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  #16  
Old 05-20-2017, 12:42 PM
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M3-SRT8 M3-SRT8 is offline
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Ahhh! Isn't it fun? Even though we've restored countless old tvs, it still puts a smile on your face when another one springs back from the dead.

Well done. Keep us posted.
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  #17  
Old 06-02-2017, 06:53 PM
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Phil Nelson Phil Nelson is offline
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After recapping & whatnot, the electronics are working pretty well on my Emerson 609. The optical (Norelco Protelgram) portion . . . not so wonderful.



Apart from issues like bad horizontal linearity, which is only an adjustment, the image is not only dim, but unable to focus despite fiddling with the electronic and mechanical focus adjusters.

The 45-degree mirror in the optics box appears to be in bad shape:



Is this the mirror that people send out to be resilvered? If so, where?

I haven't made any attempt to clean it, having read horror stories in the past about people who destroyed projection TV components by inappropriate cleaning.

Phil Nelson
Phil's Old Radios
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  #18  
Old 06-02-2017, 07:45 PM
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Eric H Eric H is online now
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How does the image look directly on the CRT? (I use a mirror to avoid X rays)
I've cleaned these mirrors with soap and water, I even removed the silvering on one and it was really tough to do, that said it will depend on what condition it's in to begin with.
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  #19  
Old 06-02-2017, 08:50 PM
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Phil Nelson Phil Nelson is offline
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The image on the CRT looks good, although it's a little hard to judge when peering in at such an angle. Of course, the smaller the CRT, the sharper things look, too. If I remove the side plates from the optics box, I should be able to inspect the mirrors more closely.

On another note, has anyone ever seen patent documents for the Norelco Protelgram unit? I assume it was patented somewhere, although a quick search of US patents didn't turn up anything.

Phil Nelson
Phil's Old Radios
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  #20  
Old 06-03-2017, 03:43 PM
madlabs madlabs is offline
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Never cleaned a TV mirror but I have cleaned telescope mirrors, which I imagine are affected more by scratches. I use water and soap, a squirt bottle with warm soapy water blasted right on a chunk of smeg will usually get it off. Soak and blast. soak and blast. Garden hose type of pressure washer is good too. Just don't use anything in actual contact with the mirror. That seems to work well with dust/disuse build up.

I have also under duress used a super soft artists paint brush on a mirror that was really gunked. As it turned out the mirror was trashed but I didn't see any scratches from working it GENTLY with the brush.

You can get the mirror redone. If you look for places that make telescope mirrors you can sometimes have them do yours when they are doing another and save some dough. Can take a while that way. I had a mirror I home ground done that way, took two months but was cheap.
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  #21  
Old 06-03-2017, 04:10 PM
pearsonk pearsonk is offline
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Make sure the cardboard/fiber shield is on the crt. From the pics, it looks
like the crt is not as far in as it should be [if memory serves me]. I always
use distilled water on these mirrors to avoid water marks after drying.
I have restored several of these Norelco units and have NOS 3np4s and a resilvered concave mirror........
Currently have a Scott and an Emerson with the Norelco system.
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  #22  
Old 06-17-2017, 09:03 PM
Samuel1981 Samuel1981 is offline
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Update?
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  #23  
Old 06-17-2017, 10:08 PM
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Anyone see this? Perhaps a cheaper way to get your mirror re-done

https://www.youtube.com/watch?v=z8iTQwnDaLg
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  #24  
Old 06-17-2017, 10:51 PM
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Quote:
Originally Posted by batterymaker View Post
Anyone see this? Perhaps a cheaper way to get your mirror re-done

https://www.youtube.com/watch?v=z8iTQwnDaLg
The problem with that is the mirrors in a projection set are on the surface of the Glass, that is behind it.
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  #25  
Old 06-17-2017, 11:16 PM
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Tom Albrecht Tom Albrecht is offline
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I had a mirror resilvered (or more precisely, re-aluminumed) for my Philco projection TV. This outfit does a good job, and won't break the bank. You'll see they show prices right on their website: http://www.spectrum-coatings.com/

The symptom of a bad mirror is poor contrast. Too much light scatters off the rough and dirty spots on the mirrors, putting some light into the dark areas of your picture that doesn't belong there. It will not cause bad focus, so that is a separate problem to be worked out.

Here's a thread on ARF from when I got my mirror recoated: http://www.antiqueradios.com/forums/...524069#p524069

Later I made some further improvements to the set, that resulted in better pictures than I showed in the thread linked above.

Last edited by Tom Albrecht; 06-17-2017 at 11:41 PM.
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  #26  
Old 06-23-2017, 03:16 PM
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Phil Nelson Phil Nelson is offline
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Thanks for the info. We have been away on vacation, but I will probably get a chance to open up the optical box this weekend. I suspect I'll send off the mirror for resilvering.

Apart from that, the TV still needs more work on the focus and horizontal sweep sections.

Regards,

Phil Nelson
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  #27  
Old 06-24-2017, 07:55 PM
Samuel1981 Samuel1981 is offline
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Keep chugging along! This is one of the prettiest of the projection sets.
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  #28  
Old 06-26-2017, 08:05 PM
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Well, I got the 45-degree mirror out. Kind of a tricky process. First, you remove the side panels from the box:



After removing four nuts, you can draw out the entire tailpiece assembly (including CRT) from the rear:



Use care when sliding out this heavy assembly. Judging by some little nicks around the hole edges in the 45-degree mirror, this CRT was replaced in the past.

The spherical mirror must come out first, to make enough elbow room to withdraw the 45-degree mirror:



You must unscrew the 45-degree mirror clamps from the slanted rails, and then remove the clamps from the mirror. Then with some cautious jiggling and sliding, you can slip the mirror out the side of the box:



The reflective surface looks pretty bad, so off it goes for resilvering:



The spherical mirror looks much. much better, so I may try to use it as-is.

Phil Nelson
Phil's Old Radios
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  #29  
Old 06-30-2017, 02:51 PM
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Is there a way to test my 3NP4 CRT? My Sencore CR70 manual doesn't list settings for it.

The CRT is obviously good enough to make some sort of picture, but it's hard to judge its performance by looking at that tiny CRT face, and I can't view the full image at all, while the mirror is off for recoating.

The turnaround time for recoating is something like 30 days, so I'll try to make progress in other areas in the meantime. I hope to be able to address the horizontal issues by viewing scope forms and peeking in at the CRT face.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html
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  #30  
Old 07-27-2017, 09:43 PM
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The recoated mirror is back from Spectrum Coatings, and it looks good.



We're about to leave on a short vacation, but next week I should be able to install it and give the 609 another trial.

Fingers crossed,

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

Last edited by Phil Nelson; 08-02-2017 at 03:31 PM.
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