Forums :: NEW! Web Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Sep Sun 27, 2020 8:14 pm


All times are UTC [ DST ]





Post New Topic Post Reply  [ 16 posts ] 
Author Message
 Post subject: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Jul Wed 19, 2017 11:06 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
OK so this was one of those Craigslist Finds, and I Really don't have room for this but at 35.00 bucks and the bad cataract interested me.
so I contacted the Seller and then the price jumped because others offered more ( what happened to buying on craigslist at posted prices? )
I made my offer and they said ok, so Took the Drive to Milwaukee, and had to meet the person at a Arby's which was Busy.
the person helped load from their truck into mine, and Came home with it, this was last week.

This is a RCA CTC-11D Set with a bad Cataract.

I found inside the Cabinet the manual, a Nice Tweeking tool, Tubes in Boxes, and a whole lot of White Dust Buildup.

the chassis is Mint, no Burned boards, but it must sat a Very long time as is.

I used my variac and slowly bought it up, no HV but some Audio
I tested the CRT and it about Buried the Test, I then Removed the Chassis and Tested some Tubes and found the 6CG7 H-OSC-Control Tube had intermit leak and Emission.
and 3 Bad Capacitors on the 2 Sweep boards, this all gave me a start to see what the overall condition is.

I power back up but no H Freq lock, Remove the chassis again and found the H-Phase Detector Diodes completely shorted, Replaced those and a couple more Really Weird tested tubes
and got a Decent image. and was happy :)

so Next before I go any Deeper is to do a Cataract Surgery, which is why I wanted the Set to Experiment on

The Serial number on the picture Tube Matches the Serial number on the Back of the Set.

Wish me luck as I am about to Remove the CRT now and Do this :)
I do not have anyone else helping to Take pics but will take pics as I do this, and I am doing this NOW. LOL

The Tube is in my 18" Glass Recycle Bin, So I figure if it implodes then the glass is already in the Bin
I didn't leave it in the Sun, but am using a heat gun, mild heat, and poked away at the edges to find a place to grab and insert some spacers
and it came apart after a bit of heat

7/20/2017
This whole process took only bout 45 mins, it went Very Well, and all is clean
I just have to install the faceplate back on and tape it, then install it back into the cabinet,.
then install the chassis and see how overall the picture looks then make my list up of Capacitors and slowly rebuild the chassis farther.

I was more afraid of removing the CRT from the cabinet than working on this while it was in my Recycle bin.
and I will be more afraid re-installing it, you have to drop the tube in at an angle sort of.

this has been an interesting Experience ! and it was not that bad !


Attachments:
ctc11dsm.jpg
ctc11dsm.jpg [ 73.52 KiB | Viewed 6511 times ]
rcacyc11dsm2.jpg
rcacyc11dsm2.jpg [ 78.97 KiB | Viewed 6511 times ]
rcactc11dsm4.jpg
rcactc11dsm4.jpg [ 55.15 KiB | Viewed 6511 times ]
rcactc11d5sm.jpg
rcactc11d5sm.jpg [ 52.36 KiB | Viewed 6511 times ]
rcactcrt2sm.jpg
rcactcrt2sm.jpg [ 67.46 KiB | Viewed 6503 times ]
faceremoved1.jpg
faceremoved1.jpg [ 71.54 KiB | Viewed 6439 times ]
smfacegunk2.jpg
smfacegunk2.jpg [ 77.54 KiB | Viewed 6439 times ]
faceplate4sm.jpg
faceplate4sm.jpg [ 71.14 KiB | Viewed 6439 times ]
smfaceclean3.jpg
smfaceclean3.jpg [ 54.4 KiB | Viewed 6439 times ]


Last edited by wiseguy on Aug Tue 29, 2017 11:06 pm, edited 2 times in total.
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Thu 20, 2017 3:55 pm 
Member

Joined: Aug Mon 16, 2010 6:58 pm
Posts: 224
Location: Madison, WI
Wow, nice work Terry! I've never attempted a cataract removal, and I admire your courage for diving right in.

I have a CTC-11 with a weak but usable 21FB, so no cataract. Apparently, RCA switched to the 21FJ in later production runs.

Good luck reinstalling the CRT.

-Clark


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Thu 20, 2017 11:40 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
Clark, K9OA wrote:
Wow, nice work Terry! I've never attempted a cataract removal, and I admire your courage for diving right in.

I have a CTC-11 with a weak but usable 21FB, so no cataract. Apparently, RCA switched to the 21FJ in later production runs.

Good luck reinstalling the CRT.

-Clark

I think the hard part so far was trying to figure out the correct Double sided tape thickness

I had looked so close to make sure the protective Glass does not touch the Center.
and to make sure that I could see the Phosphor dots around the Edge, too far the Dots are Blurry, but good in center
too Close and the Center touches the Face of the Tube, which is not good..
for sure there are optical properties in the lens and the PVA, but it was yellowed and Dull.
this protective lens is strange, you would have to see how in person.

so I think I am set !
this is Trial and Error so we will see once I install it back in the Cabinet.
this side of town we had so many bad storms last night that kept me up, so I'll be in bed early and install this tomorrow I hope


Attachments:
CRTReadysm.jpg
CRTReadysm.jpg [ 66.35 KiB | Viewed 6374 times ]
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Fri 21, 2017 2:05 am 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 5363
Location: Woodinville, WA USA
Nice job of removing that cataract. I have never needed to try that procedure, knock on wood.

You already have pretty good looking color bars for an unrestored roundie. I have restored three CTC-11s, and each of them made a surprisingly good picture before restoration. You can find those CTC-11 articles here, if you're curious what I did:

https://antiqueradio.org/televisions.htm

Hope your project goes smoothly!

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


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Fri 21, 2017 3:21 pm 
Member
User avatar

Joined: Nov Thu 11, 2010 6:03 pm
Posts: 1389
Location: Pewaukee, WI
You're lucky the cataract was that far advanced. When RCA style (moldy white) cataracts are just 1-3" into the viewing area that is when it gets tricky....It takes a lot of finesse on the wedges to make progress prying it up, but not crack the safety glass (which devolves the process in to chipping the glass off with a hammer and chisel).

The only RCA style cataracts that have ended well (intact safety glass and CRT) for me either were so bad the glass fell off before I started, or only had a small island of good glue in the center. I'm rather leery about the heat gun method...I've heard a lot more horror stories of spontaneous implosion with collector present with those. I tend to just pick a sunny day and let the sun warm it evenly.

The funnest and safest cataracts to fix are the Zenith style (green halo) cataracts. Those don't require heat (I've done them outside in the dark on 50 degree fall nights), or prying. All you need to do for the green halo is remove the side tape on the CRT, put handles on each end of a steel guitar string, and pull the string through the soft glue, cutting it. Technique is to (start at a corner if rectangular type CRT) start holding both ends and get the cut started and switch to one end (alternate which) when resistance increases. Change angle of wire pull to change cutting speed/resistance. Cleanup of the glue varies from easy to annoying...Newer tubes especially post 1970 tend to have large areas of stubborn glue in the center that even after removing the glass from the CRT face want to stay adhered to the surfaces.....It is kinda like removing caulk from glass at that point


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Fri 21, 2017 8:51 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
Electronic Memory wrote:
You're lucky the cataract was that far advanced. When RCA style (moldy white) cataracts are just 1-3" into the viewing area that is when it gets tricky....It takes a lot of finesse on the wedges to make progress prying it up, but not crack the safety glass (which devolves the process in to chipping the glass off with a hammer and chisel).

The only RCA style cataracts that have ended well (intact safety glass and CRT) for me either were so bad the glass fell off before I started, or only had a small island of good glue in the center. I'm rather leery about the heat gun method...I've heard a lot more horror stories of spontaneous implosion with collector present with those. I tend to just pick a sunny day and let the sun warm it evenly.

The funnest and safest cataracts to fix are the Zenith style (green halo) cataracts. Those don't require heat (I've done them outside in the dark on 50 degree fall nights), or prying. All you need to do for the green halo is remove the side tape on the CRT, put handles on each end of a steel guitar string, and pull the string through the soft glue, cutting it. Technique is to (start at a corner if rectangular type CRT) start holding both ends and get the cut started and switch to one end (alternate which) when resistance increases. Change angle of wire pull to change cutting speed/resistance. Cleanup of the glue varies from easy to annoying...Newer tubes especially post 1970 tend to have large areas of stubborn glue in the center that even after removing the glass from the CRT face want to stay adhered to the surfaces.....It is kinda like removing caulk from glass at that point


I was very Careful on Heatgun settings and never had heat in an any area for a long time, I have seen and heard about the implosions from heat, I am Extra Careful.

Anyways it turned out Excellent, I can now order my Caps and Realign the chassis, tuner needs cleaning for sure, but that all will come in the next few weeks

:)

Terry


Attachments:
smcatdone.jpg
smcatdone.jpg [ 43.35 KiB | Viewed 6290 times ]
smbars.jpg
smbars.jpg [ 49.23 KiB | Viewed 6290 times ]
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Mon 31, 2017 7:06 am 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 10975
Location: Omak,wa,usa
Hello Terry,
well done


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Jul Mon 31, 2017 8:40 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
radiorich wrote:
Hello Terry,
well done


The next Step with this set is Replacing Capacitors, and checking Tubes again, I found 2 6EW6 had shorts, 1 of them had bad leakage.

the Set worked well as it was but I did notice some Ringing in the Video response and audio was touchy to fine tune but sounded fine.
I didnt go into deep Test with the Tubes earlier as I thought i had found all the Weak/ shorted ones.
I have 4 tube Testers, a B&K 707 for fast test, and a Hickok 539B late model, and a Triplett 3444. and a TV-7/B
I hate Dialing in tubes for test so I used the 707 for fast tests, it works well and does catch those bad ones, I didnt pull every single tube till Recently
because i didnt see problems in the area related to the Tubes. now I found them all.

so now I am prepping the chassis and all for Sweep alignments in detail, since I found a tweeking tool inside the cabinet, i suspect someone was tweek happy :)
Even pulled out the VTVM and checked it's Calibration and operation.
There is one odd step that calls for unmodulated 43.8mhz, i had not seen that on other sets, this is for the first Video i.F

I never attempted video/if Sweep on the Reallly olders sets I had like the CT-100 or the 21CT55, I was afraid and they worked well enough to leave as is.

I'll take my time on all this, the cabinet is way Downstairs, so I hope to do this one time and correctly


Attachments:
smctc11dprep2.jpg
smctc11dprep2.jpg [ 119.37 KiB | Viewed 5996 times ]
smctc11dprep.jpg
smctc11dprep.jpg [ 99.63 KiB | Viewed 5996 times ]


Last edited by wiseguy on Aug Thu 31, 2017 12:17 am, edited 1 time in total.
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Catarct Fun
PostPosted: Aug Mon 28, 2017 10:17 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
I am now just getting around to I.F sweep alignments on this set, I have been so Busy with work and I placed my TV7/B tube tester project ahead :)

I wish I had taken a pic of how the sweep looked before hand, it was only a "CONEHEAD" LOL with markers all over, this must be why I found a tweeker tool and manual
inside Cabinet.

I spent about 35 mins to get it as it is so far, I can't understand why it worked so well before, but with Ringing in Video.
you have to use all 3 bias supplies from the B&K 415, but actually its not so bad at all to do alignment , the Tuner plate loading Coil Really has an Effect on Response and Tilt.
and ALSO found the 3rd Video i.f tube shield has intermit contact with the Fingers around it, moving this shield made really adverse Response in the Sweep, I had thought it was
a bad tube Socket, but no, its the Actual shield, not rusty at all, but just poor contact, I'll lightly sand it tomorrow and remove the oxidation

signal is going to a loose spare Tube shield onto Tuner.
I had made all Bias connections on the I.F board then placed the shield over connections then only placed a few screws on the upper part of shield.

I had labeled the Coils to match manual ahead of time to make it easier to find the proper coils.

yes I have the marker levels turned up for pictures, and some get blanked out from camera timing.
Fun project so far.
I will not know how it actually looks in cabinet hooked up till I get the Cabinet up 2 floors or I drag the chassis down.
hopefully in the next 2 weeks


Attachments:
rsz_20170828_pt1.jpg
rsz_20170828_pt1.jpg [ 138.67 KiB | Viewed 5629 times ]
rsz_20170828_154041_pt1.jpg
rsz_20170828_154041_pt1.jpg [ 108.48 KiB | Viewed 5627 times ]
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Aug Wed 30, 2017 4:17 pm 
Member

Joined: Aug Mon 16, 2010 6:58 pm
Posts: 224
Location: Madison, WI
Looking good, Terry. You already had a nice picture before the alignment, so it will be interesting to see what you get now.

I wonder if I should check the shield on the 3rd video IF tube in my CTC-11 :?:


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Aug Wed 30, 2017 11:41 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
Clark, K9OA wrote:
Looking good, Terry. You already had a nice picture before the alignment, so it will be interesting to see what you get now.

I wonder if I should check the shield on the 3rd video IF tube in my CTC-11 :?:


Hello Clark

if you zoom in on some of the Photos you can see some Ringing in Video, and it is /was in the Video, Chroma is fine
look close at the Blue marker, you will see, turn Color Down and it was Still there. or was hehe

and another reason for this was because there was a tuning tool stuck inside :o
there is always room for improvement here, who knows what was tweeked

we will see once I drag the chassis back downstairs sometime in the next few days
I'll post pictures soon, I figure since I have all the Equipment to do this then give it a try for improvement

Terry


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Aug Thu 31, 2017 10:06 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
So I dug more into my Video I.F alignment and what I thought was a tube Shield making poor contact was not the Case at all

I could get a perfect Response then just wiggle anything coil or tube on the video IF board and the response would change BAD.

so I removed the Bottom Shield, which looks like it was never removed, had to use a Soldering Gun and what did I find?? hehe

ALL of the ground connections had rings from bad solder connections and you could actually pull the board away.
hard to see in pictures but I tried to Circle in Red.
Time to Resolder Everything
Fun Fun
Terry


Attachments:
rsz_1ctc11vidifbd.jpg
rsz_1ctc11vidifbd.jpg [ 119.11 KiB | Viewed 5442 times ]
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Sep Fri 01, 2017 7:09 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
More Drama to add to this, I had resolderd the whole board and reconnected everything up with shields in place things were going Excellent till I went to adjust L4 (A2) and the Coil form just crumbled and the slug and all fell out, I swear I barely touched it.
the rest of the coil form was brittle to touch.
so I dug out a similar Coil, which was the form was exactly same size and Glued it (gorilla Glue) to the Base of the coil like the broken one was.

this will have to work till I find a new one, has anyone ever attempted this type of repair?
more pics below, and of video Response after the repaired coil back in
I have the marker levels turned up to try and Take a decent pic but no matter what my Samsung 8+ cell/camera just does not like to take images from the Scope


Attachments:
rsz_vidrespnc2coil.jpg
rsz_vidrespnc2coil.jpg [ 82.78 KiB | Viewed 5398 times ]
rsz_videorespn.jpg
rsz_videorespn.jpg [ 84.96 KiB | Viewed 5398 times ]
Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Sep Sat 02, 2017 2:43 am 
Member
User avatar

Joined: Mar Sun 01, 2009 10:27 pm
Posts: 5326
Location: Ann Arbor, MI
wiseguy wrote:
till I went to adjust L4 (A2) and the Coil form just crumbled and the slug and all fell out, I swear I barely touched it.
the rest of the coil form was brittle to touch.
so I dug out a similar Coil, which was the form was exactly same size and Glued it (gorilla Glue) to the Base of the coil like the broken one was.

What does A2 adjust? Did you change the winding on the substitute form to match how the winding was on the original form? If so it might just work if the core is of similar magnetic material.

From your scope trace it looks like you were able to align the IF strip correctly.

_________________
Tom


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Sep Sat 02, 2017 11:57 am 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
Tom Schulz wrote:
wiseguy wrote:
till I went to adjust L4 (A2) and the Coil form just crumbled and the slug and all fell out, I swear I barely touched it.
the rest of the coil form was brittle to touch.
so I dug out a similar Coil, which was the form was exactly same size and Glued it (gorilla Glue) to the Base of the coil like the broken one was.

What does A2 adjust? Did you change the winding on the substitute form to match how the winding was on the original form? If so it might just work if the core is of similar magnetic material.

From your scope trace it looks like you were able to align the IF strip correctly.


Tom
I used the same windings and tried not to disturb them when I glued the Coil form inside the 2 windings to the old base that the leads went thru, the form I found was the same size, I used the old slug.
the one in my hand above is the Coil after I glued and it Dried, I am still looking for a new one though.
what I do not know is if the type of glue I used will change its shape once things are warm and cold-Hot cycles, I am power cycling it a few times with everything hookup to watch this.

A2 adjust the 42.17 response, A3 adjusts the 45.75 picture, A1 adjust the Tilt and both markers are suppose to be 50%-50% to Valley, which they are and they track perfect when adjusting AGC Bias on the 415 from 6V to 4 Volts


Top
 Profile  
 
 Post subject: Re: RCA CTC-11D Cataract Fun & Alignment
PostPosted: Sep Sun 03, 2017 8:05 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 270
Location: Madison, wisconsin 53718
Excellent Color picture, no convergence or Setup done yet, all I did was slide the chassis in and adjust contrast and color level
there is still a bit to do, but no more intermit Video issues.

also I had an unusual problem after the First power up, which was just about a minute, I unplugged the set to turn the set around.
after I did this I powered back up and I got a dim/ blurry picture about 1/3 the size and noticed the Damper tube was Red plating a little.
so I Fast Removed power and checked both the H output and Damper tubes both still were Excellent, and Flyback Cool to touch.
powered back up again and it Came up with full HV and Size.
I checked for crimped wires and all , all is fine
Nothing loose or intermit
so not sure if this chassis has a problem yet from years ago or what, I had suspected the Lin coil, not sure yet.
so far its been playing Great


Attachments:
rsz_ctcpic.jpg
rsz_ctcpic.jpg [ 96.52 KiB | Viewed 5283 times ]
rsz_ctccolor.jpg
rsz_ctccolor.jpg [ 84.83 KiB | Viewed 5280 times ]
Top
 Profile  
 
Post New Topic Post Reply  [ 16 posts ]  Moderators: Mr. Detrola, 7jp4-guy

All times are UTC [ DST ]


Who is online

Users browsing this forum: Tim Tress and 12 guests



Search for:
Jump to:  


































-->


Privacy Policy :: Powered by phpBB