TV stopped responding after RCA universal remote
 

I posted about this earlier (Hitachi CT7883) with the original Video Brain
Remote Transmitter CLU-600PR which broke down over time. The Hitachi VCR
remote control, however, could still control the television perfectly!

But * after * trying an RCA universal remote, the television stopped
responding entirely to even the good remote control. Now I have obtained a
factory remote replacement as per Hitachi's tech support and even this can
not control the television set. The TV stopped responding to remote
controls.

I'm quite certain that the programming efforts of the universal remote put
the TV into a bad state. If I can clear the nonvolatile memory somehow,
this should fix things. But even leaving the TV unplugged had no success.

Any ideas? Is there anything else I can do, short of calling in a repair
person to look at a 13 year old TV set?

--
Jem Berkes
http://www.sysdesign.ca/

Failure in the IR Pickup circuit, or anything between it and the MPU
inclusive of stuck or corroded tac switches. Due to the age even leaky
diodes or other components going bad will affect these operations. Start by
checking the operating potentials at the IR Pickup and confirm indeed it is
picking up and transferring the signals from the remote. If so then trace
that signal all the way to the MPU. Severe clipping or loss of the Control
Signals from the IR Pickup while in route to the MPU will affect its
functions. IMHO it is highly unlikely that you have changed any data
parameters when using the universal remote that will result in this symptom.
"Jem Berkes" wrote in message
.. .
I posted about this earlier (Hitachi CT7883) with the original Video Brain
Remote Transmitter CLU-600PR which broke down over time. The Hitachi VCR
remote control, however, could still control the television perfectly!

But * after * trying an RCA universal remote, the television stopped
responding entirely to even the good remote control. Now I have obtained a
factory remote replacement as per Hitachi's tech support and even this can
not control the television set. The TV stopped responding to remote
controls.

I'm quite certain that the programming efforts of the universal remote put
the TV into a bad state. If I can clear the nonvolatile memory somehow,
this should fix things. But even leaving the TV unplugged had no success.

Any ideas? Is there anything else I can do, short of calling in a repair
person to look at a 13 year old TV set?

--
Jem Berkes
http://www.sysdesign.ca/

If you can't get any help here try posting at
http://www.remotecentral.com/cgi-bin...emote/list.cgi

Perion

On Sun, 24 Oct 2004 08:17:18 GMT, Jem Berkes wrote:

I posted about this earlier (Hitachi CT7883) with the original Video Brain
Remote Transmitter CLU-600PR which broke down over time. The Hitachi VCR
remote control, however, could still control the television perfectly!

But * after * trying an RCA universal remote, the television stopped
responding entirely to even the good remote control. Now I have obtained a
factory remote replacement as per Hitachi's tech support and even this can
not control the television set. The TV stopped responding to remote
controls.

I'm quite certain that the programming efforts of the universal remote put
the TV into a bad state. If I can clear the nonvolatile memory somehow,
this should fix things. But even leaving the TV unplugged had no success.

Any ideas? Is there anything else I can do, short of calling in a repair
person to look at a 13 year old TV set?

Anything is possible, but I can't understand how the use of a remote
control can affect the TV in this way. A much more likely suspect is
that someone has at some time cleaned the screen by spraying it
directly rather than spraying the cleaning cloth, and this is just a
matter of coincidental timing.

Tom

Failure in the IR Pickup circuit, or anything between it and the MPU
inclusive of stuck or corroded tac switches. Due to the age even leaky
diodes or other components going bad will affect these operations.
Start by checking the operating potentials at the IR Pickup and
confirm indeed it is picking up and transferring the signals from the
remote. If so then trace that signal all the way to the MPU. Severe
clipping or loss of the Control Signals from the IR Pickup while in
route to the MPU will affect its functions. IMHO it is highly unlikely
that you have changed any data parameters when using the universal
remote that will result in this symptom.

OK, I'll try to measure the signals to see where the data is getting lost.
But I seriously doubt that the pickup circuit stopped working due to
physical components failing!

The failure to respond to IR commands happened * suddenly * and correlated
directly with use of a foreign remote control. It was working perfectly,
then universal remote was attempted, now 1 minute later and the TV no
longer responds to IR commands.

Unless there was a digitally triggered component failure - which is
possible but I think highly unlikely, I think that the seized up control
circuitry is not physically broken but is reading bad state information
from memory.

If there was an easy way to clear that memory, I would attempt that first.

--
Jem Berkes
http://www.sysdesign.ca/

A "stuck" front button, or a "locked up" T.V.,
could cause this! Unplug the unit for a couple
of minutes! Also, it may have just coincidently
broke..the T.V. that is! If it's failed, & it's not
the above...try high voltage capacitors! Rono.

I have tried leaving the TV unplugged over night. No such luck. The manual
controls on the front of the TV still work.

Of course it is possibe the TV encountered a hardware failure at the exact
same time the universal remote was attempted. But considering that this
'coincidence' would have occurred in a 1 minute window within 13 years of
operation, my guts tell me that the universal remote played a role.

Either that or I just experienced a one-in-a-"7 million" coincidence :)

--
Jem Berkes
http://www.sysdesign.ca/

Subject: TV stopped responding after RCA universal remote
From: Jem Berkes
Date: 10/24/04 11:48 PM Eastern



Either that or I just experienced a one-in-a-"7 million" coincidence :)



Or you need to turn off that bank of compact fluorescent lights you've been
using while trying remotes!!!
:o)

John

Did you say 13 years old? I'm a little surprised no one has mentioned
looking at the circuit board for a bad solder connection. I'm assuming
after 13 years of operation, the components must have expanded and
contracted a few times.

I don't think the remote is the problem, nor do I think it's the cause
of the problem.

The first thing I'd do is check for cold solder (definitions of "cold
solder" may vary but we all know what I'm talking about...right?)
anywhere in the IR circuitry....and pretty much anywhere at all since
you have the unit open already.

Take note of where you find problems with the connections of the
components to the circuit board and do a quick test of any active
components to see if they've shorted or if they're open.

Take good long look at the circuit board to see if there is anything
visibly wrong (i.e. bulging capacitors, burnt resistors, cracked
transsistors, diodes, ICs, water damage, etc etc etc.).

After that, I'd say it's safe to start looking into the circuitry for
the problem. If these steps are not taken first, you may very lilkely
be doing alot of work for nothing.

I hope this helps,

Dan


Jem Berkes wrote in message
...
I posted about this earlier (Hitachi CT7883) with the original Video Brain
Remote Transmitter CLU-600PR which broke down over time. The Hitachi VCR
remote control, however, could still control the television perfectly!

But * after * trying an RCA universal remote, the television stopped
responding entirely to even the good remote control. Now I have obtained a
factory remote replacement as per Hitachi's tech support and even this can
not control the television set. The TV stopped responding to remote
controls.

I'm quite certain that the programming efforts of the universal remote put
the TV into a bad state. If I can clear the nonvolatile memory somehow,
this should fix things. But even leaving the TV unplugged had no success.

Any ideas? Is there anything else I can do, short of calling in a repair
person to look at a 13 year old TV set?