new flyback

[ctc17]

Hmmmm, I have never seen a set with proper boost, good picture and full width that had low high voltage. What was the complaint with performance again?

[timmy]

Originally Posted by ctc17

Hmmmm, I have never seen a set with proper boost, good picture and full width that had low high voltage. What was the complaint with performance again?

the lack of height and width and the lines on the left that are distorted. i used the horiz centering to make up the width but i still understood the set had problems. just adjusted what i can to see how the set worked in the beginning. the source voltage 1010v is 1200v and i think the boost 570v is around 800v i dont remember exactly.

[timmy]

hey guys i know i have been a thorn in the sides of some but is there anyone that can lead me in the right direction to get full hv back in this motorola set. i do have limited knowledge of this old stuff but i am trying. after a new flyback i still have low hv and i took each wire one by one off the flyback except the hot cap wire and the hv lead from the damper and there is no change. when i power up the hv will go to 16kv and within seconds it drops to around 10kv and the cathode current is still up around 250ma where it should be at 210ma. i have eliminated the wires to and from the fly and in the circuit , removed the hv reg tube, tried another horiz oscillator tube and checked resistors around that tube socket, and went ahead and got a new yoke really because the old one is falling apart anyway, dried up plastic, and the yoke made no difference either. what could be left to raise the cathode current and starve it for hv. being everything i disconnected it dont leave much more but maybe the drive to the hot for the fly if this is possible, would the cathode current raise up and not have enough hv if the drive were to slow or just not at the right frequency because of a bad cap,and where would i look for this cap if it were a possibility.............

[timmy]

well this is it , 12kv only and cant get anymore from it. and even if my hv probe is off alittle it still has low hv. now the vert is having a hard time locking in.

[ctc17]

Im fighting a rca that has a simular issue can only get 20kv and thats not enough for the regulator to take effect so the picture is unstable.

Ill tell you this...there is NO WAY that picture is comming from 12kv. NO WAY!! If you only had 12kv the focus and boost voltage would be so low and the thing would be blooming so bad it would be a smeared out blured mess.
That is a good picture.

[timmy]

this is what i have been saying that it gives a good picture but the g1 master is only up a quarter way because it will bloom and wash out to nothing as well as the contrast if turned cw and the g2 adjustments have to be on the low ccw side. anything that effects the hv has to be set low and im sure this was not like this from the factory in 1966.it wound out being the 4.7k resistor in the yoke that was giving the lines on the left side of the picture. if i were to raise the g1 master it would bloom and pull to the right and leave the left side 3 inches gone. so it still has low hv and why i just dont know and maybe my hv probe is not right but if it were, well it would show how low it really is. now i have to figure out why the vert wont lock.

[sharejutt]

Convergence problem on an rca 52 inch tv?