magnavox Mod RL8570,chas PTV380
 

HI ALL
Magnvox PTV380 , can not get Vertical center. Have no Schmatic working
from bits and pieces of other s Schmatic's
I'v changed the Vert IC ,checked voltages around the vert IC,all look
good .
Have +20 ,-20 at conv PRW Supply, +12,-12 at the conv BD.
The more checks and Adj I make , Looks more like some thing wrong in
Vert IC Section . missing bottom portion of sweep with a trapazode
effect.maybe I should try another Vert IC .
Just checked D552 off pin 1 of Vert IC. Is this doide paralleled with
a resistor .getting a bad read on this .
If Anybody has seen this problem or has any ideas I would sure
appreciate
It .Anybody have a schmatic for this PTV380
Thanks Bob Searcy

magnavox Mod RL8570,chas PTV380
 

For test purposes you can safely remove D552 and see if you get your full
deflection.
There should be 10 k across D552
There should be around 14 volts at pin 1 of IC550.

Hope this helps,
Bill Jr




"Bob Searcy" wrote in message
om...
HI ALL
Magnvox PTV380 , can not get Vertical center. Have no Schmatic working
from bits and pieces of other s Schmatic's
I'v changed the Vert IC ,checked voltages around the vert IC,all look
good .
Have +20 ,-20 at conv PRW Supply, +12,-12 at the conv BD.
The more checks and Adj I make , Looks more like some thing wrong in
Vert IC Section . missing bottom portion of sweep with a trapazode
effect.maybe I should try another Vert IC .
Just checked D552 off pin 1 of Vert IC. Is this doide paralleled with
a resistor .getting a bad read on this .
If Anybody has seen this problem or has any ideas I would sure
appreciate
It .Anybody have a schmatic for this PTV380
Thanks Bob Searcy

magnavox Mod RL8570,chas PTV380
 

For test purposes you can safely remove D552 and see if you get your full
deflection.
There should be 10 k across D552
There should be around 14 volts at pin 1 of IC550.

Hope this helps,
Bill Jr




"Bob Searcy" wrote in message
om...
HI ALL
Magnvox PTV380 , can not get Vertical center. Have no Schmatic working
from bits and pieces of other s Schmatic's
I'v changed the Vert IC ,checked voltages around the vert IC,all look
good .
Have +20 ,-20 at conv PRW Supply, +12,-12 at the conv BD.
The more checks and Adj I make , Looks more like some thing wrong in
Vert IC Section . missing bottom portion of sweep with a trapazode
effect.maybe I should try another Vert IC .
Just checked D552 off pin 1 of Vert IC. Is this doide paralleled with
a resistor .getting a bad read on this .
If Anybody has seen this problem or has any ideas I would sure
appreciate
It .Anybody have a schmatic for this PTV380
Thanks Bob Searcy

magnavox Mod RL8570,chas PTV380
 

"Bill Jr" wrote in message . com...
For test purposes you can safely remove D552 and see if you get your full
deflection.
There should be 10 k across D552
There should be around 14 volts at pin 1 of IC550.

Hope this helps,
Bill Jr

Thank You Bill for helping Me .
I removed the diode D552, no luck.
I THINK IT COULD BE A CAP ,OR OPEN RESISTOR IN THE RETURN LINE .
IF YOU WOULD GIVE ME THE NUMBER DESIGNATION OF THE CAPS ,MAYBE THAT WILL DO IT
BOB SEARCY PS I ALSO REPLACED THE IC


"Bob Searcy" wrote in message
om...
HI ALL
Magnvox PTV380 , can not get Vertical center. Have no Schmatic working
from bits and pieces of other s Schmatic's
I'v changed the Vert IC ,checked voltages around the vert IC,all look
good .
Have +20 ,-20 at conv PRW Supply, +12,-12 at the conv BD.
The more checks and Adj I make , Looks more like some thing wrong in
Vert IC Section . missing bottom portion of sweep with a trapazode
effect.maybe I should try another Vert IC .
Just checked D552 off pin 1 of Vert IC. Is this doide paralleled with
a resistor .getting a bad read on this .
If Anybody has seen this problem or has any ideas I would sure
appreciate
It .Anybody have a schmatic for this PTV380
Thanks Bob Searcy

magnavox Mod RL8570,chas PTV380
 

"Bill Jr" wrote in message . com...
For test purposes you can safely remove D552 and see if you get your full
deflection.
There should be 10 k across D552
There should be around 14 volts at pin 1 of IC550.

Hope this helps,
Bill Jr

Thank You Bill for helping Me .
I removed the diode D552, no luck.
I THINK IT COULD BE A CAP ,OR OPEN RESISTOR IN THE RETURN LINE .
IF YOU WOULD GIVE ME THE NUMBER DESIGNATION OF THE CAPS ,MAYBE THAT WILL DO IT
BOB SEARCY PS I ALSO REPLACED THE IC


"Bob Searcy" wrote in message
om...
HI ALL
Magnvox PTV380 , can not get Vertical center. Have no Schmatic working
from bits and pieces of other s Schmatic's
I'v changed the Vert IC ,checked voltages around the vert IC,all look
good .
Have +20 ,-20 at conv PRW Supply, +12,-12 at the conv BD.
The more checks and Adj I make , Looks more like some thing wrong in
Vert IC Section . missing bottom portion of sweep with a trapazode
effect.maybe I should try another Vert IC .
Just checked D552 off pin 1 of Vert IC. Is this doide paralleled with
a resistor .getting a bad read on this .
If Anybody has seen this problem or has any ideas I would sure
appreciate
It .Anybody have a schmatic for this PTV380
Thanks Bob Searcy