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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Feb Thu 01, 2018 2:48 am 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1729
Location: Monroe, NC 28112 USA
I have the FADA 880 that seems to be a clone... I've never had the guts to attempt a functional repair.

Robert


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Mar Sat 03, 2018 11:52 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1299
Location: Phoenix, Arizona
Without reading back through the posts (which I should) I have worked on a bunch of TV sets using the Protelgram projection system.

I have a Scott 6T11 I watch regularly and my test is to be able to see the scan lines in focus. With the 6T11 you can slide the screen back and forth and if you push it back just a little you get a double image (use a crosshatch slide in a BK scanner) which is useful in setting the over-all focus. You match up the double image and keep sliding it forward until it aligns perfectly.

I did collect the 609's but they have moved on.

All of the mirrors are front surface and I have tried many, and none seem to reflect as good as the original. The biggest problem is the big mirror on the underside of the lid. Not any crappy old mirror will work (trust me on this). I thought of getting a mirror out of a three tube projection set and trying that.

The mirrors inside the optical box are just as fragile, but usually they don't get touched.

Stand in the shower, naked and use hair shampoo and rinse the mirror until the water runs off and carefully pat it dry, and don't scrub it.

The lens on top of the Schmidt optical box is chosen for the distance to the screen. This is some kind of plastic gel. If you have the wrong lens you will never get it in focus, or it will not be in even focus.

Another issue is if you crank up the brightness or contrast too much you will push the beam current too high and the picture will blur out of focus due to lack of HV.

I run my 6t11 just below the point of blurring.

The picture will not be quite as bright as grandpa's 21 inch Zenith but it will be very watchable

The High Voltage box needs to put out at least 25,000 volts and more is better. It needs to be in its regulation range if you want a nice bright picture. Some of the later HV box's regulate at 27,000 volts. The frequency of the oscillator in the HV box needs to be Exactly 1000 Cycles (1000 Hz for Millennial's), Exactly, no fudge.

KEEP IN MIND the 25,000 volts HV will make X-rays from that little 3" CRT

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Mar Wed 07, 2018 5:36 pm 
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Joined: Oct Thu 23, 2014 5:15 pm
Posts: 95
there is an identical set on Craigslist Long Island N.Y. for $150.00 that looks very good. Owner says it work

https://newyork.craigslist.org/que/atq/ ... 06699.html Local pick up only. Two hour drive each way for me. I'll never convince my wife that it's worth it. Any ideas?


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Mar Wed 07, 2018 9:05 pm 
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Location: Woodinville, WA USA
That cabinet looks nice --maybe a little better than mine. A price of $150 is not unreasonable. I paid about that (maybe $175?) for my 609.

As TV projects go, an Emerson 609 is difficult. The electronics are not terribly unusual. I got them working nicely on my set without much effort beyond the standard replacement of capacitors, cleaning controls & tube pins and sockets, etc., etc.

The optics add another layer of complexity, after you have done everything normally needed to make a non-projection TV work well. I have resilvered two mirrors in my 609. I brought my emptied cabinet to a refinisher to have it redone, but he had arthroscopic surgery and I had to haul the un-refinished cabinet back home. I could temporarily reinstall everything in the cabinet, to see whether I can re-align the optics with my two new mirrors in place, but putting it all back together is a significant chore, so I'm debating whether to do it now and then pull it all back apart when my refinisher guy is well, or just wait. You can read more about all that in my 609 article at https://antiqueradio.org/Emerson609Proj ... vision.htm .

If you go to see an Emerson 609, I'd try to get a peek at the mirrors. You can see the internal 45-degree plane mirror (much of it) by shining a flashlight down through the lens on top of the Protelgram box. You can see the big (final) mirror by poking your head into the back of the cabinet and shining a light upward. (The display hood must be raised to make that mirror visible.) These mirrors can be recoated, but it's not cheap. I have spent more on that than I paid for the TV in the first place.

This seller states that it "works," but that might only mean that the tubes lit up when they plugged it in. It would be a minor miracle of an unrestored 609 worked well enough to display a coherent picture.

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


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Mar Wed 07, 2018 10:10 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1299
Location: Phoenix, Arizona
As many of these as I have restored there should be some working ones kicking around.

My first one was in kit form and I had to make some of the wood panels to get it together,

I also had to scab together a High Voltage supply until I found some on ebay.

You can always hide a set-top converter inside the cabinet and hit it with the remote through the screen and top mirror.

As I recall this is a "Hot Chassis" set even though it has a transformer.

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Mar Thu 08, 2018 2:18 pm 
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Joined: Oct Thu 23, 2014 5:15 pm
Posts: 95
Thank you Phil and Jim!

Interesting link on your restoration Phil! Sounds like a very complex set, probably a bit beyond my abilities, so I think I will have to pass on this one. Hope you get the cabinet done soon Phil. Keep us posted!


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Thu 05, 2018 6:16 am 
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After much cussing & fussing, I wrangled all the 609 parts & pieces back together, and tried the whole TV for the first time since recoating the mirrors. I was fearful that it wouldn't focus at all, but I'm getting halfway-decent focus after only a couple of preliminary adjustments:

Image

The focus in person is somewhat better than in this snapshot.

That concludes the good news for today. When I put a pattern on it, you can see that the horizontal and vertical linearity both suck. This is after adjusting the width, height, and both linearities as best I could using the electronic controls:

Image

Tomorrow, I'll go back to the manual and work through all of the optical adjustments. In addition to an "optical focus" mechanical adjuster for the center of the screen, the Protelgram unit has "horizontal focus" and "vertical focus" mechanical adjusters, which affect the sides and top/bottom areas. Once those three mechanical focus adjusters are set properly, you can rely on the two (yes, two) electronic focus controls.

There's more work to do, but I'm encouraged to get a semi-watchable image out of this beast at long last.

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


Last edited by philsoldradios on Apr Sun 22, 2018 6:54 am, edited 1 time in total.

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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Thu 05, 2018 1:57 pm 
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Location: Waxahachie Texas
Good for you!

_________________
Crist


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Fri 06, 2018 12:05 am 
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Posts: 1299
Location: Phoenix, Arizona
Looking good.

My goal was to be able to see scan-lines across the screen.

It is not as simple as it looks to get it aligned.

I found it eisier to tweak in with a full crosshatch.

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sat 07, 2018 3:00 am 
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Ha ha -- I don't think I'll be counting scan lines on this one any time soon :)

I use a crosshatch pattern a lot, but the circle and cross show you at a glance just how bad the linearity is in both directions.

Still haven't gotten around to messing with the remaining optical adjustments, but it's on my to-do list, I promise! I'm wondering if some of the non-linearity is owing to bad physical alignment in the optics. I can't remember any other TV where linearity was so far off in BOTH directions . . . .

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


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sat 07, 2018 7:53 am 
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Joined: May Sun 07, 2017 11:35 am
Posts: 384
Maybe you should start with getting the geometry correct directly on the face of the CRT, brightness reduced of course.....


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sat 07, 2018 4:10 pm 
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Joined: Jun Mon 24, 2013 3:00 pm
Posts: 1131
Location: Champaign IL 61822
Another suggestion: make a transparency, or several, of a crosshatch, and tape them
to the front of the TV screen. Then shine lights BACK from it to the CRT face. IF you can
somehow see the CRT face, you can tweek with the TV turned off,

Of course, seeing the CRT may be impossible so this may be a useless suggestion.


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sat 07, 2018 6:19 pm 
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Good ideas, but you can't directly view the CRT face, except at an extreme angle. It's mounted in a sealed optical box, with its face perpendicular to the floor.

Image

When I had the chassis on the bench, here's what you could see by peeking down into the optical box, through the top corrector lens:

Image

From that angled view, you can roughly judge the degree of focus at the CRT face, but you can't see the whole image in a way that's useful for linearity adjustments. Not to mention that all of the linearity adjusters are on the opposite side of the cabinet, so you would have to scuttle back and forth between the front of the cabinet where the adjusters are located, and the rear where the optical box is mounted, repeatedly. (In other words, you can't watch the image change while you turn an adjuster.) And don't forget -- the CRT uses a nominal 25KV, so you don't want to hold your head inches away from it for long periods, unless you enjoy toasting your brain with X-rays.

Regards,

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


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sun 08, 2018 1:33 am 
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Oh. I forgot it's a Schmidt optics system. D'oh!

For the vertical linearity, what about scoping the yoke current by putting about 0.1 ohm in series? Is that practical? You should see a nice straight diagonal line.

For the horizontal, normally best linearity is pretty close to minimum driver current. Cathode current thru the driver?

I guess the aim is to get it as close as possible electrically before you adjust the optics.

How old are you? Got kids? No? You can get sheet lead flashing (to make underpants) from most hardware stores.....


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Mon 09, 2018 4:32 pm 
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Joined: Jan Thu 01, 1970 1:00 am
Posts: 1299
Location: Phoenix, Arizona
As the high voltage used on these projection sets is well over 25,000 volts I sugest keeping some distance from the CRT even when the optical box is buttoned up due to X-Ray damage to your eye balls.

That said when I was into perfecting my Scott 6T11 which uses the same Protelgram system I had several Aspherical corrector lenses (the lens on top of the optical box) and the lens that was with my Scott (which was sent to me in kit form) would not make even focus on the screen.

The lens has numbers stamped which is suposed to tell you which lens works with which throw distance.

At the time I had a bunch of optical parts and several lenses and had two of the Emerson 609's in operation.

The Scott has a shorter throw than the 609, To focus it up I can remove the stop and slide the screen forward about a 1/2 inch and then with a cross hatch I get a double image on the screen.

I can match up the double image as I slide the screen into position and get even focus. With the Scott you can see the screen and reach the optical afjustments.

The angle the screen stop is set for can make your focus job difficult. As I recall my 609's had some shim washers under the optical box to put a slight tip in it.

You can obtain almost perfect focus with a great deal of tweaking.

My 6T11 has developed a bad linearity problem which I fixed to a degree by replacing the Vertical output tube with something like a 6L6, I guess its time to re-cap.

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Mon 09, 2018 10:32 pm 
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After more fiddling, I think I've gotten the optical adjustments as good as I'm likely to get 'em. The biggest problem remaining is linearity (in both directions), so I'll work on the electronics next.

That Scott sounds easier to work on than this Emerson. On this Protelgram, the big box has screw tilt adjusters between the bottom mounting plate and the box. I haven't messed with those, but it looks like it may have a slight back-to-front tilt.

My kids are thirty-somethings, so lead pants aren't an issue. A lead ski mask might be more useful, since your head gets pretty close to the box when you crouch down to play with the optical adjusters.

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


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Sat 21, 2018 9:32 pm 
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I spent some time checking out the sweep circuits (horizontal & vertical) and sync circuits, replacing a couple of mica caps and a few resistors. I also swapped all the horizontal tubes (including damper) out of superstition, with no improvement. No smoking guns, in short, and the bad linearity (both horizontal & vertical) is still just as bad:

Image

I wonder if I reinstalled the spherical mirror a bit off-center? I'm not good at these thought experiments, but I believe that could account for the stretching in two directions that goes beyond the ability of the electrical adjustments to compensate.

The spherical mirror bolts to the rear of the big optical box with three screws, which have quite a bit of leeway in their large mounting holes.

Image

Image

I guess the intent was that the mirror would be installed once at the factory -- probably with the aid of a jig -- and then never touched again. When reinstalling the mirror, I tried to center these screws in their holes:

Image

That was a crude method, as you can see. Unfortunately, with all three chassis in place, there's no way to slightly loosen these mounting bolts and shift the mirror while watching the screen. I'll need to pull the whole thing apart, make a blind adjustment to the mirror mounts, put it all back together, and see what gives.

Grrr.

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


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Mon 23, 2018 6:13 pm 
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Posts: 1299
Location: Phoenix, Arizona
Phil

When I look at your picture, the guy on the left looks unlinear and stretched which I would assume to be deflection related.

It would be interesting to see a cross-hatch on the screen.

Since the deflection system for Protelgram works with the RCA 630 circuit and both the Emerson and my Scott use about the same design, it should be easy to get it linear.

In the scott I can slide the screen a little forward, or back and a well focused cross-hatch turns into double lines which makes ti easier to set the optical tweakers.
I wonder if the overall focus knob could yield the same result.

The Aspherical corrector has big mounting holes and as I recall it had ro be positioned carefully.

When I had my Scott at its best, I can see the scan lines anywhere on the screen. I would not say perfectly and evenly focused. As I recall the canter and the outer edges are good and a ring atound the center area was ever so slightl softer but the lines are visible.

Another good thing with the scott is that you can slide the entire cabinet forward on your table and all the controls are accessable from the bottom front.

My Scott has a vertical linearity issue which I have been too lazy to dig into.

I also tend to run brightness and ccontrast up to where I almost overload the HV supply and it goes out of electronic focus.

Your picture brightness look s nice.

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Mon 23, 2018 6:22 pm 
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Location: Phoenix, Arizona
as it is all coming back to me . . . .

I do recall little screws in the feet of the optical box keeping in mind its been 20 years and I sold off my two 609's and kept the scott.

As I recall the front of the cabinet swings open but does the chassis swing out or is it just in the way.

The optical alignment was more persnikity than I expected.

The Scott being a table model has all the chassis stuffed inside the about 2' by 2' cabinet. To work on the receiver chassis the whole thing has to come apart.

You can tweak and view the screen better than the 609 though.

Jim


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 Post subject: Re: Emerson 609 projection TV restoration
PostPosted: Apr Mon 23, 2018 7:12 pm 
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Yes, the left half of the screen is stretched a lot. If you scroll back to the picture of the circle/cross pattern, you can see that the lower half of the screen is also stretched.

I think I have never had a TV where both the horizontal & vertical linearity were so far off. I have gone through those circuits and the electronic adjusters seem to work as you'd expect. That's why I think the linearity problem lies somewhere in the optics.

The aspherical corrector lens on top of the optical box does have adjustment screws, allowing you to rotate the lens and move it up or down. The service manual doesn't explain exactly what the corrector lens does, and it has dire warnings telling you not to touch those adjusters, which "must only be done at the factory."

In addition to the mechanical focus adjusters on the tailpiece assembly, the optical box does have little tilt screws on its base, letting you tilt different sides of the box up or down. I think the box tilt screws are only good for positioning the (already linear) image correctly within the screen opening.

The cabinet front has a door that swings open to expose the hanging chassis. This gives you access to a lot of the chassis underside, but the chassis mounting board blocks access to things around the edges of the chassis -- which includes the sweep circuits.

Image

It's awkward to haul the big chassis in and out, so I have set it behind the cabinet and hooked it up, giving access to the whole chassis for testing. It's still hard to view the screen in a little mirror while adjusting, but nothing about servicing this set is easy!

Image

You can see more photos of the different chassis, etc., in this restoration article, which I'm trying to keep up to date as I fumble along:

https://antiqueradio.org/Emerson609Proj ... vision.htm

Regards,

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


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