Focus after replacing Flyback Trans. JVC

Model is ???? Flyback is Generic or ? Tell us more.

It is model AV-32F703. I am not sure if the tranformer I bought is generic or not, here is a link to the part I bought.

Thanks Chad

QQH0125-001.

Are there two focus controls? If so, one of the will affect the sides more than the other. It's also possible that the old flyback damaged the dynamic focus circuit when it failed. Andy Cuffe

snipped-for-privacy@psu.edu

There are 2 focus knobs.

Yes, 2 focus and a screen adjust on the FB trans

Apprently you have missed rare few old RCA TVs that had 2 H & V focus pots along with one screen. Even RCA does sell newer TVs with this but it is often found in high end type.

JVC using them, Samsung does. Not just in monitors. Gives best overall focus. Some do have dynamic focus circuits as well which actively corrects for the focus error.

Cheers, Wizard

So what should I try to fix this issue?

Yes I have seen a few of the older RCA,s with that added focus block (2 Focus) and even Mits and like you say high end sets but to date I have not seen a JVC 32 with it. Just making sure he has the 2 Focus Pots and Screen as well...

kip

Dynamic focus? (that extra ring of wire you thought didn't do anything and its associated circuitry)

The white wire, I soldered that back in place!?

I'm sure there is an official procedure, but this always works for me.

First, figure out which control is which. One will appear affect the overall focus. This is the vertical focus control.

The other will mostly affect the width of vertical lines and has the most effect at the left and right edges of the screen. This is the horizontal focus.

Start with both controls near the middle of their range. You need to display something with sharp vertical lines at the edges and sharp horizontal lines in the center (a cross hatch is best).

First, adjust the horizontal focus for the sharpest vertical lines at the edges. Ignore the thickness of the scan lines for now, just make the vertical lines are as thin as possible.

Next, adjust the vertical focus for the thinnest horizontal scan lines in the dead center of the screen. Alternate between the two several times because they interact with each other heavily.

If you don't have any way to display a cross hatch, you can use a computer if it has a TV output, or even the on screen menus of a VCR. Andy Cuffe

snipped-for-privacy@psu.edu

The old Zeniths with dual focus had a procedure of putting a crosshatch pattern on the screen, adjust one focus for the thinnest vertical ine, the other for the thinnest horiz line. This works for me on all dual focus sets. Once you have a crosshatch pattern on the screen it is easy to see which control effects horiz and which effects vertical. From there you have to go back and forth between the two a few times to eventually get both at optimum. I don't like um, but part of the business.

Here is another thing, the tranformer has a black and red wire coming off it that connects to the board off the CRT, it is labled A and B - I did not see how those came off. I put them back as Black -A and Red B, would this effect anything?

Duh ! Obviously... yes.

-- Best Regards, Daniel Sofie Electronics Supply & Repair

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

So does anyone know if the red is A and the Black is B, or just the opposite?