I just picked up tonight a RCA 721TS for $95. I was a little hesitant on that price, but it seems they go for that or more on ebay. I didn't take a tube tester, but I checked the heater pins on the CRT and got good continuity while I was there.

It belonged to a lady that recently passed away and her son sold it. It was in the family since new. They said they stopped using it in 1959. It looks like most of the tubes are non-RCA replacements except the CRT. I hope it tests well.

One question: Is the tuner supposed to have detents and clunk for each of the channels?

Yes, it should clunk. If it has all the knobs and the cabinet and insides are in good condition, I think you did fine at $95.

On my 630 the little ball bearing that allows it to "clunk" fell out. I think whatever spring mechanism it sits in broke. I suspect it's a fairly common problem; it won't keep the tuner from working.

$95 is a deal IMO, the broken detent seems to be a common problem on these, I had one once like that, the spring breaks and the ball falls out. The good thing is you only need channel three so you can set it and forget it.

A good deal for a one-family set with a stand. This article describes how I restored my 721TCS (same TV in a console cabinet):

http://antiqueradio.org/RCA721TCSTelevision.htm

The article has a link to the service manual. These are great performers when restored right.

Enjoy!

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

Thanks for the info guys!

I can feel the knob turning something inside, but I didn't think it was supposed to be a variable tuner.

All the knobs are there and original. So is the number plate. Decals look great. The finish is crazed, but that can be fixed. A few dings, but nothing major. It will really look sharp when restored.

In fact, there's so little wear around the knobs they either used gloves to turn it on all the time, or they had it plugged into a switched outlet. I remember some people used to do that and left the tv switch on all the time so they didn't have to adjust the volume every time. And, St. Louis only had one VHF station for much of this set's working life, so no need to change channels.

Here's a link to the RCA factory service manual on this set (very similar and the same info as Riders, just a little clearer): https://archive.org/details/Rca721tsTelevisionServiceData

Nope. RCA didn't use variable tuners. The detent is likely broken. That stand doesn't look original, but, still a great deal.
On my 10" radio tv RCA the detent wasn't broken. It was actually made too shallow to hold the bearing..I put a later one in with a bearing. It clicks again...
The model of my set is 8TR29.
Bill Cahill