Intermittent Fault on JVC Television

[Nigel]

I have a JVC AV-28F1EK, which although around 15 years old is in immaculate
condition and works well with the exception of the following fault.

It is used a spare set, primarily for my children to play their Nintendo
Gamecube.

The set will run perfectly for days and then whilst in use it will switch
off. The TV is still powered and the 'on' LED responds to the standby
button on the remote but there is no sound or picture.

If I switch off and leave for 15 or so minutes it will start working
probably for days or even weeks before the fault occurs.

There doesn't seem to be any reason to when the fault occurs. It could be 5
minutes after switch on, it could be hours.

I'm loathed to bring in a repair man because I know when he arrives it will
work fine and probably continue to do so for the next 2 weeks - so I will
end up with a call out charge and a 'no fault found'.

Anyone have any ideas?
Is this a documented problem with this set?
Can anyone point me to areas or components I should investigate/replace?

I have a good understanding of electronics (degree qualified) but don't know
televisions that well and don't have a scematic. I guess I'm looking at a
dry joint, open circuit resistor or dying electrolytic but I've no idea
where to start looking.

Any help appreciated.

Cheers,

Nigel

 

[Jerry G.]

This type of intermittent is very vague by description. You would have to
have the chassis of the set jigged up to be able to troubleshoot it. Most
likely it is a cold solder connection. You can provoke it by flexing the
circuit boards a little by applying some pressure to them while running the
chassis in the jigged up position so you can have access to both sides.

If you are not very experienced in TV service, and have the proper tools, I
suggest you give the set out to a service centre for this type of work. The
voltages employed in your set can cause injury when working on it with the
power on, which is necessary for troubleshooting most fault types. To find
these types of faults, it also takes a lot of experience. Most of the time,
an experienced tech may find this type of fault within about an hour or two.
If the set is in good condition otherwise, it may be worth to pay the cost
for this type of repair.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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I have a JVC AV-28F1EK, which although around 15 years old is in immaculate
condition and works well with the exception of the following fault.

It is used a spare set, primarily for my children to play their Nintendo
Gamecube.

The set will run perfectly for days and then whilst in use it will switch
off. The TV is still powered and the 'on' LED responds to the standby
button on the remote but there is no sound or picture.

If I switch off and leave for 15 or so minutes it will start working
probably for days or even weeks before the fault occurs.

There doesn't seem to be any reason to when the fault occurs. It could be 5
minutes after switch on, it could be hours.

I'm loathed to bring in a repair man because I know when he arrives it will
work fine and probably continue to do so for the next 2 weeks - so I will
end up with a call out charge and a 'no fault found'.

Anyone have any ideas?
Is this a documented problem with this set?
Can anyone point me to areas or components I should investigate/replace?

I have a good understanding of electronics (degree qualified) but don't know
televisions that well and don't have a scematic. I guess I'm looking at a
dry joint, open circuit resistor or dying electrolytic but I've no idea
where to start looking.

Any help appreciated.

Cheers,

Nigel

 

[Chaos Master]

I met Nigel , in sci.electronics.repair at the date of Sat, 28 Feb 2004 09:37:28
-0000, when we had ideas of posting and reading in the article

Anyone have any ideas?
Is this a documented problem with this set?
Can anyone point me to areas or components I should investigate/replace?

I have a good understanding of electronics (degree qualified) but don't know
televisions that well and don't have a scematic. I guess I'm looking at a
dry joint, open circuit resistor or dying electrolytic but I've no idea
where to start looking.

Likely a cold solder joint. If you don't have experience in TV repair, send it
to a tech which has experience with TV's. This fix is not something very
complicated - an experienced tech can do it in 1 hour or so.


--
by Chaos Master® - MSN: [email protected]

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Na-chaered palan-diriel o galadhremmin ennorath,
Fanuilos, le linnathon nef aear, si nef aearon!" - The Lord of the Rings

Linux User #327480 / GNU-Win32 / Cygwin / Win98 + LiteStep

 

[David]

Almost all intermittent problems on a set this old fall into one of two
categories, solder connection problems or weak/high esr capacitor related
problems.

A well experienced tech should have no problem tracking the issue down once
he is able to duplicate the failure. It may require a couple of hours with
the tv apart and set up while it is running. It might be beneficial to
simply take the tv into the shop so they can do a complete run test under
controlled environment in case it does not act up within the first couple of
hours. You typically save 20% of the total repair cost on a problem like
this if you take the tv in to the shop rather than having an in home repair
attempt.

David