Emerson 609 projection TV

[Phil Nelson]

I have been puttering along with this set in recent months. After recoating two mirrors and spending more time with the electronics, it makes a better semblance of a picture:



As you probably noticed by Sam's stretched head in that pic, the horizontal linearity is pretty awful. This test pattern shows that the vertical linearity is also poor:



I have gone back through the sweep circuits, replacing a handful of components, without finding an obvious cause for bad linearity in both directions.

If you go back to page 1 of this thread, you'll see that I removed a one-capacitor modification made by a previous owner: that cap paralleled the width coil and the idea seems to have been to affect the width.

Now I'm tempted to reinstall a cap in that position and see what happens . . . .

If I can't solve the linearity problem with the electronics, I'm back to fiddling with the optics, which I honestly don't understand very well. One idea that occurred to me is that maybe I reinstalled the recoated spherical mirror off-kilter. Testing that theory would be difficult, since that mirror's mounting screws are not intended as adjusters. There's a lot of elbow room for the screws in those holes and absolutely no guide as to what is the correct position. In the factory, I supose they set this mirror using a jig.

I've been updating my restoration article as I go along. You can read more details and see more pics at: https://antiqueradio.org/Emerson609P...Television.htm .

Regards,

Phil Nelson
Phil's Old Radios
https://antiqueradio.org/index.html

[Phil Nelson]

Originally Posted by Phil Nelson

If you go back to page 1 of this thread, you'll see that I removed a one-capacitor modification made by a previous owner: that cap paralleled the width coil and the idea seems to have been to affect the width. Now I'm tempted to reinstall a cap in that position and see what happens . . . .

Well, putting a cap (something from .33 to .66) across the width coil increases the width and lets you adjust for somewhat better horizontal linearity.

For comparison, here's the previous test pattern:



And here's today's pattern:



Not a great improvement, but something. It still feels like the horizontal circuits are just "off" in general -- the adjusters for horiz drive, horiz linearity, and horiz size are all maxed in one direction.

The worst horizontal linearity is not at the far left edge, but in a band that starts maybe 20% in from the left edge. If you squeezed that band horizontally, you'd have a pretty watchable picture.

Strangely, now it's easier to adjust for better vertical linearity.

Phil Nelson
Phil's Old Radios
https://antiqueradio.org/index.html

[kvflyer]

Have you ruled out optics and are now focused (pun intended) on the sweep circuits? I know that you were reluctant to view the face of the actual CRT.