First let me introduce myself, my friends call me Iron and that is my name on the
Pro a/c and refrigeration blogs that I am a member of, I am a Service Manager for a Mechanical contractor.
I have a Philips M) 55PP935217
S) 78339748 rear projection
my blue convergence is off
the red is fine but on the blue, everything lines up except on the top right and bottom left adjustments. the center of the screen is fine and lines up correctly.
If the blue convergence chip was bad I would think that the entire screen would not line up
but I am not an expert.
do you think that the blue chip is bad or perhaps just one of the resistors?
thanks in advance
There is no "blue chip" per se, blue horizontal is on channel 1 of the stk392-120 convergence ic7044, blue vertical is on channel 1 of the stk392-120 convergence ic7045.
For blue H only check 7044 pins 6,7,9 and resistors 3149 and 3150, blue V only check 7045 pins 6,7,9 and resistors 3157 and 3158, but it's best to check soldering on all the pins of both convergence ic's and all the convergence resistors 3149 - 3160, (6R8 = 6.8ohm 1w flameproof).
If you find bad solder joints on the ic's you can try touching them up, but they may have to be replaced, R68's should read 3.4ohm in circuit, look for burned circuit traces if you have burned resistors.
Page 122 of the service manual has the schematic, page 89 more info on H conv.
stk392-120 datasheet:
http://www.techlore.com/download/29321/STK392-120.pdf/
Philips 300 series RPTV service manual:
http://www.techlore.com/download/22580/DPTV305.pdf/
great info, thanks
I am headed to Miami this morning but will follow your instructions when I get back
thanks much for helping me out