GE 25GH350 CTC177AJ2 Snowy channals above 50.

S

Suburban

Guest
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
 
You will need Chipper Checker and Multi
Channel Geny to do a complete alighment.
First check your own work and make sure no
solder bridges.

kip

--
"Watch the return E-Mail addy its false"
"Suburban" <suburban@columbus.rr.com> wrote in message
news:6KPfc.3715$nv3.2179@fe1.columbus.rr.com...
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and
above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
Click to expand...
 
Suburban:
Once you replaced the EPROM you lost all of the tuner alignment parameters
in all of the televisions unless you read and save the data from each
television's old EPROM.
The first order of business after verifying your rework is to perform a 125
channel tuner alignment. A chipper checker and 125 channel television
signal generator would be most helpful at this point.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


"Suburban" <suburban@columbus.rr.com> wrote in message
news:6KPfc.3715$nv3.2179@fe1.columbus.rr.com...
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and
above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
Click to expand...
 
Did you do the full chassis/eeprom alignment per the service manual?
Which includes the 125 channel cable tuner alignments!!!!! You need a
125 channel calibrated signal generator with adjustable output in
order to do the alignment, along with an RCA remote control. The
TAG001 tuner generator Thomson use to sell worked great because you
could change the tv and generator channel at the same time.

David

Suburban <suburban@columbus.rr.com> wrote in message news:<6KPfc.3715$nv3.2179@fe1.columbus.rr.com>...
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
Click to expand...
 
Try this:

Q7404 PNP V/U Bandswitch Affects Cable Channels 51-Higher RCA # 215496
Device Marking 3F SMT Type BC857B (NTE2409)

Robert McPherson
rm502@bellsouth.net

dkuhajda@locl.net (David) wrote in message news:<68f82f5b.0404161326.6c9fbb01@posting.google.com>...
Did you do the full chassis/eeprom alignment per the service manual?
Which includes the 125 channel cable tuner alignments!!!!! You need a
125 channel calibrated signal generator with adjustable output in
order to do the alignment, along with an RCA remote control. The
TAG001 tuner generator Thomson use to sell worked great because you
could change the tv and generator channel at the same time.

David

Suburban <suburban@columbus.rr.com> wrote in message news:<6KPfc.3715$nv3.2179@fe1.columbus.rr.com>...
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
Click to expand...
 
Foregt to mention this transistor in my first suggestion - It can also
cause snowy channels above 51:
Q7101 UHF RF AMP MOSFET RCA # 200566

Robert McPherson
rm502@bellsouth.net

dkuhajda@locl.net (David) wrote in message news:<68f82f5b.0404161326.6c9fbb01@posting.google.com>...
Did you do the full chassis/eeprom alignment per the service manual?
Which includes the 125 channel cable tuner alignments!!!!! You need a
125 channel calibrated signal generator with adjustable output in
order to do the alignment, along with an RCA remote control. The
TAG001 tuner generator Thomson use to sell worked great because you
could change the tv and generator channel at the same time.

David

Suburban <suburban@columbus.rr.com> wrote in message news:<6KPfc.3715$nv3.2179@fe1.columbus.rr.com>...
This is a these are motel sets. I got 3 in, I resoldered all known
connections and replace the EPROM's, and all 3 Osc\mixer ICs.
The 2 in question came in for no channels from 2 to 50, after replacing
the parts and soldering, now the two have snowy pictures from 51 and above.

I replaced U3201, Q7403, and U7301.
T checked R7121.

Any help I will thank you for in advance.

Ken Marshall
Suburban Electronics
PO Box 251
Hilliard, Oh 43026-0251
Click to expand...
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top