So with the covid lockdown keeping me in the basement I've been going after partially done early color projects....
Where to begin on this? Shortly after my last post Benman offered to trade his CBS 205 for my 21CT55... looking carefully I came to the conclusion that I'd be trading for the same chassis in a bigger less attractive cabinet with a smaller CRT and I'd be trading a set that needed an alignment and refinish for an unrestored chassis that might also need an alignment and decided to fix my 21CT55 (which has been working and looking excellent for a year and a half now and I should post that saga eventually).....one interesting thing on the 21CT55 was it didn't need an alignment...All it needed was the off tolerance IF resistors changed and the channel osc slugs retuned.
That led to me to pull nearly all the decent 6AN8s out of the CT-100 to replace all the weak shorted specimens in my 21CT55....the CT-100 sat dark since then with the tubes missing (and eventually a bag of swapmeet 6AN8s sitting on top)....
Late last week another slug cracked on my Moto 21CT2B so while I wait on another chroma bandpass coil from eBay for it I bounced over to the CT-100. After getting a fresh crop of 6AN8s in it replacing the 6DE6 somebody placed in the 2ND IF with the correct 6DC6, changing off tolerance resistors in the 2ND and 3RD IF, and changing the paper cap in the tone circuit the hack that recaped it left I was easily able to get it to pass decent chroma through the IF... there's some chroma/sound crosstalk in the lumina channel I need to fix yet (If resistor replacement in the IF I've since done hasn't fixed it) but it is now watchable.
I'm almost done going through the IF resistors. I also plan to replace the 1-2 remaining original leaking coils in it and the other peaking coils with the same ones I used in my 21CT55 (the ones miniman82 recommends from digikey). Whoever put in the somewhat random assortment of peaking coils in this set also did a lot of sloppy J-hooks (sometimes a J to another J to finally the cap lead) sloppy soldering and other baloney that makes me question their competence to select correct peaking coils. I plan to go through and change all off tolerance resistors in the color and video stages as well as the HV and to change the doorknob capacitors out before they can fail...
If progress holds I'll have this set done soon.