What, if anything, do the last two letters (or a letter and a number) signify in the chassis numbers of RCA/Thomson TVs? I'll use the chassis number of my own set as an example: CTC185A7.

Was the CTC185xx chassis used in RCA/Thomson TVs with 23, 25, 27-inch CRTs as well as the 19" table model? For that matter, how many (if any) RCA consoles used this chassis, or was it not powerful enough to drive anything larger than a 19-inch CRT? :scratch2:

Thanks in advance.

I don't know about the ctc-185 specifically, but many of these characters denote a set with the same base chassis but more added features. For example, remote control or stereo sound.

I've seen the 185 chassis used in 19" and 25" and I think a 27". I've seen the newer CTC203 chassis used in 19" on up to 36" sets. The CTC175's were used in 19"/20" sets, the 176 in 19"/20" sets with A/V jacks, and the 177 in 25" up to 36" sets. Some chassis will be mono, some will be stereo, some will have PIP, etc.

What gets me is that the CTC-169 was used in all sets from 20" ProScan up to 65" projection. They just added "PTV", and a convergence subchassis to the number for the projection version. It was truly the same CTC-169! And not a bad chassis either. I hated the 170, but the 169s were pretty reliable and easy to troubleshoot.

Charles