This person thinks this RCA is a Zenith:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2170239179&category=3638

and this one thinks this RCA is a Motorola:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2170217798&category=3638

despite the fact the both say RCA Victor right on them!