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-   -   1964 Zenith Chinese provincial roundie photos! (http://www.videokarma.org/showthread.php?t=169671)

drh4683 06-15-2008 09:46 PM

1964 Zenith Chinese provincial roundie photos!
 
I have finally completed restoration to this set. I waited on putting up photos until the job was complete. This is the set that I found off craigslist a couple weeks ago.
Its a model 6075 and as I mentioned in the previous thread, I cannot find any reference to this model at all, so it must be a very rare, limited production set and zenith just decided to ignore putting this model in their service manuals. Its clear as day stamped on the back "model 6075" and 25LC20QS chassis.
The set did need some work to bring it up to good working order. First off, cateracts was bad. It really upset me as I had to pull the set apart from its original wiring and wire ties to get the CRT out. The chassis was never pulled on this set in its entire history. So I made a video of all details so I could reassemble it exactly the way it looked before. I got kind of overboard on this, as all screws and wire clips had to go back in their exact positions.

Cataracts went perfectly using the heatgun method. Reassembled with the 3m double sided foam tape and sealed the glass with clear tape to prevent dust accumulation.

This set had all of its original tubes which I think is unheard of for a color set of this age. I did unforunately have to replace about 4 tubes, due to grid emission and poor life test. This set had only 5 black caps. 3 under the chassis and 2 on the convergence board. They all got replaced for reassurance. When I recapped the 29JC20 last year, I had to replace a number of mylars which are normally good. So for performance sake, I tested all the mylar caps in this set. Of the 12 or so under the chassis, only 3 were leaky and got replace with sprague orange drops (the only replacement cap to use in zeniths!). only two lytics had ESR off the charts, so they got replaced. The space command chassis worked, but there was a delay in action on the channel up function after I pressed the remote button. Thats a sign of drifted alignment, so I aligned the whole space command chassis. I detail cleaned the chassis and put it all back together while watching my video. After sucessfully reassembing the set, i was excited to turn it on and see the results. Sure enough, a problem was discovered that I didnt pay any attention to when I first got the set. the vertical size was way too low. Size an lin controls did nothing, nor did subbing tubes. So I flip the set on its side to check some voltages to see what the hell was wrong. (I was pretty po'd as I spent a long time making everything perfect when reassembling the set). When I first got the set, the vertical was short but I didnt really pay much attention to it as its typical and normally a simple fix. Not this time. I found out that the B boost to the vertical size control was too low. Sure enough, I can't get at the parts as the cabinet covers it. So guess what, the chassis had to come out again! After some troubleshooting, there was a leaky .01uf disk cap in the B boost circuit to ground in the vertical size control. It simply turned into a 5k resistor lowing the boost to the vertical circuit. Ok, thats good now. Reassemble the set all over again making the wires look as they did before. Now the dial lamp is burnt out, so the tuner now had to get pulled! You can't get at the dial lamp unless you pull the whole thing out and with space command there are more wires to deal with. Put in a new 239 and turned the set back on. guess what, the 239 blew out in about 5 seconds! Noooo!!!!!!! All over again, pull the tuner, another new 239. Now all is well!!
Convergence was very difficult. the lateral magnet assy was defective and had to put a new one on the set. That made convergence much easier and the blue would now move laterally!

All is well with this set now, it works great. Very pleasing picture and a really neat cabinet too. its the HI-FI chassis, so the sound is fenomenal. I really like the volume stepper status lamps next to the VHF tuner. Never seen anything like it before. Im curious if this was done on any other year/model. The space command chassis is custom too as there is a special plug on it for the 3 dial lamps that are controlled by the stepper relay. This one is a keeper.

btw, I made a video of the cateract repair. I'll post that on youtube soon should anyone be curious what its like to do a cateract repair on a CRT. Also to note, this is the original "Zenith" CRT from 1963 which is actually made by RCA with the zenith name on it (eia#274).

jpdylon 06-15-2008 09:48 PM

Fantastic job Doug!

One of my dream sets is an early zenith remote set. Can't wait to see the cataract surgery video. :yes:

Sandy G 06-15-2008 09:51 PM

Ooooooh, Dat's Purdy..!! (grin)

Snade 06-15-2008 09:55 PM

Wow. That is nice.

Great find and restore.

Mark (aka Snade)

old_tv_nut 06-15-2008 10:16 PM

You done good!

radiotvnut 06-15-2008 10:48 PM

Very pretty TV! You did a GREAT job on it!

ChrisW6ATV 06-15-2008 10:52 PM

That is a great set and a nice restoration.

ceebee23 06-15-2008 11:21 PM

OH! WOW ...just plain WOW! What a tremendous looking set!! Great job!!

Tony V 06-16-2008 01:12 AM

Man thats nice! I think this is the best restoration you've done yet Doug! I was going to ask you about the cataract concidering this type was found on RCA tubes, but saw that you explained it in this update. Have you found many of these rebranded Zenith color tubes in other Zenith tv's you've run across in the past? I'm glad to see such a unique tv being kept in good hands. Fantastic job!
-Tony

JB5pro 06-16-2008 08:20 AM

That set is as good as it gets!
 
I used that 3M tape also. I put one layer around the outermost edge of the tube and one layer on the outermost edge of the safetyglass to keep it from showing in the frame. The edge of one layer hit an angle surface of the other layer to give an expected proper distance between the glass and tube face.
The process you did is how anything I do goes.
Nice to know you did the right thing to make it exactly original.
That must be one of the greatest roundies on the planet!

veg-o-matic 06-16-2008 08:44 AM

I just had a roundiegasm.

Need cigarette.

veg

kbmuri 06-16-2008 09:53 AM

:guitar:

Frkn awesome. :ntwrthy:

andy 06-16-2008 10:07 AM

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Celt 06-16-2008 10:08 AM

Gorgeous set! :yes:

Dan Starnes 06-16-2008 10:08 AM

Extremely nice and for sure a keeper.
Dan


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