Subject: RCA EPROM QUESTION?
From: (daveem Dave M)
Date: 7/9/03 1:31 PM Eastern Daylight Time
Message-id:

Hi all,
I was just wondering if any one here knows the general difference
between the various Eproms RCA and GE use in their television sets? I
know a tech who regularly replaces Eproms with RCA part numbers that
don't match the original part, and he said that some of the Eprom chips
are interchangeable, but I hate to gamble on this. Any help would be
appreciated. Thanks,
Dave


The basic rule is that if the new eeprom comes from a chassis that uses the
exact same uPc as is in the original chassis, the eeprom will work normally.
The only difference will be in the features\options available in the menus. If
you sub in an eeprom from a high end chassis that uses the same uPc as the
original, the TV will work and may offer upgraded features such as channel
labeling, speaker on\off, etc. If you sub backwards, the TV may be missing
features such as PIP, A\V inputs, stereo, or even experience geometry problems.

John Del
Wolcott, CT

"Nothing is so opportune for tyrants as a people tired of its liberty."
Alan Keyes

(remove S for email reply)

RCA EPROM QUESTION?
Thanks for all the info. I'm not sure how one can down load the settings
from the last chip, but that could sure come in handy. Those tuner
settings take forever to align. but some people claim you can just
follow their pre-determined settings and it will be close enough, or buy
a pre-programed Eprom. My friend claims he just put them all at 31 and
that does the job.
Dave



Group: sci.electronics.repair Date: Wed, Jul 9, 2003, 10:31am From:
(daveem=A0Dave=A0M)
Hi all,
I was just wondering if any one here knows the general difference
between the various Eproms RCA and GE use in their television sets? I
know a tech who regularly replaces Eproms with RCA part numbers that
don't match the original part, and he said that some of the Eprom chips
are interchangeable, but I hate to gamble on this. Any help would be
appreciated. Thanks,
Dave

Sounds like he is not really fixing the sets or knows what he is doing.
Full tuner alignment can take as little as 15 minutes and is easy to do.
With the Chipper Checker interface and a custom outboard socket for the
eeprom the old eeprom can typically be read and the tuner values read out.
HOWEVER, any time the tuner grounds were enough to cause an eeprom in the
first place, ALL the eeprom data values are suspect and I usually just do a
full chassis alignment in way for best tv set performance. Takes about 45
minutes MAXIMUM to do all the alignments.

David

daveem Dave M wrote in message
...

RCA EPROM QUESTION?
Thanks for all the info. I'm not sure how one can down load the settings
from the last chip, but that could sure come in handy. Those tuner
settings take forever to align. but some people claim you can just
follow their pre-determined settings and it will be close enough, or buy
a pre-programed Eprom. My friend claims he just put them all at 31 and
that does the job.
Dave



Group: sci.electronics.repair Date: Wed, Jul 9, 2003, 10:31am From:
(daveem Dave M)
Hi all,
I was just wondering if any one here knows the general difference
between the various Eproms RCA and GE use in their television sets? I
know a tech who regularly replaces Eproms with RCA part numbers that
don't match the original part, and he said that some of the Eprom chips
are interchangeable, but I hate to gamble on this. Any help would be
appreciated. Thanks,
Dave

So which bytes were corrupt, how did you identify them, and what data did
you use to replace the corrupt data? The most common problem with many RCA
EEPROMS is the audio mute problem. Which byte is bad?

Leonard

"Wildcard" wrote in message
...

Seems like a lot of work for just a couple corrupted
bytes in the eeprom. In most of the eeprom related
problems I have found none of the eeprom's were
actually bad. The just had corrupted bytes in
the sectors that the micro won't write.

I pull the ic. Read it in a simple eeprom programmer.
fix the corrupted bytes in hex editor. then rewrite
the eeprom. Then it's just a simple matter of
installing a socket and reinstall the ic.

Works almost every time. As far as the orginal startup
data. As I ordered ic's orginally to fix these problems
I read each one and saved by part number. That gave me
my needed orginal settings. The only time I order a
rca orginal eeprom is when I don't have one on file.

Built the programmer out of bits and pieces sitting
around. Got the software off the net.

Seems like a lot of work for just a couple corrupted
bytes in the eeprom. In most of the eeprom related
problems I have found none of the eeprom's were
actually bad. The just had corrupted bytes in
the sectors that the micro won't write.

I pull the ic. Read it in a simple eeprom programmer.
fix the corrupted bytes in hex editor. then rewrite
the eeprom. Then it's just a simple matter of
installing a socket and reinstall the ic.

Works almost every time. As far as the orginal startup
data. As I ordered ic's orginally to fix these problems
I read each one and saved by part number. That gave me
my needed orginal settings. The only time I order a
rca orginal eeprom is when I don't have one on file.

Built the programmer out of bits and pieces sitting
around. Got the software off the net.