Philips 17" (17C6811N) Monitor Arcing on CRT yoke

T

TEX

Guest
Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the arcing.

Thanks

TEX
 
TEX wrote:

Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the
arcing.

Thanks

TEX
Click to expand...

Also noticed a noticable electrical shock when touching the front of the
crt. Like those barbque starters.

TEX
 
The CRT may be defective, and not properly loading, or the HV multiplier has
too high an output. The CRT board, and or the socket on it may also be
damaged by now.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"TEX" <TEX@Nospam.com> wrote in message news:3fc43426$1@news.iconz.co.nz...
Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the arcing.

Thanks

TEX
 
Tex, sounds like the the focus pot on the FBT has gone o/c.This is a common
fault and causes these symptoms.
Cheers
Joe
"Jerry G." <jerryg50@hotmail.com> wrote in message
news:bq1sbf$t71$3@news.eusc.inter.net...
The CRT may be defective, and not properly loading, or the HV multiplier
has
too high an output. The CRT board, and or the socket on it may also be
damaged by now.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"TEX" <TEX@Nospam.com> wrote in message
news:3fc43426$1@news.iconz.co.nz...
Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the
arcing.

Thanks

TEX
Click to expand...
 
The socket and board looks fine. No visable signs of damage or over
heating at all. Is there a prefered way to test if the focus pot is
o/c?? Normally I don't bother fixing anything which is related to FBT.

Thanks

TEX

Pussynuts wrote:

Tex, sounds like the the focus pot on the FBT has gone o/c.This is a common
fault and causes these symptoms.
Cheers
Joe
"Jerry G." <jerryg50@hotmail.com> wrote in message
news:bq1sbf$t71$3@news.eusc.inter.net...

The CRT may be defective, and not properly loading, or the HV multiplier

has

too high an output. The CRT board, and or the socket on it may also be
damaged by now.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"TEX" <TEX@Nospam.com> wrote in message

news:3fc43426$1@news.iconz.co.nz...

Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the

arcing.

Thanks

TEX
Click to expand...
 
Measure the focus voltage at the CRT socket with a high-voltage probe.
I'll bet that it is 20 KV or more. (Should be less than 10 KV, usually
3 to 6 KV).
The focus pots on the flyback are probably bad letting too much of the
high-voltage into the focus circuit, which is causing the sparking
at the crt socket. You have to replace the flyback transformer.
Hope this helps...
John


TEX <TEX@Nospam.com> wrote in message news:<3fc43426$1@news.iconz.co.nz>...
Was working fine, then it started clicking like crazy. Thought is was
the SMPS clicking, but when opened it up found that the board on the end
of the CRT was arcing out. There is two lines from the FBT (red and
white) that feed the base of the CRT that seem to be arcing out.

Whats is the story with this??? Never seen anything like this before.
Faulty FBT???. The tube does light up, but flickers in time with the arcing.

Thanks

TEX
Click to expand...
 
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