View Full Version : 25SP22 vs. 25VERP22 and damper tubes
N9ZQA 08-16-2006, 10:24 PM Hi all -
Question - I've got a 1967 Admiral with a 25SP22 CRT. Still looks like it has some life left in it, but has cataracts beginning about 2-3" from the edge. I've done some reading on cataract repair, but the thought of popping the safety glass off the front of an evacuated glass bomb doesn't sit too well with me just yet :no: .
I have a late 70's Zenith with a 25VERP22 tube that works well. Any chance of these two CRTs being even remotely compatible? If possible, I'd like to swap tubes to get the Admiral running and on its way to being a watcher.
Another question - the damper tube in this set is a 6CG3. The set was working well until yesterday - I heard some arcing during startup and looked at the tube. The inside looked like a miniature lightning storm, arcing for about a half second every minute or two. I removed the tube, inverted it, and tapped it a couple times. I saw some particles floating around in the tube.
After I tapped the tube, I put it back in the set and the set ran flawlessly for about a day. So - is the lightning a symptom or a result? I plan on getting another damper tube but want to make sure that there isn't anything else that should get looked at before popping it back in.
Thanks!
Jim
nasadowsk 08-16-2006, 10:32 PM I've had horz outputs that did that too. Generally, when they started arcing, they were done for. AFAIK, it's just something that happens.
N9ZQA 08-17-2006, 10:27 AM Doh - I should have seen the V in the second part number. I've been searching the web trying to find CRT information and I know that has come up a couple different times.
nasadowsk - Hopefully I will have a new damper by sometime next week and will be able to see if this was just a fluke.
Thanks guys!
Jim
Carmine 08-17-2006, 03:32 PM Jim,
I don't know where you're at, but I've got a semi-working color Admiral of similar age. Free if you want it, in the Detroit area.
N9ZQA 08-18-2006, 12:07 PM Carmine -
Thanks for the offer - unfortunately I don't have room for another complete set.
Another question - how hard is it really to remove cataracts from a rectangular tube? This one isn't too bad yet; the cataracts begin at the edge and continue in about 2-3". The center of the tube is unaffected, maybe a bit hazy.
I thought about removing the tube and placing it neck-down in a sturdy 55-gallon plastic garbage can with a couple bags of cat litter or something in the bottom for stability. That part doesn't worry me too much; it's the heating and popping of the safety glass that's got me leery. I don't want to crack the face of the tube.
Anybody have any suggestions or tips/tricks to make this safer? Do you use something like leather aprons and gloves? Outdoors or indoors? Most of the instructions I've seen have been for round tubes, which I would imagine would be slightly stronger due to their construction.
Thanks for the input!
Jim
N9ZQA 08-18-2006, 01:58 PM Andy -
Thanks for the information. Another quick question about your setup though. You mention "the glass should fall off" and "cover the bell with a heavy blanket". Is the face of the tube horizontal or vertical during this process? My thought (from a couple posts ago) was to put the tube in something like a garbage can, with the face pointing up toward the ceiling.
This information has made me a little more comfortable in attempting to revive this tube - thanks again for all the help, guys!
Jim
wa2ise 08-18-2006, 02:56 PM Be sure to wear eye protection like industrial grade goggles. You don't want flying glass getting into your eyes...
wiseguy 08-18-2006, 04:51 PM and drinks lots of beer while you do it..LOL
wiseguy
N9ZQA 08-19-2006, 01:41 AM Andy -
Thanks for the clarification. This isn't seeming as daunting as it did a couple days ago. Plus, I have another set to practice on - a 1965 Admiral with a 23EGP22. Tube is nice and bright but the safety glass has come unbonded almost all the way to the middle, leaving about a 4" circle.
Based on the advice you guys have given me, that one looks a little easier, and since I got it running today, I've got a little more incentive to repair its CRT.
Thanks again to everyone who's responded - it's amazing to be able to toss a question out there and have half a dozen or so people come back with information.
Jim
compucat 08-19-2006, 09:19 AM Andy -
Thanks again to everyone who's responded - it's amazing to be able to toss a question out there and have half a dozen or so people come back with information.
Jim
That's why I read this forum almost every day. I'm sure I'll have more than a few questions when I dig into my Zenith roundie :yes:
bgadow 08-19-2006, 10:53 PM I have done it face up in a trash can-the only drawback I can think of is that any junk particles that might be floating around inside could fall down into the gun and cause problems. The chances of that being a problem are slim, I think.
The next time I get one I'm going to put it facedown in a bathtub full of water for several days. CRTs left outside for a length of time will have the bonding material broken down naturally but I don't know how long it takes for the breakdown to occur.
N9ZQA 08-21-2006, 10:54 AM Wow! :banana:
Got to it this weekend. Figured I'd try on one of the two Admirals that I recently picked up. This one had only about a 4" diameter circle in the center that was visible; everything else was grossly out of focus if visible at all. Even though the tube was a 23EGP22, the spot in the center looked good enough that I thought it would be worth saving.
Placed the tube in a trash can with a 30# bag of cat litter at the bottom for weight, heated the entire face slightly, then began attacking the cataract edge with the heat gun. To my surprise, it loosened up in a few seconds and literally popped free as others had suggested. I was surprised that the tube face was quite cool to the touch even after the process - I was worried about applying too much heat to the face and cracking it.
After cleaning the tube, I used 4 cardboard spacers at the edge to give me about 1/16" clearance and glued the glass back on around the edges. Let it dry, taped it up, and put it back in the set.
Picture looks great - will post before and after shots as soon as I get the pictures out of my camera.
The bathtub idea looks interesting - possibly safer than this procedure, but I don't have any bathtubs on the first floor and would hate to have to explain to my wife why a CRT was enjoying a bubble bath in the tub. :sigh:
Thanks again for all the help, guys. I was incredibly nervous even attempting something like this, but with everyone's detailed instructions and encouragement, it went quite easily. I may even tackle the tube in my other Admiral once I get it back up and running.
Jim
N9ZQA 09-04-2006, 11:38 PM Hi all -
Finally got the pictures out of my camera for the sets I've mentioned in this thread.
First is the 1967 Admiral that started it all. It's currently sidelined with the arcing damper tube mentioned earlier; have a new one on order and hope to get back to it soon.
Second picture is of the 1965 Admiral with the 23EGP22. The cataract on this tube was a lot worse than the first one, so I figured this would be a good one to tackle first.
Third picture - 1965 after checkout, soft-start, and general cleaning.
Finally, 1965 in its final spot, after cataract removal, purity, convergence and CRT adjustment.
Thanks again to all who gave me information on getting this set this far along.
Stay tuned - 1967 Admiral next up for cataract surgery!
Jim
Bobby Brady 09-05-2006, 11:40 AM Those are great sets. They must be very rare. Is either a remote?
bgadow 09-05-2006, 12:07 PM Super job! I really like Admirals from this era but they just don't show up anymore. I think if one did show up I would have to make space for it.
N9ZQA 09-05-2006, 12:46 PM Thanks for the compliments! These sets have probably been the easiest repairwise, but the most difficult as far as cataract removal and color CRT setup. It's definitely been a learning experience and hopefully I'll be able to keep these two running for quite some time.
Bobby -
Neither is a remote, although I do have the service manual for the 1967 and it appears that power tuning was an option on certain chassis/cabinet setups. The tuner/control assembly in the '65 is shown in the service manual, so I would think it would have been an option then as well.
Bryan -
Didn't know that Admirals were that rare; they (at least B/W) seem to be pretty common here in the Midwest. How do/did they stack up against say, a RCA or Zenith from the same era?
Jim
jstout66 09-05-2006, 01:27 PM Jim, where you at in the midwest? I'm in Omaha.
N9ZQA 09-05-2006, 02:17 PM I'm in Joliet, IL.
Jim
bgadow 09-05-2006, 03:25 PM At one time Admirals were plentiful around here. 15-20 years ago I was finding them quite commonly. They were right up there with RCA/Zenith/GE as far as the most common to show up in the secondhand market. They had quite a few dealers back in the day. But all of those sets seemed to have dissappeard in recent years. I cannot recall the last time I saw a sixties Admiral color set anywhere locally.
Some folks, like my uncle (who owned a late sixties console until the early 80s) swore by Admiral. I know they ran into trouble when they started making their own picture tubes (I'm pretty sure the crt in your older set was made by someone else, maybe Video Products? Not sure about the other one.) And the stuff of theirs that I've seen from the seventies seemed third rate. But in the sixties they were at the top of their game & a major player.
Tony V 09-05-2006, 03:31 PM Hi Jim,
I like your sets and it looks true to form watching Emergency on your finished project! I always like the flip down controls on the Admirals and the ones i had were pretty reliable except for the horizontal output tubes. Like Bryan says their not to common on the east coast but have shown up on rare occasions. Just think how many of these early bonded sets were disguarded because of the cataract problem. I know now that if i ever run across another one with cataracts or halo that i can now cure it. I prefer the anti glare glass to the non bonded sets that came out later. Glad you shared your project with us and am looking forward to when you get the other one ready to show.
Tony
N9ZQA 09-05-2006, 09:54 PM Bryan -
Thanks for the information. I haven't been into TVs all that long; I started with radios about 15 years ago and through college and a bunch of moves, never built up much of a collection. But with a house of my own (and a very understanding wife), I've managed to pick up a few sets here and there. Most of what I see around here in Goodwill, antique stores, and Ebay has been Zenith, Admiral, and RCA. I grew up with Zenith and Admiral as a kid - Dad was a TV repairman for a while, so we had a lot of tube sets kicking around. As with anything else - if I only had a couple of those sets now...!
Tony -
Yes, had to watch Emergency once the set was running. Grew up with the reruns as a kid and was thrilled to find it was available on DVD. Fortunately, we have a local channel in the Chicago area that plays many of the older shows (Green Acres, Mary Tyler Moore, Carol Burnett, etc.). For some reason the color on these older sets seems to suit the old programs better.
Jim
blue_lateral 09-05-2006, 10:14 PM Nice Admirals! :thmbsp:
John
ARC Tech-109 09-09-2006, 01:56 PM I have peeled the frosted faceplate off 3 tubes so far using a Burnz-O-Matic torch and alot of patience. The bonding material is the same that is used to laminate automotive windshields and becomes fluid at 350 degrees F, it delaminates around 200 degrees and has insulating properties with respect to heat meaning the tube face itself won't get very hot.
I just heat the entire faceplate up slowly going in a circular pattern to even out expansion and after a while the the faceplate will break loose around the corners, just keep going in this manner for a while and eventually it will fall off. Do position the tube horizontally and support the neck and bell with cat litter bags or something soft and do use a heavy blanket over the bell just for safety. I wear my welding aprons that are leather and also wear my welding helmet with clear faceplates, Im a bit paranoid. Also don't forget to carefully slit the clear tape around the perimeter that covers the bonding resin, I got tricked once from the tape.
So far done 22JP22, 25XP22 and 20 something 22 in a zenith metal.
109
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