Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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Jason D.
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

Great, it was working. But the saga doesn't end there...

After plugging the unit back into my home entertainment center (which
consists of a Dish DVR-Symphonic DVD/VCR combo-Gamecube-RCA 27" TV)
with this configuration, the TV fuse immediately blew.

Without delving into it, my friend guesses that there's a small
voltage in the line, and that the blue filters (and whatever else is
in the sheilded coax assembly) is filtering the stuff out. Since we
bypassed this filter mechanism, the fuse blows.


This design of chassis is HOT and direct connected to power. This is
why this input is isolated. Get this part repaired properly not
bypassing. Bypassing is good for diagnostic purposes.

I think there is more damage now :-(

Cheers,

Wizard


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David
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

I am SURE there is significant more damage now.
I have seen the ctc185 become not practical to repair after this "dumb
ass","stupid idiot" type of "fix" done by someone who thinks they know
electronics. If upon inspection by a qualified technician, any of the
grounds inside the tv are found burnt, it is toast and not going to be
practical to repair. Seen it too many times on the ctc185 chassis.

It was a SIMPLE fix with the proper connector, equipment, and skills when
the connector was just loose.

David

"Jason D." wrote in message
...
Great, it was working. But the saga doesn't end there...

After plugging the unit back into my home entertainment center (which
consists of a Dish DVR-Symphonic DVD/VCR combo-Gamecube-RCA 27" TV)
with this configuration, the TV fuse immediately blew.

Without delving into it, my friend guesses that there's a small
voltage in the line, and that the blue filters (and whatever else is
in the sheilded coax assembly) is filtering the stuff out. Since we
bypassed this filter mechanism, the fuse blows.


This design of chassis is HOT and direct connected to power. This is
why this input is isolated. Get this part repaired properly not
bypassing. Bypassing is good for diagnostic purposes.

I think there is more damage now :-(

Cheers,

Wizard




  #3   Report Post  
Jason D.
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

On Sun, 25 Jul 2004 20:40:00 -0500, "David"
wrote:

I am SURE there is significant more damage now.
I have seen the ctc185 become not practical to repair after this "dumb
ass","stupid idiot" type of "fix" done by someone who thinks they know
electronics. If upon inspection by a qualified technician, any of the
grounds inside the tv are found burnt, it is toast and not going to be
practical to repair. Seen it too many times on the ctc185 chassis.

It was a SIMPLE fix with the proper connector, equipment, and skills when
the connector was just loose.

David


Hmmm That's true. This is very unique for RCA to design CTC185 back
then. Now this design is not used anymore by RCA. RCA has chassis of
all kinds are currently used that partially isolates main power from
rest of chassis but techincally chassis is still "hot" but very local
to the SMPS hot side but not so destructive as CTC185 was.

Cheers,

Wizard
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Ken Weitzel
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)



Jason D. wrote:
On Sun, 25 Jul 2004 20:40:00 -0500, "David"
wrote:


I am SURE there is significant more damage now.
I have seen the ctc185 become not practical to repair after this "dumb
ass","stupid idiot" type of "fix" done by someone who thinks they know
electronics. If upon inspection by a qualified technician, any of the
grounds inside the tv are found burnt, it is toast and not going to be
practical to repair. Seen it too many times on the ctc185 chassis.

It was a SIMPLE fix with the proper connector, equipment, and skills when
the connector was just loose.

David



Hmmm That's true. This is very unique for RCA to design CTC185 back
then. Now this design is not used anymore by RCA. RCA has chassis of
all kinds are currently used that partially isolates main power from
rest of chassis but techincally chassis is still "hot" but very local
to the SMPS hot side but not so destructive as CTC185 was.

Cheers,

Wizard


Not to mention that the "electronics instructor" at the
local community college would be far far better suited
to employment in the janitorial department.

Think if I were the OP I'd contact my lawyer and the
community college.

Ken

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Art
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

IMHO: First lesson any "Electronics Teacher/instructor" has to absolutely
know is the fact that safety first is mandated. If they are unsure of a
circuit design regarding isolation, they too are lacking in knowledge. The
oblivious results are already indicated within your original post. I don't
know how many times it is stressed within the service manuals, schematics,
and multiple printed materials regarding servicing any type of electrical
equipment. Confirming proper electrical hookup and isolation of the device
is absolutely mandated. This is one or the initial lessons that any
competent Electrical/Electronics Teacher must inbed in their students, and
follow the principle theirselves. BTE Jerry Greenberg has an excellent site
that explaines this information in depth, doing a 'google or yahoo' will get
you there.
"Ken Weitzel" wrote in message
news:yr_Mc.109923$Mr4.18557@pd7tw1no...


Jason D. wrote:
On Sun, 25 Jul 2004 20:40:00 -0500, "David"
wrote:


I am SURE there is significant more damage now.
I have seen the ctc185 become not practical to repair after this "dumb
ass","stupid idiot" type of "fix" done by someone who thinks they know
electronics. If upon inspection by a qualified technician, any of the
grounds inside the tv are found burnt, it is toast and not going to be
practical to repair. Seen it too many times on the ctc185 chassis.

It was a SIMPLE fix with the proper connector, equipment, and skills

when
the connector was just loose.

David



Hmmm That's true. This is very unique for RCA to design CTC185 back
then. Now this design is not used anymore by RCA. RCA has chassis of
all kinds are currently used that partially isolates main power from
rest of chassis but techincally chassis is still "hot" but very local
to the SMPS hot side but not so destructive as CTC185 was.

Cheers,

Wizard


Not to mention that the "electronics instructor" at the
local community college would be far far better suited
to employment in the janitorial department.

Think if I were the OP I'd contact my lawyer and the
community college.

Ken





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Leonard Caillouet
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

Doesn't everyone perform a leakage test before giving equipment back to a
consumer? You know, grab ground with one hand, lick your finger, then touch
all the exposed metal parts to verify less than 500uA current...it weeds out
the incompetents...

Leonard

"John Del" wrote in message
...
Subject: 27" RCA TV reception problems and other stuff (F25281,
CTC185AB9)
From: Ken Weitzel
Date: 7/26/04 2:58 AM



Not to mention that the "electronics instructor" at the
local community college would be far far better suited
to employment in the janitorial department.


And to further mention that by giving the TV back to the OP with the tuner
input now "hot" to the AC line by his "fix", he could have killed him.

John



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RonKZ650
 
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Default 27" RCA TV reception problems and other stuff (F25281, CTC185AB9)

You are one lucky dog. I have seen too many ctc185 short the hot
ground to ac/cable ground cause big time major problems.

It is a $7.00 connector from Thomson, and good soldering equipment is
all that is required.


It's a miracle actually. 99% of the time if the connector is shorted to the hot
chassis on top of destroying the chassis, even the CRT filiments are burned
out. I wonder why the CTC175 with the hot chassis is never damaged the way the
185 is.
Ron
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