Found this old RCA at the thrift store
 

So for some reason the local Salvation Army, which has never had a set made before the BPC era before, has this RCA ColorTrak set for the princely sum of 10 dollars. Looking at the label on the back it seems to be from 1978, which would make it the oldest set I own if I get it.

https://i.imgur.com/CBd8Fg3.jpg

https://i.imgur.com/zmwGbNH.jpg

My main questions are...is it worth 10 dollars, for one, and also how does the channel changing work with only one knob? Any other info about this set would be appreciated as well.

If it is a deltagun CRT set and the CRT is good then you've got $100 of CRT with a $10 price tag...If it is inline then it is worth $10 if you want it enough to spend $10 on it.

The tuner is a varactor tuner. A varactor diode is a diode the capacitance of which varies with the voltage across it. BPC sets use digital logic to drive the varactor, early varactor sets use a bunch of resistors to set the voltage for each channel and a big tuning knob shaped switch to select the right resistors...The resistors are variable to provide fine tuning for each channel...Some sets let you set each the resistor for each knob position for any channel (UHF or VHF) you desire to skip blank chanels and or make motorized UHF/VHF remote tuning easier.

I personally try to never buy any all solid state set unless it is a deltagun color that I can keep as a CRT donor, a first inline (like a GE portacolor or an early 70's sony), or something extremely special. There are so many American made vacuum tube and tube/SS hybrid sets out there that even those I can't save all that I find.

It's not a half bad looking set. Maybe a little on the plain side. $10 is hardly a sum worth crying about if it turns out to be a dud. Besides, you can always talk to the manager and be like, "you know you're going to throw that out in a week, what's the best you can do on it?"

It should work if you plug it in, or well, you know, attempt to work. Will they let you?

If I go back tomorrow with someone to help me load it I'm gonna shimmy it across the floor to the outlet to plug it in before I pay. I just couldn't move the thing by myself.

This is the oldest set I've found that was intact (I found the sad remains of a 60s Admiral TV/hi-fi combo once) so that makes it worth something to me.

Those convert really well to video input with a 2 transistor circuit if your tuner is unusable. I'm assuming it has a power transformer.

if that has the fold down chassis with a delta gun crt,you got the deal of the day.those were built like tanks and that heavy crt will take a jolt or two and restore nicely.good score

I tested it out at the store and it worked! Brightness was a little low but the picture came right up with a good raster (I hope I used that term right, I've been trying to learn old TVs from shango66 on YouTube). Just need to find a twin lead to coax adapter and a video source so I can check the picture properly.

What is the chassis (CTC) number?

Unfortunately I'm not gonna have a chance to take the back off today so I don't know yet.

I noticed that on the back it has two separate sets of RGB pots, one labeled "Picture" and the other labeled "Driver". Is that a common thing sets had before the 1980s?

Well, let's see, for a sawbuck ("that's $10 to you city slickers" as a local TV ad used to say) you could:
1) buy a fast food dinner that will give you bad indigestion
2) buy a ticket to a really lousy movie
3) buy this TV, which will teach you a lot, looks kinda neat, and you could keep for years. You could sell it for 2 or 3 times what you paid with a little patience, maybe more, and you sure couldn't do that with #1 or #2!

He just knows he wants it! AAHH..snag it anyways, there's good parts if nothing else. If it plays, all the better!

Oh I did snag it, but it's been sitting away from home for a few months now. I haven't really had time to fiddle with it.