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Sony Trinitron model KV-19TS20

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Glenn Russell

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May 26, 2015, 4:46:05 PM5/26/15
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My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?

rev.11...@gmail.com

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May 26, 2015, 6:38:17 PM5/26/15
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On Tuesday, May 26, 2015 at 1:46:05 PM UTC-7, Glenn Russell wrote:
> My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?

What have you tried on it so far?

captainvi...@gmail.com

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May 27, 2015, 2:30:53 PM5/27/15
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On Tuesday, May 26, 2015 at 4:46:05 PM UTC-4, Glenn Russell wrote:
> My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?

Try this first. Pull the chassis and resolder anything that looks suspicious, especially around the hor. output area. Lenny

J.B. Wood

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May 28, 2015, 6:38:49 AM5/28/15
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Hello, and that sounds like a classic horizontal sweep problem. For
whatever reason(s) the horizontal section is not generating the proper
sweep waveform and since this section also provides high-voltage to the
CRT (Picture Tube), the combined effect is evident on the screen. The
high-pitched sound is coming from the vibrating core of the horizontal
output (flyback) transformer. The flyback or horizontal output power
transistor feeding the flyback could be bad or something else like a
cold solder joint(s) might be the issue. Sincerely,

--
J. B. Wood e-mail: arl_1...@hotmail.com

RobertMacy

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May 28, 2015, 8:28:56 AM5/28/15
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On Thu, 28 May 2015 03:38:45 -0700, J.B. Wood <arl_1...@hotmail.com>
wrote:
If that is like the trinitron that gave me trouble, YES check the
Horizontal Sweep Section. The design there seems marginal, runs HOT, and
appears to 'kill' the output transistor, but replace its driver too while
you're in there. Why? 1. you're in there, and 2. When the output
Transistor went, it takes the driver, or at least greatly weakens it.
And, Why not rpelace it? What is saved by being cheap? PS: don't know if
related, or cause, but one of the blocking caps was leaky and had to be
replaced. I found out because the 'fix' of changing only output
transistors lasted a few months before all wonky again.



Chuck

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May 28, 2015, 12:06:32 PM5/28/15
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Make sure to resolder the horizontal driver transformer leads. If
there is an electrolytic capacitor connected to the H drive circuit,
replace it too.

---
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http://www.avast.com

J.B. Wood

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May 28, 2015, 12:34:03 PM5/28/15
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On 05/28/2015 12:06 PM, Chuck wrote:

Hello, again, and in assuming that the OP still has a properly sized
picture with exception of the artifacts at the edges of the screen, what
may be occurring is arching due to insulation breakdown in the flyback
transformer, high-voltage rectifiers or other components that have to
withstand many kilovolts. A strong scent of ozone in the horizontal
section might be an indication. Just another consideration in addition
to those who previously provided timely troubleshooting tips. Sincerely,

jurb...@gmail.com

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May 29, 2015, 8:14:20 PM5/29/15
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On Tuesday, May 26, 2015 at 3:46:05 PM UTC-5, Glenn Russell wrote:
> My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?

What about the bad connections at the coils to the IF chip. Nobody mentioned that.

Chuck

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Jun 2, 2015, 9:13:54 AM6/2/15
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You are right. Also the bad grounds in the tuner.

captainvi...@gmail.com

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Jun 2, 2015, 9:45:21 AM6/2/15
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On Tuesday, May 26, 2015 at 4:46:05 PM UTC-4, Glenn Russell wrote:
> My vintage Sony Trinitron model KV-19TS20 goes wacky after inly a few seconds. screen has jagged lines and makes a noise that changes in pitch from low to high. Can somebody please help me?

Tuner grounds? You may be thinking of RCA

John-Del

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Jun 2, 2015, 10:29:13 AM6/2/15
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Sony tuners were not immune to bad grounds, particularly the combo tuner/IF modules, although they were no where as troublesome as those RCA CTC17X series.

Chuck

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Jun 2, 2015, 7:10:07 PM6/2/15
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On Tue, 2 Jun 2015 07:29:10 -0700 (PDT), John-Del <ohg...@aol.com>
wrote:
At the Sony warranty station where I worked there were so many sets
returning with tuner ground failures, that it got to the point,
regardless of what the set was brought in for, we resoldered the tuner
grounds as well as all IF and AFT transformer leads.
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