between at its inner side; and is irreparable]; and for some other reasons which cannot be predicted. First replace this transistor, which can be located very near to the LOT and will be screwed onto a metal heatsink to radiate heat away from it while working.
It will be three terminal black component. Replace it with same type and number, and switch ON your tV for a short time, say 4 seconds or so; unplug the device from AC mains wall socket, touch the replaced component with bare fingers and feel the heat. It may be slight warm, bu not too hot. If LOT has damaged, this transistor also will heat up, and a whisiling sound will be there. If so; never switch it ON again; replace the LOT and it is damaged. OK.

May 28, 2011 | RCA TruFlat 27F520T 27" TV

2 Answers

Sharp tv primo 21`inch turn on red light only

check your horizontal transistor maybe it's shorted replace horizontal transistor or maybe the fusible fuses are open check for open resistors at the horizontal section of the circuit.

Dec 22, 2010 | Sharp Standard (CRT) Televisions

1 Answer


Hello valexandrur,

You are in the correct section, now your problem may be a shorted Integrated High Voltage Transformer (IHVT) also called a Fly-back Transformer and or a shorted Horizontal Output Transistor (HOT). I would first check the Transistor to see if it is shorted between the emitter and collector (to do this use a multimeter set to "Rx1") and the reading between the emitter and collector should be near infinite no reading, if the reading is 000 ohms then the transistor is shorted and should be replaced. Now for the hard part, you technically can not check for shorted transformer turns in the IHVT using a multimeter, you will have to use a device which will allow you to do what is called a ring test. If you do not have this piece of equipment (IHVT tester), I would replace the IHVT just as a matter of good measure, since the HOT had drawn a lot of current I would assume that the IHVT was damaged to since it is in the serial path between the collector of the transistor and the VCC supply.

I hope this helps,

Thank you,


Jan 19, 2009 | Proton MM2701VT 27" TV

4 Answers

Tv trouble shooting

whenever any fusible resistance fails means there is a short ckt in tv. failure is mainly due to main filter cap or rectifire diode os switching ckt failure(here as you cleared str.) remember while servicing power supply isolate hor. section for safety purpose.& connect it only after power supply output is ok &after checking parts in hor. ouyput section. if this seems to be ok then go for hor.output ckt failure like hor output,flyback transformer & cap& diodes connected with it.

Oct 02, 2007 | Standard (CRT) Televisions

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