This may seem like a strange request. I have a Zenith color roundie set that is currently in storage such that I can't easily access the back of the cabinet. I believe it to be early 60s vintage, it's a basic cabinet with a flat top and sides, and legs. I have the chance to get some TV tubes for next to nothing, and I would like to identify what chassis is in the Zenith (or just narrow it down to a few possibilities) so I can save just the tubes I would likely use. I did my best to read the model number, and all I can make out is "S72". Mine it the type that uses a rotary VHF and UHF controls that are staggered, if that helps. Any ideas on what chassis I have would be greatly appreciated!

Pictures would help greatly.

Deleted. I missed where he said it was a roundie.

You mentioned the controls are staggered. Are they arranged like the controls in this video? If so, you probably have the 24MC32 chassis.

https://www.youtube.com/watch?v=Mo8n3jLoM_U

Thanks Tim, you nailed it. I have a different cabinet with no speaker on the left but the same controls and the same RGB volume knob. Thanks again.

So Zenith was still making roundie's in 1966 ..well obviously. I would thought rectangular tubes were normal by then.

Actually, Zenith was still making roundies in 1967.

Actually, Zenith was still making roundies in 1967.

The last model "roundy Zenith" was my favorite model.
The chassis was similar to their first rectangular model.
It seems like all the big manufacturers, still made them that model year. Usually as their entry-level models. :yes:

Zenith control layouts and appearances were somewhat common through the years with some exceptions. The last Zenith roundie with the 24NC32 chassis was unique. As for the staggered channel knobs, could be anything from an optional UHF model to the late production 24MC32/42.

A model and/or chassis number is really needed here.

Thanks everyone for the help, Marty I know I really need to pull the set out of storage to know for sure, but I'm going to assume a 24MC32 or 24MC42 for the time being. My goal is to grab any vacuum tubes that might be useful as spares while I have access to them, if I have the wrong chassis number it's not the end of the world!

That said, does anyone have a list of the tubes used in either of these chassis? I checked my service manuals over the weekend and I don't have the right ones, and I wasn't able to find anything online.